RESEARCH ARTICLE
How much research shared on Facebook happens
outside of public pages and groups? A comparison
of public and private online activity
around PLOS ONE papers
开放访问
杂志
Asura Enkhbayar1
, Stefanie Haustein1,2,3
, Germana Barata4
, and Juan Pablo Alperin1,5
1Scholarly Communications Lab, Simon Fraser University, Vancouver (加拿大)
2School of Information Studies, 渥太华大学, Ottawa (加拿大)
3Centre Interuniversitaire de Recherche sur la Science et des Technologies (CIRST),
Université du Québec à Montréal, 蒙特利尔 (加拿大)
4Laboratory of Advanced Studies in Journalism, State University of Campinas (巴西)
5School of Publishing, Simon Fraser University, Vancouver (加拿大)
关键词: altmetrics, Facebook, public engagement, science communication
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
抽象的
Despite its undisputed position as the biggest social media platform, Facebook has never
entered the main stage of altmetrics research. In this study, we argue that the lack of attention
by altmetrics researchers is due, 部分地, to the challenges in collecting Facebook data
regarding activity that takes place outside of public pages and groups. We present a new
method of collecting aggregate counts of shares, reactions, and comments across the
platform—including users’ personal timelines—and use it to gather data for all articles
发表于 2015 到 2017 in the journal PLOS ONE. We compare the gathered
data with altmetrics collected and aggregated by Altmetric. The results show that 58.7% 的
papers shared on Facebook happen outside of public spaces and that, when collecting all
shares, the volume of activity approximates patterns of engagement previously only observed
for Twitter. Both results suggest that the role and impact of Facebook as a medium for
science and scholarly communication has been underestimated. 此外, 他们
emphasize the importance of openness and transparency around the collection and
aggregation of altmetrics.
1.
介绍
As of October 1, 2019, Facebook reports 2.49 billion monthly active users (Facebook, 2019):
大约 32.3% of the world’s population (联合国, 2019). The rise of Facebook
has been accompanied by the rapid “platformization” of the web in general (Helmond, 2015),
and academia has been no exception (Chan, 2019). Like more academically oriented sites
(例如, Academia.edu and ResearchGate), Facebook has become an important tool as well as
a subject of research. As the extent of platformization and its impact on society receives in-
creased attention (Zuboff, 2015), several studies have shown that the platform is being used in
an educational context, outside and inside of classrooms (Roblyer, McDaniel, 等人。, 2010;
Selwyn, 2009). The general public uses Facebook mostly for purposes of information sharing
(Baek, Holton, 等人。, 2011). In academia, almost 40% of scientists and engineers use it
引文: Enkhbayar, A。, Haustein, S。,
Barata, G。, & Alperin, J. 磷. (2020). 如何
much research shared on Facebook
happens outside of public pages and
团体? A comparison of public and
private online activity around PLOS
ONE papers. Quantitative Science
学习,1(2), 749–770. https://doi.org/
10.1162/qss_a_00044
DOI:
https://doi.org/10.1162/qss_a_00044
支持信息:
https://www.mitpressjournals.org/doi/
suppl/10.1162/qss_a_00044
已收到: 31 八月 2019
公认: 08 二月 2020
通讯作者:
Juan Pablo Alperin
juan@alperin.ca
处理编辑器:
Ludo Waltman
版权: © 2020 Asura Enkhbayar,
Stefanie Haustein, Germana Barata,
and Juan Pablo Alperin. 已发表
under a Creative Commons Attribution
4.0 国际的 (抄送 4.0) 执照.
麻省理工学院出版社
How much research shared on Facebook happens outside of public pages and groups?
经常, as do 50% of scholars in the social sciences, 艺术, and humanities (McClain, 2017;
Van Noorden, 2014).
同时, the growing importance of social media as a medium for scholarly com-
munication has led to the creation and consolidation of a new field of study known as
altmetrics, which tries to quantify and understand how research circulates online, 包括
on social media platforms (Erdt, Nagarajan, 等人。, 2016). 然而, despite the increasing number of
altmetric studies and Facebook’s social significance and use as a platform for sharing informa-
的, there has been limited research that specifically focuses on the circulation of research on
Facebook (Enkhbayar & Alperin, 2018; 弗里曼, Roy, 等人。, 2019; Ringelhan, Wollersheim, &
Welpe, 2015).
One reason for the lack of research might be that, according to most altmetric studies, 关于-
search does not appear to be shared on Facebook broadly. In their review of nine studies, Erdt
等人. (2016) report that only 7.7% of research articles are shared on Facebook—far less than
这 59.2% found for Mendeley libraries or 24.3% for Twitter. The coverage can vary depend-
ing on discipline—with biomedical and health sciences among the areas with the highest cov-
erage (Costas, Zahedi, & Wouters, 2015; Fenner, 2013)—and country, with studies written by
authors in Brazil being shared most among Latin American journals (Alperin, 2015).
此外, the coverage has been reported to vary by data aggregators. 例如,
Twitter coverage for PLOS ONE publications was reported as 23.9% on Plum Analytics and
57.0% on Altmetric. 相似地, the coverage for Facebook fluctuated between 7.9% on Lagotto
和 16.3% on Plum Analytics (Zahedi & Costas, 2018乙). 全面的, Facebook coverage has
been reported to be significantly lower than that observed for Twitter (Haustein, Costas, &
Larivière, 2015; Xia, Su, 等人。, 2016; Zahedi & Costas, 2018乙), which corroborates findings
that academics prefer Twitter over Facebook for science outreach (Hassan et al., 2017;
McClain, 2017; Thelwall, Haustein, 等人。, 2013).
There is also significant variation depending on the way in which the mentions of research
on Facebook are retrieved and aggregated (Zahedi & Costas, 2018A). Searching for mentions
of research by querying Facebook’s API, which measures the number of times links are shared
anywhere on Facebook, identifies more mentions than when using data mining approaches,
which can only be performed on public Facebook pages. The latter approach is used by
Altmetric, while Plum Analytics makes use of the API. As we argue here, although quite tech-
nical, this methodological distinction has far-reaching implications for the results of commonly
used altmetric indicators and thus the understanding of the role of Facebook in the circulation
of research. Analyzing and comparing retrieval methods is thus a central issue with regard to
the reliability and reproducibility of altmetrics and, as a consequence, for the field of altmetrics
一般来说 (Haustein, 2016).
进一步来说, the limitation of working with public-only pages may omit a significant
portion of the research-related activity that happens on the platform. A recent study shows that
academics on Facebook tend to share science on the platform in a personal and intimate man-
ner, rather than professionally for science outreach and communication (McClain, 2017). 这
would suggest that looking only at public pages, as is done by the majority of altmetric studies,
misses a significant amount of Facebook activity related to scholarly papers. McClain (2017)
also suggest differences in how academics view and use public and private spaces within so-
cial media platforms such as Facebook. 像这样, in this study we seek to measure the extent
and nature of this difference between public and private acts related to scholarly documents
(Haustein, Bowman, & Costas, 2016), with the goal of understanding how much engagement
with research is taking place on Facebook, including both public and private spaces.
Quantitative Science Studies
750
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
2. 背景
2.1. Methods for Collecting Facebook Altmetrics
There are two general approaches used by those seeking to collect metrics related to the cir-
culation of research on Facebook: The first is the extraction of mentions of articles from the text
of posts in a curated list of public groups and pages, presumably through data-mining ap-
proaches. This method is used by Altmetric1. The second is to use Facebook’s API to query
engagement counts, as calculated by Facebook. In contrast to the first approach, the API ap-
proach covers not only counts but activity across all of Facebook, including engagement that
takes place in user’s private pages. PlumX Metrics2 and the method developed for this study
use the API approach.
2.1.1. Extracting mentions from public pages on Facebook
A data-mining approach is able to capture the number of mentions an article receives in posts
on a curated list of public Facebook pages and groups. This approach has been used by
Altmetric since October 2011 (Altmetric, 2019A). To do this successfully, they use a list of
public pages and groups that can then be monitored for posts that contain basic metadata
about the article in question. Although Altmetric declined to provide specific details of their
text processing methods, they do report that they use the “Pages” endpoint of the Facebook’s
Graph API and that they monitor known web domains (IE。, the first part of a URL), 包括
links that have been “shortened” (Altmetric, 2019乙). A review of posts identified by them also
reveals that they additionally monitor some identifiers (例如, DOIs), but although it is theoret-
ically possible, we found no evidence that they monitor additional metadata (例如, title or
author names). 而且, they attempt to identify and combine the mentions of research
outputs with several major identifiers (例如, the DOI, PubMedID, arXiv ID, ADS ID, SSRN
ID, RePEC ID, and ISBN) into a single record. It is not clear in which ways Altmetric iden-
tifies multiple URL variations for the same article (例如, links to other output formats, 例如
PDF), or what pages are included in their curated list.
One of the main strengths of this approach is that the resulting data can be linked to a page
that is publicly available, making such data auditable (例如, it is possible to see the full content
of the Facebook post to verify the existence of the link to the research, as well as the identity of
the person who posted it). The major limitation, 然而, is that it can only be done for posts
that are on public pages, as Facebook does not share—and so Altmetric cannot collect—the
text of posts that are private.
2.1.2. Querying the Graph API for engagement counts
The second approach makes use of Facebook’s Graph API to access engagement counts for
what Facebook calls objects (groups of URLs that Facebook has determined to refer to the
same content) in their social graph (the network of users that make up Facebook’s content).
These engagement counts comprise the number of shares (URLs posted by a user), reactions
(“likes” or other emotion icons), comments (responses to a shared URL), and plugin comments
(comments created by users on an external URL using the Facebook comments plugin).
Facebook’s Graph API accepts a single URL as a parameter, and returns both a Facebook
Object ID, along with the number of times the object has been shared, liked, and commented
1 https://www.altmetric.com/
2 https://plumanalytics.com/learn/about-metrics/
Quantitative Science Studies
751
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
数字 1.
Idealized case for the collection of Facebook metrics for a scientific article using multiple URLs.
on by users across Facebook. This includes posts on users’ timelines (largely restricted from
public view) as well as posts on public pages (visible to anyone)3.
据我们所知, since Lagotto stopped collecting Facebook metrics due to
changes to the Graph API (Fenner, 2014) and PlumX Metrics replaced individual counts for
shares, likes, and comments with the total count of all actions (艾伦, 2016), no altmetric pro-
vider presents Facebook counts across platforms and identifiers using the API method. 那里
是, 然而, plans in place by Our Research (formerly ImpactStory) and Public Knowledge
项目, in collaboration with Crossref, to add Facebook as a data source for Crossref’s Event
数据 (Alperin, Enkhbayar, 等人。, 2018).
One of the main strengths of this approach is that it can access activity around research
articles that happens out of public view (at the expense of allowing that activity to be audited).
A limitation is that the data collected are not auditable, so while it is possible to track a larger
volume of engagement counts, it is not possible to view the underlying posts that led to it
taking place. Another limitation is that due to the reliance on specific URLs for querying, 这
method is particularly sensitive to what URLs are identified for an article. 在之前的工作中, 我们
built on Wass’s (2018) detailed overview of the challenges of working with DOIs and URLs
and subsequently with Facebook’s Graph API (Enkhbayar & Alperin, 2018). In this study, 我们
explore the relation of an external URL to the Facebook internal Open Graph objects and en-
gagement counts, which is foundational to any approach that collects Facebook metrics for
scientific articles using their API. We also show how the API-based approach can be used to
combine the results from multiple URLs that may exist for the same article, as well as those
related to various major identifiers (例如, DOIs and PMIDs). 图中 1 we show an idealized
case of an article with several related URLs and identifiers whose Facebook Object IDs can
then be used to arrive at a single aggregated total engagement count.
3 Although this method collects information about activity that happens outside of public view, it relies solely
on available data that are provided and displayed by Facebook itself. None of the collected data contain any
information that can be used to identify individuals.
Quantitative Science Studies
752
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
2.2. Differences Between Collection Methods
Both approaches are limited to some extent as they rely on knowing all of the URLs and iden-
tifiers that can be used to refer to a given research article. 然而, there are two important
differences between both methods:
1. Type of engagement. The number of “mentions” by means of textual analysis of a post
has a different conceptual meaning than the count of shares, reactions, or comments as
provided by Facebook’s API. 此外, some data providers (例如, Plum X) decide to
aggregate the reported number of shares, likes, and comments to provide a single
Facebook count. 因此, it is important to differentiate between reported Facebook
计数, which could represent one of several things: mentions on public posts, 一
of several reported Facebook metrics (shares, reactions, comments), or the sum of these
指标.
在本文中, we primarily discuss and compare the Facebook shares we retrieved with
our version of the second method with the mentions captured by Altmetric using the
第一的. We are unable to use Plum’s implementation of the API approach because they do
not make data available for research. We also compare both of these to tweets and
retweets on Twitter (as collected by Altmetric), which are considered similar forms of
appraisal acts to posting links on Facebook (Haustein et al., 2016).
2. Scope of engagement. Both approaches cover different scopes of content available on
Facebook. In order to access the full text of Facebook posts, they need to be posted in
public groups and pages that are tracked by the data aggregator. 相比之下, querying
Facebook’s API provides a way to access the counts across all of Facebook’s posts, 在-
cluding user posts on each other’s timelines, those made in private or closed groups,
and posts made in any other group, regardless of whether it has been previously iden-
tified as being relevant.
在本文中, we will refer to mentions collected using the first method—used to ana-
lyze public posts—as public-only shares (销售点) and mentions collected using the second
method—used to analyze posts anywhere on Facebook—as all-engagement. When this
engagement refers specifically to the sharing of a link on Facebook (as opposed to com-
ments or reactions to that link), we refer to it as all-engagement shares (AES).
A summary of the similarities and differences between both approaches can be found in
桌子 1.
2.3. How Do Studies Address These Differences?
Both approaches have been studied to some extent in the existing literature. Studies that com-
pare altmetrics to citations and to each other often rely on data provided by Altmetric (例如,
Costas et al., 2015; Haustein et al., 2015; Thelwall et al., 2013). 相比之下, studies that have
sought to compare several data aggregators are accordingly comparing different collection
methods depending on the choice of data providers (Zahedi & Costas, 2018A; Zahedi,
Fenner, & Costas, 2014).
Stark differences can be observed in the degree and clarity with which the differences be-
tween collection methods for Facebook are addressed. A few publications addressed neither
the type of engagement nor the scope of engagement collected (Peters, Kraker, 等人。, 2015;
Robinson-García, Torres-Salinas, 等人。, 2014; Xia et al., 2016; Zahedi & Costas, 2018A). Half
Quantitative Science Studies
753
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
桌子 1. Comparison of public-only and all-engagement metrics for Facebook
方法 1: Public-only metrics
⊖ Only captures number of mentions
方法 2: All-engagement metrics
⊕ Provides several metrics: number of shares, sum of all reactions,
comments, and comments made outside of Facebook
using Facebook plugins
⊖ Only captures posts on public pages
⊕ Captures any activity across Facebook
⊕ Captures occurrences of any link variant for
an article at known publisher domains
⊕ Captured engagement is auditable (posts with
mentions and their authors can be reviewed)
⊖ Only captures specific URLs that are queried
⊖ Reported engagement numbers are aggregated for all users
and can’t be reviewed or disambiguated
○ Limited by the curation of relevant identifiers and URLs
○ Limited by the curation of relevant identifiers and URLs
○ Data provided by Altmetric API for a publication by
○ Data accessed through Facebook’s Graph API on URL level
using one of several persistent identifiers
(access key required)
(developer key required)
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
of these studies used only a single data provider, while the others compared the data from
several providers.
The vast majority of studies that investigated Facebook as an altmetric source did, 任何一个
implicitly or explicitly, specify the type of engagement represented in their data (例如,
Chamberlain, 2013; Fenner & 林, 2014; Freeman et al., 2019; Hassan et al., 2017; Priem,
Groth, & Taraborelli, 2012; Ringelhan et al., 2015; Thelwall et al., 2013). 然而, the scope
of engagement would still be disregarded in the methods sections.
开始于 2014, several publications have not only clearly addressed the type of engage-
ment but also specified the scope of engagement for collected Facebook metrics (Haustein,
2016; Haustein et al., 2015; Zahedi & Costas, 2018乙; Zahedi et al., 2014; Zahedi, Fenner, &
Costas, 2015).
全面的, the scope of captured engagement seems to be overlooked more frequently than
the type of captured engagement, with the remark that studies comparing several collection
methods were more likely to mention the scope of engagement. With the increasing impor-
tance of Facebook as a social platform used by academics in professional as well as private
settings, revisiting the role and impact of Facebook as a data source for altmetric research
might be required. As part of that undertaking, we suggest paying closer attention to the dif-
ference between POS and AES counts as collected (and compared) by various data
聚合器.
3. METHODOLOGY
To ensure that all articles had the same opportunity to be shared on Facebook, avoiding jour-
nal biases and differences between paywalled and open access articles, while at the same time
maintaining a sufficiently large sample, we analyze all articles published in the journal PLOS
ONE between 2015 和 2017. As a multidisciplinary and open access megajournal, PLOS
ONE has the advantage of publishing a wide variety of fields of research free to read and ac-
cessible by the general public.
Quantitative Science Studies
754
How much research shared on Facebook happens outside of public pages and groups?
Using the rplos package for R (Chamberlain, Boettiger, & Ram, 2018), on July 17, 2018 我们
检索到的 61,872 articles that were published in PLOS ONE from the beginning of 2015 直到
the end of 2017. The precise query used was
searchplos(q=”*:*”,
fl=”id, publication_date, title, 作者”,
fq=list(’publication_date:[2015-01-01T00:00:00Z TO 2017-12-
31T23:59:59Z]’,
’journal_key:PLoSONE’,
’doc_type:full’))
We used the DOIs of these 61,872 documents to query the Altmetric API and retrieved 50,819
responses with at least one mention across all of the sources tracked by Altmetric. Responses
from the Altmetric API include mentions to various versions of the article, including those in
考研, PubMed Central, and arXiv, when available. Of these, 9,632 (19.0%) had at least
one Facebook mention and 43,083 (84.8%) had at least one Twitter mention. These corre-
spond to our POS and Twitter (TW) data sets respectively.
Collecting the AES data was more complex. 第一的, we identified 10 different URL patterns
that users might have used to share the respective article on Facebook (桌子 2). The first two
URLs are based on Crossref’s guidelines for creating links from a DOI. In March 2017, Crossref
changed the recommended DOI link from http://dx.doi.org/{土井} to https://doi.org/{土井}
(Hendricks, 2017). URLs 3 到 8 correspond to various links that can be found on the PLOS
ONE website itself, including the landing page URL, links to various subpages (IE。, authors,
comments, related articles, 指标) and the link to the PDF version of the article. 此外,
for each DOI, we attempted to retrieve the PubMed ID and Pubmed Central ID with the iden-
tifier converter provided by the National Centre for Biotechnology Information (NCBI)4. 仅有的
five articles (two corrections and three announcements by the PLOS staff ) did not return a
Pubmed ID. These articles have corresponding landing page URLs for PubMed and
PubMed Central (URLs 8 和 9) that incorporate the respective IDs if found.
We then used the URL endpoint of the Graph API v2.105 to retrieve the AES counts for each
的 618,720 URLs. We started the data collection script on July 18, 2018 and finished on
七月 23, 2018. 的 618,720 URLs queried, a Facebook Object was found for 69,983
(11.3%) of cases. 然而, due to the way Facebook’s API works, 37,062 的 69,983
URLs (53.0%) were mapped to Facebook Objects with zero shares, reactions, and comments.
These were treated the same as those that were not found in the API.
Each of the remaining Facebook Objects were stored, along with their Object ID. Facebook
attempts to assign the same Object ID to URLs that correspond to the same content, 例如
those that use different protocols (IE。, https vs http), those that redirect to the same page (例如,
links with or without a www at the beginning), or those that have additional characters at the
结尾 (例如, a trailing slash or some URL parameters).
In a previous study (Enkhbayar & Alperin, 2018), we analyzed a random sample of 100,000
articles to investigate the mapping between DOIs, their respective URLs and Facebook
Objects—a challenge that has been described and studied in parts by Wass (2016).
Although the best practices by publishers (such as the proper use of canonical URLs and
4 https://www.ncbi.nlm.nih.gov/pmc/tools/id-converter-api/
5 https://developers.facebook.com/docs/graph-api/reference/v2.10/url
Quantitative Science Studies
755
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
桌子 2. Overview of URL types based on three identifiers (DOI, Pubmed ID, Pubmed Central ID)
1
2
3
4
5
6
7
8
9
10
URL type
土井
doi_old
landing
authors
指标
comments
有关的
pubmed
pmc
图案
https://doi.org/{土井}
http://dx.doi.org/{土井}
http://journals.plos.org/plosone/article?id={土井}
http://journals.plos.org/plosone/article/authors?id={土井}
http://journals.plos.org/plosone/article/metrics?id={土井}
http://journals.plos.org/plosone/article/comments?id={土井}
http://journals.plos.org/plosone/article/related?id={土井}
http://journals.plos.org/plosone/article/file?id={土井}&type=printable
https://ncbi.nlm.nih.gov/pubmed/{pmid}
https://ncbi.nlm.nih.gov/pmc/articles/{pmcid}/
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
metatags) improve the mapping, using a random sample of over 100,000 DOIs and only four
URL variants for each article, we encountered problems in the mapping between URLs and
Facebook Objects in 12% of cases. Using the same methods, we could not unambiguously
map a Facebook Object to an article for 24 (0.04%) articles in our PLOS data set. The reason
for the difference between the degree of discrepancies can be traced to the higher homo-
geneity of this data set. All articles in this study were published within a time frame of
3 years and in the same journal, whereas the previous study analyzed a random sample
的 100,000 articles indexed in the Web of Science, 发表于 2009 和 2015
(Piwowar, Priem, 等人。, 2018). 因此, after removing all problematic articles, the final data
set contains 61,848 文章.
Because of the interdisciplinary nature of PLOS ONE, we used the article-level subject clas-
sifications from Piwowar et al. (2018) to assign each article to a single discipline by assigning it
to its most frequently cited NSF specialty (as indexed by the Web of Science). The NSF clas-
sification system used in Piwowar et al. (2018) comes in three levels of granularity: grand dis-
纪律, 学科, and specialties. In our analysis we focus on the disciplinary level as it
provides a good midpoint between the big picture and detail. 然而, specialty classifica-
tions are used at times when a detailed look seems appropriate and useful, as in the case of
reported correlations.
The disciplines of Arts (two articles) and Humanities (15) are excluded from the analysis
due to the low number of publications. By matching DOIs and titles between the PLOS pub-
lications that we collected and were provided for the disciplinary analysis, we arrived at
57,902 articles with a grand discipline, discipline, and specialty, 尽管 3,929 articles are miss-
ing those. Of these articles without disciplinary information, 3,374 articles were either correc-
系统蒸发散, retractions, or published by the PLOS ONE staff, which are not considered traditional
research outputs and, 最后, were not included in the data provided by Piwowar et al.
(2018). 因此, 仅有的 555 articles are missing disciplinary information for miscellaneous reasons
(例如, errors in the metadata). 这些 3,929 articles without disciplinary information are excluded
from analyses pertaining to disciplines, but not dropped from the overall data set.
Quantitative Science Studies
756
How much research shared on Facebook happens outside of public pages and groups?
桌子 3. Coverage for Twitter (TW), all-engagement shares (AES), and public-only shares (销售点)
2015
2016
2017
AES
8,596 (33.8%)
6,992 (37.2%)
5,827 (33.1%)
All years
21,415 (34.6%)
销售点
3,981 (15.7%)
3,058 (16.3%)
2,584 (14.7%)
9,623 (15.6%)
TW
16,976 (66.8%)
13,807 (73.4%)
12,281 (69.7%)
43,064 (69.6%)
All articles
25,427
18,809
17,612
61,848
The data used to produce the results are available at https://doi.org/10.7910/DVN/3CS5ES
(Enkhbayar et al., 2019) and has been published under a CC0 license. The code to reproduce
all figures and tables is available at https://doi.org/10.5281/zenodo.3381821 (Enkhbayar,
2019) and is published under the MIT license. The code to collect the original data can be
found at https://doi.org/10.5281/zenodo.1314990.
4. 结果
We organize our results in two broader areas: an analysis of coverage for the different collec-
tion methods and an analysis of the volume of engagement found. To address the former, 我们
present the coverage for all metrics (AES, 销售点, TW) followed by a detailed look at the differ-
ence between the two Facebook methods, including a disciplinary breakdown. To address the
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
数字 2. Coverage of articles that received one of the three engagement types (n = 46,286) 为了
推特 (TW), public-only shares (销售点), and all-engagement shares (AES).
Quantitative Science Studies
757
How much research shared on Facebook happens outside of public pages and groups?
桌子 4. Coverage of articles that were only found by all-engagement shares (AES) and public-only shares (销售点) 分别, 此外
articles that were found by both approaches. The number of articles found by either method is displayed in the last column
2015
2016
2017
AES
5,414 (57.6%)
4,540 (59.8%)
3,745 (59.2%)
All years
13,699 (58.7%)
AES and POS
3,182 (33.9%)
2,452 (32.3%)
2,082 (32.9%)
7,716 (33.1%)
销售点
799 (8.5%)
606 (8.0%)
502 (7.9%)
1,907 (8.2%)
Any FB
9,395
7,598
6,329
23,322
后者, we compare the extent of engagement across the three metrics, followed by a detailed
inspection of the Facebook share counts, again including a disciplinary breakdown.
4.1. Comparison of Retrieval Methods
We compare AES retrieved from the Graph API using our method with two metrics collected
from Altmetric: POS on Facebook and the number of TW on Twitter. As discussed, Twitter is
considered to be the most used social media platform for disseminating research, and as such
serves as a useful point of comparison.
4.1.1. Coverage
Comparison of AES, 销售点, and TW Table 3 shows the coverage for AES, 销售点, and TW across all
years for all 61,848 文章. Twitter shows the highest coverage for each year, covering 43,064
(69.6%) 文章. These coverage numbers are followed by the coverage determined by the
Graph API method, totaling 34.6% (21,415) 文章. 最后, Altmetric’s POS displays the
lowest coverage among these three metrics with 15.6% (9,623) articles found for all years.
The proportion of articles covered across individual years remains stable for each method.
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
的 46,286 articles that are covered by at least one of the three methods, 15.7% (7,270)
of the articles are covered by all three data collection methods, while half (49.6%, 22,964) 的
the articles were only shared on Twitter. One quarter (24.3%, 11,226) of publications were
both tweeted and shared on Facebook, but have not been indexed as POS by Altmetric.
全面的, 仅有的 3,222 (7.0%) articles shared on Facebook were not shared on Twitter, but were
caught by one of the two Facebook collection methods. 数字 2 displays the exact counts and
overlaps of each method.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
Facebook coverage in detail Focusing on the Facebook data collection methods shows that the
proportion of articles found with each method remains constant across years (桌子 4). 在
average, of all articles that were shared on Facebook (IE。, found in AES or POS; n = 23,322)
7,716 文章 (33.1%) are shared by both approaches. 13,699 (58.7%) are only found with
the API method, 尽管 1,907 文章 (8.2%) are only found with Altmetric’s approach.
Coverage by discipline Half of all PLOS ONE output is classified as Clinical Medicine (50.7%),
one quarter as Biomedical Research (24.8%), 和 11.7% as Biology (数字 3). 心理学
(2.9%), Engineering and Technology (2.0%), Earth and Space (1.9%), 健康 (1.9%), Social
科学 (1.3%), and Physics (1.1%) follow as most frequent disciplines published in PLOS
ONE. 推特 (TW) consistently shows a higher coverage for every discipline, 范围从
the highest in Psychology, where almost every paper was distributed on Twitter (94.2%,
Quantitative Science Studies
758
How much research shared on Facebook happens outside of public pages and groups?
数字 3. Coverage of disciplines for AES, 销售点, and TW.
1,583), to the lowest in Chemistry (44.4%, 150). Even the lowest Twitter coverage is still higher
than the highest covered discipline for POS (社会科学: 35.0%, 256). AES ranges from the
highest coverage in the Social Sciences (70.5%, 516) to Chemistry (8.0%, 83). The distribution
of disciplines for all articles and for the different collection methods (AES, TW, and POS) 能
be found in Figure 3 and in table form in Appendix A.
Difference between Facebook methods per discipline Combining retrieval methods, 22,928 文章
were shared on Facebook (IE。, found in AES and/or POS). One third of these articles (7,612; 33.2%)
were found by both approaches, 半数以上 (13,464; 58.7%) were only found by the Graph
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
数字 4. Percentage of papers found by both Facebook retrieval methods (public-only shares
(销售点) via Altmetric only and all-engagement shares (AES) via Facebook API only) per NSF disci-
满的. Articles found by both methods and POS only are assumed to reflect public activity and those
found by AES to show private activity.
Quantitative Science Studies
759
How much research shared on Facebook happens outside of public pages and groups?
数字 5. Expected number of articles for observed engagement counts for Twitter (TW), 全部-
engagement shares (AES), and public-only shares (销售点). The method of least squares was used on
binned values to determine the α of each distribution; 那是, we can read an expected value of
大致 0.01 articles with 1,000 shares, which can be understood as 1 在 1,000 articles with a share
count between 891 和 1,122 (the limits for the logarithmic bins are 2.95–3.05).
API method, and Altmetric retrieves 8.1% (1,852) of articles that are not found via the Graph API.
这意味着 41.3% of Facebook activity related to PLOS ONE papers is shared in public
空间, 尽管 58.7% are shared in exchanges that are not captured by POS approaches.
Appendix B provides a full breakdown of the share of articles that were found privately,
publicly, or by both methods across all disciplines.
The ratio of posts on public pages (articles found by both methods vs. only POS) 和所有
posts (articles found by both and only AES) is highest in Earth and Space (55.1%), 其次是
社会科学 (49.6%), 健康 (48.7%), 心理学 (47.9%), and Professional Fields (47.5%)
(数字 4). In these fields, almost half of all Facebook engagement is in public spaces. 上
other end of the spectrum, in Engineering and Technology (24.8%), Physics (28.0%),
Chemistry (32.5%), and Mathematics (35.1%), the great majority of all Facebook activity hap-
pens outside of public pages and groups and is thus also not captured by Altmetric.
Despite missing 58.7% of articles overall, Altmetric’s approach indexes mentions for a sig-
nificant number of articles that are not captured by the Graph API (数字 4). Clinical Medicine
stands out, with the highest number of articles that were only indexed by Altmetric’s method
(11.0%), while Earth and Space (2.6%), 社会科学 (3.0%), and Biology (3.3%) 展示
the lowest shares. 总共, Altmetric found 1,853 (8.1%) articles that couldn’t be indexed by
our method.
4.2. Engagement Counts
Having compared coverage overall and at the discipline level, we inspect the volume of en-
保证 (IE。, 计数) that we retrieved (AES) with Altmetric’s POS and TW.
Quantitative Science Studies
760
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
桌子 5. Descriptive statistics for each distribution, including the α for the fitted power law functions
AES
销售点
TW
Count
21,415
9,623
43,064
最小
1
1
1
AES
销售点
Max
12,473
186
8,626
Median
2
1
3
Geometric mean
2.4
1.5
3.2
桌子 6. Spearman correlation with zero imputed metrics (n = 61,848)
AES
1
销售点
0.48
1
A
2.0
2.5
2.1
TW
0.45
0.36
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
4.2.1. Comparison of AES, 销售点, and TW
We calculated basic descriptive statistics for all three metrics (桌子 5). POS displays less ex-
treme maximum engagement counts, as well as a lower median and geometric mean6 com-
pared to both AES and TW. Although AES reports the highest maximum engagement count in
数据, both the median and the geometric mean show that TW is still, 一般, register-
ing higher engagement counts. In addition to comparing the distributions for each metric, 我们
calculated Spearman correlations between each pair, after replacing missing values with zeros
(桌子 6)7. Correlations were highest between AES and POS (ρ = .48), followed by AES and TW
(ρ = .45) and POS and TW (ρ = .36).
The data underlying all three metrics are highly skewed, an effect observed and described by
various scholars in bibliometrics: See Lotka’s and Price’s laws (Lotka, 1926; Nicholls, 1988), 作为
well as other altmetric studies (艾森巴赫, 2011; Haustein, Peters, 等人。, 2014). 因此,
direct comparison of the arithmetic mean and variance based on the observed data is limited
in its use (纽曼, 2005). 反而, several metrics based on the fitting of power law functions
and required base parameters (IE。, α and xmin) have been proposed. Milojevic´ (2010) built on
Newman’s work to propose a pragmatic approach to estimating the slope α of empirical data
套. Most data sets encountered in research exhibit small sample sizes and considerable noise,
which affects the validity and usefulness of fitting theoretical functions as suggested by
纽曼 (2005). Milojevic´ suggests partial logarithmic binning of observed values, followed
by a simple least squares fit (LSF) of the newly binned values to determine α. 这种方法
provides an intuitive and effective approach to compare several distributions, with the added
benefit of a visual representation of the complete data that is not distorted by the noise in the
long tail.
6 The geometric mean is the calculation of the arithmetic mean based on log-transformed values, 其次是
a reverse log-transformation to the original scale. 因此, this approach is less prone to extreme values in the
data and more appropriate for the given data set.
7 While the reasons for the absence of values varies by collection method (例如, a page not indexed by
Altmetric for POS or a share made without a link for AES), the end result is that, if the method did not find
any shares, it is as if they did not happen. Zero imputation applied to 40, 433 (65.4%) articles for AES,
52,225 (84.4%) for POS, 和 18,784 (30.4%) for TW.
Quantitative Science Studies
761
How much research shared on Facebook happens outside of public pages and groups?
数字 6.
年.
Letter value plot of the absolute difference between AES and POS counts across the
Using Milojevic´’s (2010) recommended parameters, we used a binning threshold (k) 的 5
and a bin size of 0.11. After fitting LSF slopes (数字 6), AES shares display the lowest α = 2.0,
followed by Twitter (α = 2.1), while POS exhibits the highest value (α = 2.5; IE。, the values
taper off quicker for POS in contrast to AES and TW). 此外, the original data (尤其
for Twitter) deviates from the fitted line for lower engagement counts, indicating a hooked
power law distribution, which is another commonly observed and studied property of distri-
butions in the information sciences (纽曼, 2005; Thelwall & Wilson, 2014).
4.2.2.
Facebook counts in detail
Given that the API (AES) and data mining (销售点) methods are both covering the same data
来源, we can also compare differences in counts for the 7,716 articles that had nonzero
数字 7. The ratio of articles with greater, 降低, or equal AES and POS counts per discipline.
Quantitative Science Studies
762
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
counts for both. Of these, 5,223 (67.7%) had more AES than POS, 2,027 (26.3%) articles re-
turned the same number of shares for both methods, 并且只有 644 (6.0%) of all articles re-
turned a higher POS count. 数字 6 shows a letter value plot8 for those articles that
displayed a difference between counts. Plotting the absolute differences on a logarithmic scale
provides a comparison of the medians and several other percentiles. Two observations for ar-
ticles with a higher POS count stand out: (A) 从 2015 到 2017, the number of articles with
higher POS than AES counts reduces from 200 到 95 文章, 和 (乙) while the median differ-
ence remains stable at 2, the number of articles with higher differences drastically reduces (IE。,
the higher percentiles in the plot disappear for POS > AES).
4.2.3.
Facebook counts by discipline
虽然 67.7% of the articles have a higher AES count, we observe large differences by dis-
cipline (数字 7). In Professional Fields, this ratio even goes up to almost 90%. The ratio drops
到 60% for both Clinical Medicine and Biomedical Research—the disciplines with the most
出版物. With the decreasing share of articles with higher AES counts (from around 90%
in Professional Fields down to 60% in Biomedical Research), we observe that the share of
articles with equal AES and POS counts increases—from around 10% in the Social Sciences
到 32.5% in Biomedical Research. 反过来, the number of articles with higher POS counts
never exceeds 7.5% (Clinical Medicine). No articles with higher POS counts were found for
Mathematics or Chemistry.
5. DISCUSSION AND CONCLUSION
This study compared two data collection methods for retrieving Facebook activity for scientific
journal articles. Based on PLOS ONE articles published between 2015 和 2017, we analyzed
the variations in coverage and extent of the difference in Facebook engagement counts of pub-
lic Facebook posts retrieved by Altmetric via data mining techniques (销售点) with all Facebook
engagement counts retrieved via the URL-based Facebook Graph API (AES). 在这样做, 我们
found differences in the volume and disciplinary distribution of Facebook engagements cap-
tured by both approaches, which serves to highlight that each differs in the type and scope of
engagement they collect. 像这样, our study serves to highlight the importance of considering
which approach is most appropriate in any given context.
The lack of strong correlation between counts found between both methods (桌子 6), 这
different slopes in how engagements of each are distributed (数字 5), and large disciplinary
差异 (数字 7) all show that the activities captured by each method are distinct. 甚至
though POS is largely a subset of AES, the counts derived from each method should be con-
sidered distinct indicators. 因此, the use and application of either metric should con-
sider how the type and scope of engagement measured by each method relates to the
phenomenon of interests. 例如, some might argue that the POS method is more appro-
priate for capturing science communication activities, while the AES method might be more
appropriate for understanding individuals’ sharing practices. In this study, we remain agnostic
about what each metric is best suited for and instead focus on describing how they differ.
8 The letter value plot extends the classic box plot to provide more detail for big, heavy-tailed data sets. 每个
bound of a box represents a percentile of the data set. The lowest box resembles a traditional box plot with a
solid line for the median and the bounds at 1 − ¼ (75% below the boundaries of the box). Each box then
continues to indicate the 1 − ⅛ (87.5%) bounds, 1 - 1/16 (93.75%) bounds, and so on until a border con-
dition is met. Outliers are finally those data points that lie outside of the final plotted box. See Hofmann,
Wickham, and Kafadar (2017) for more details about the graph.
Quantitative Science Studies
763
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
We should note that our study benefited from the use of a particularly homogenous data set
from PLOS ONE. The fact that all articles were published on a single website facilitated the
identification of relevant URLs to be queried in the Facebook Graph API and allowed us to be
more precise in our data collection and comparisons than would otherwise have been possi-
布莱. Studies seeking to use the AES approach across publishers may need to consider using
different URL variants for each publisher website and for the multiple places in which articles
may appear (例如, if they are republished by an aggregator). This limitation may also hold true
for the POS approach, but it is particularly evident in the AES approach. This said, efforts are
under way to implement the AES approach on a large scale (Alperin et al., 2018). 而且,
our code is available for others to experiment (Enkhbayar, 2019).
Our analysis shows that, at least under these idealized conditions, more than half of all
Facebook engagement takes place between users and therefore is not counted by the POS
方法. This shows that working with public-only pages captures only a subset of the re-
search-related activity that happens on the platform. The large share of activity in users’ time-
lines seems to corroborate findings by McClain (2017), who shows that academics on
Facebook tend to share science on the platform in a personal and intimate manner, 而不是
professionally for science outreach and communication.
Although AES coverage values for PLOS ONE papers are still only half those of Twitter
(34.6% 与. 69.6%), they are also twice as high as was found with POS (15.6%), and roughly
double what was previously reported for PLOS ONE publications (Zahedi & Costas, 2018乙).
This suggests that the importance of Facebook as a data source for researchers interested in
science communication and public engagement on social media may have been underesti-
mated by altmetrics researchers. The proportion of articles covered across individual years re-
mains stable for each method, even as the number of social media users still increases annually,
albeit more slowly on Twitter (Facebook, 2019; 推特, 2019). This might indicate saturation of
the Facebook and Twitter communities with regard to sharing scientific research articles.
Coverage varied widely by discipline for each metric. 然而, disciplines were usually
ranked similarly for each metric in terms of coverage, indicating that disciplinary differences
applied to all data sources. Almost all Psychology articles were tweeted (94.2%), 尽管
Chemistry had the lowest Twitter coverage (44.4%). This lower value is still higher than the
highest POS coverage (Social Sciences at 35.0%), but lower than the highest AES coverage
(Social Sciences at 70.5%).
To better understand the differences between AES and POS methods we compared articles
that were indexed by only one of the two approaches with each other. One third of articles
were found by both methods, 尽管 58.7% were only retrieved by AES. Likely due to an ad-
vantage of the POS approach, which finds references to a wider range of URLs across scholarly
域, Altmetric is able to retrieve 8.2% additional articles with Facebook activity, 哪个
were not discovered the URL-based AES approach.
更重要的是, the difference in coverage between the POS and AES methods varies
across disciplines, putting the so-called hard sciences (IE。, Engineering and Technology,
Chemistry, Physics, Mathematics) at a greater disadvantage when measured by public posts.
For these disciplines, AES found three to four times the number of articles that POS did. 甚至
in disciplines where the advantage was lower (例如, 社会科学, 健康, 心理学, 和
Professional Fields) the AES approach still produced twice as many results. This proportionally
lower ranking of the hard sciences by Altmetric’s implementation of the POS approach has im-
portant implications for all altmetrics studies using their data. 例如, Haustein et al. (2015)
report the lowest Facebook coverages for these fields, but would likely have yielded different
Quantitative Science Studies
764
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
results if using the AES method. Part of this lower coverage may thus not be due to lower engage-
ment overall but rather to the nature of that engagement. At the other end of the spectrum,
although still much lower than articles discovered by AES only, the share of documents discov-
ered only by POS is particularly high in Clinical Medicine. These articles might be missed by
AES because they are being shared with a different URL (known to Altmetric but not included in
这 10 variations used by us). 全面的, this once again underlines the importance of paying
more attention to the scope of engagement in altmetric studies involving Facebook data.
We also showed that different retrieval techniques vary in the number of Facebook shares
they uncover for each article. As is to be expected and shown previously for other citation and
social media-based indicators, the distributions of Facebook and Twitter activity per document
are skewed (纽曼, 2005). 此外, as Thelwall and Wilson (2014) report for citations,
the results indicate hooked power-law distributions, especially clearly for Twitter. It is further
interesting to note that Facebook counts that include both public and private engagements
resemble public Facebook counts only moderately (ρ = .48), at the same level as they resem-
ble tweets (ρ = .45), while correlations between POS and TW are lower (ρ = .36). The analysis
of power-law distributions and correlations suggests that public and private engagement on
Facebook related to scholarly articles are not identical. 此外, Facebook engagement
that includes private spaces seems to more closely resemble tweeting behavior than public
engagement on Facebook does. 因此, the collection of public engagement data should not
be used to predict private engagement counts.
Among the 7,715 PLOS ONE papers retrieved by both methods, engagement counts were
identical for 26.3% of articles. AES counts exceeded POS in 67.7% of the cases, while POS
reported higher counts than AES 6.0% 当时的. Over the three years analyzed, the share as
well as the extent to which POS counts exceed AES counts continuously decreased. 上
disciplinary level, results vary dramatically across fields. In the Professional Fields, AES counts
exceeded POS for almost 90% of the articles, which demonstrates a particularly strong ten-
dency by users to share scientific articles in private spaces. On the other end of the spectrum,
Clinical Medicine and Biomedical Research had a larger share of public Facebook engage-
蒙特, even if more than half of all publications’ engagement still took place outside of public
pages and groups. The proportion of articles with equal POS and AES counts also varies, 和
disciplines that have a higher number of matches tending to have a lower proportion of articles
with higher AES counts drops. 那是, at the discipline level, AES counts are either higher than
POS counts, or they are equal. 因此, the number of articles with higher POS counts never
surpasses 7.5% (the proportion reached by Clinical Medicine).
Our study shows that the retrieval method has a significant effect on results and commonly
used altmetrics. Findings demonstrate that the reliability and reproducibility of Facebook data in
the context of altmetrics are questionable (Haustein, 2016). These differences have far-reaching
implications for our understanding of the role that Facebook plays in the diffusion of and en-
gagement with scholarly articles, by highlighting the significantly higher levels of engagement
that take place outside of public spaces on the platform. We therefore urge all altmetric data
aggregators and authors of altmetric studies to carefully consider the type and scope of engage-
ment that is relevant and to be transparent and open about the shortcomings of respective
retrieval methods.
NOTE ON RESEARCH ETHICS
This study is part of a larger project and is registered at the Office of Research Ethics of Simon
Fraser University with the Study Number 2016s0170. Despite reporting on data about
Quantitative Science Studies
765
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
.
/
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
engagements that happen outside of public view, this study relies entirely on publicly avail-
able aggregate data. It did not, as the methods describe, do any data collection requiring the
use of private tokens for access. That is to say, the data themselves are not actually “private”—
what is private are the posts in which some of the sharing took place and the data contain no
information that might be used to identify individual subjects. 更, the analysis is
primarily about the nature of links to scientific articles shared on Facebook, and as such does
not qualify as human subject research. This was the understanding of the Office of Research
Ethics at Simon Fraser University where we registered our study and is supported both by com-
monly used definitions of human subject research, such as that provided by the NIH9, 和
more specific web research ethics frameworks (Bowser & Tsai, 2015).
致谢
We would like to thank and acknowledge Altmetric for access to the Facebook (销售点) 和
Twitter data, as well as for comments, feedback, and clarifications on an earlier version of this
manuscript. We also acknowledge the Observatoire des Sciences et des Technologies (OST)
CIRST for access to their in-house database, including the Web of Science and our data.
最后, we would like to thank Joe Wass (Crossref ) and Scott Chamberlain (rOpenSci) for de-
tailed technical conversations and writings on the URLs, DOIs, and APIs. Our development of
the AES approach would not have been possible without their work.
作者贡献
Asura Enkhbayar: 概念化, 数据管理, 形式分析, 调查,
方法, 软件, 可视化, Writing—original draft, Writing—review & 编辑.
Stefanie Haustein: 形式分析, 资金获取, 调查, Writing—review &
编辑. Germana Barata: 概念化, 调查, Writing—review & 编辑. Juan
Pablo Alperin: 概念化, 形式分析, 资金获取, 调查,
方法, 项目管理, 监督, Writing—original draft, Writing—review
& 编辑.
COMPETING INTERESTS
JPA is Associate Director of the Public Knowledge Project (PKP) and is working with AE to
develop a service that collects Facebook metrics for journals using PKP’s Open Journal
系统.
资金信息
This study was supported by the Social Sciences and Humanities Research Council of Canada
through Grant (892-2017-2019) to JPA and SH. The funders had no role in study design, 数据
collection and analysis, decision to publish, or preparation of the manuscript.
DATA AVAILABILITY
The data used to produce the results is available at https://doi.org/10.7910/DVN/3CS5ES
(Enkhbayar et al., 2019) and has been published under a CC0 license. The code to reproduce
all figures and tables is available at https://doi.org/10.5281/zenodo.3381821 (Enkhbayar,
2019) and is published under the MIT license. The code to collect the original data can be
found at https://doi.org/10.5281/zenodo.1314990.
9 https://grants.nih.gov/policy/ humansubjects/research.htm
Quantitative Science Studies
766
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
参考
艾伦, 磷. (2016). PlumX’s Facebook Altmetrics—Measure Up! Plum
Analytics. Retrieved June 3, 2019, 来自 https://plumanalytics.
com/plumx-facebook-altmetrics-measure-up/
Alperin, J. 磷. (2015). Geographic variation in social media metrics:
An analysis of Latin American journal articles. Aslib Journal of
Information Management, 67(3), 289–304. https://doi.org/10/
gf356b
Alperin, J. P。, Enkhbayar, A。, Piwowar, H。, Priem, J。, & Wass, J.
(2018). Collecting, Calculating and Displaying Altmetrics with
Open Source. Retrieved from http://summit.sfu.ca/item/18390
Altmetric. (2019A). Embiggen [Ruby]. Retrieved fromhttps://github.
com/altmetric/embiggen (原创作品已发表 2015) .
Altmetric. (2019乙). When did Altmetric start tracking attention to
each attention source? Retrieved June 5, 2019, from Altmetric.
com website: https://help.altmetric.com/support/solutions/arti-
cles/6000136884-when-did-altmetric-start-tracking-attention-to-
each-attention-source
Baek, K., Holton, A。, Harp, D ., & Yaschur, C. (2011). The links that
bind: Uncovering novel motivations for linking on Facebook.
Computers in Human Behavior, 27(6), 2243–2248. https://土井.
org/10/b4j2ts
Bowser, A。, & Tsai, J. 是. (2015, 可能). Supporting ethical web re-
搜索: A new research ethics review. 在诉讼程序中
24th International Conference on World Wide Web (PP.
151–161). https://doi.org/10/dpct
Chamberlain, S. (2013). Consuming article-level metrics:
Observations and lessons. Information Standards Quarterly, 25
(2), 4. https://doi.org/10/gc3jvm
Chamberlain, S。, Boettiger, C。, & Ram, K. (2018). rplos: Interface to
the Search API for “PLoS” Journals. Retrieved from https://CRAN.
R-project.org/package=rplos
Chan, L. (2019). Platform Capitalism and the Governance of Knowledge
Infrastructure. https://doi.org/10.5281/zenodo.2656601
Costas, R。, Zahedi, Z。, & Wouters, 磷. (2015). Do “altmetrics” cor-
relate with citations? Extensive comparison of altmetric indica-
tors with citations from a multidisciplinary perspective. 杂志
of the Association for Information Science and Technology, 66
(10), 2003–2019. https://doi.org/10/gfs4m5
Enkhbayar, A. (2019). ScholCommLab/fhe-plos: Preprint release.
https://doi.org/10.5281/zenodo.3381821
Enkhbayar, A。, & Alperin, J. 磷. (2018). Challenges of capturing en-
gagement on Facebook for Altmetrics. STI 2018 会议
会议记录, 1460–1469. Retrieved from http://arxiv.org/abs/
1809.01194
Enkhbayar, A。, Haustein, S。, & Alperin, J. 磷. (2019). Data for: 如何
much research shared on Facebook is hidden from public view?
https://doi.org/10.7910/DVN/3CS5ES
Erdt, M。, Nagarajan, A。, Sin, S.-C. J。, & Theng, Y.-L. (2016).
Altmetrics: An analysis of the state-of-the-art in measuring re-
search impact on social media. Scientometrics, 109(2),
1117–1166. https://doi.org/10/f884k9
艾森巴赫, G. (2011). Can tweets predict citations? Metrics of so-
cial impact based on Twitter and correlation with traditional met-
rics of scientific impact. Journal of Medical Internet Research, 13
(4). https://doi.org/10.2196/jmir.2012
Facebook. (2019). Number of monthly active Facebook users
worldwide as of. Retrieved from [图形]. In Statista website:
https://www.statista.com/statistics/264810/number-of-monthly-
active-facebook-users-worldwide/
Fenner, 中号. (2013). What can article-level metrics do for you? PLOS
生物学, 11(10), e1001687. https://doi.org/10/gf3hrc
Fenner, 中号. (2014). Facebook. Retrieved June 5, 2019, 从
Lagotto Documentation website: http://www.lagotto.io/docs/
facebook/
Fenner, M。, & 林, J. (2014). The Mystery of the Missing ALM.
Retrieved June 3, 2019, from Lagotto website: http://www.lagot-
to.io/blog/2014/03/07/the-mystery-of-the-missing-alm/
弗里曼, C。, Roy, 中号. K., Fattoruso, M。, & Alhoori, H. (2019).
Shared feelings: Understanding Facebook reactions to scholarly
文章. ArXiv:1905.10975 [Cs, Stat]. Retrieved from http://arxiv.
org/abs/1905.10975
Hassan, S.-U., Imran, M。, Gillani, U。, Aljohani, 氮. R。, Bowman, 时间.
D ., & Didegah, F. (2017). Measuring social media activity of sci-
entific literature: An exhaustive comparison of scopus and novel
altmetrics big data. Scientometrics, 113(2), 1037–1057. https://
doi.org/10/gcgjht
Haustein, S. (2016). Grand challenges in altmetrics: Heterogeneity,
data quality and dependencies. Scientometrics, 108(1), 413–423.
https://doi.org/10/gfc5cp
Haustein, S。, Bowman, 时间. D ., & Costas, 右. (2016). Interpreting
‘Altmetrics’: Viewing Acts on Social Media through the Lens of
Citation and Social Theories. 在C中. 右. Sugimoto (埃德。), Theories of
Informetrics and Scholarly Communication. https://doi.org/
10.1515/9783110308464-022
Haustein, S。, Costas, R。, & Larivière, V. (2015). Characterizing so-
cial media metrics of scholarly papers: The effect of document
properties and collaboration patterns. PLOS ONE, 10(3),
e0120495. https://doi.org/10/gf26fd
Haustein, S。, Peters, 我。, Sugimoto, C. R。, Thelwall, M。, & Larivière,
V. (2014). Tweeting biomedicine: An analysis of tweets and cita-
tions in the biomedical literature. Journal of the Association for
Information Science and Technology, 65, 656–669. https://土井.
org/10/q6f
Helmond, A. (2015). The platformization of the web: Making web
data platform ready. Social Media + 社会, 1(2),
2056305115603080. https://doi.org/10/gfc8p4
Hendricks, G. (2017). Crossref DOI display [网站]. Retrieved
可能 6, 2019, from Crossref website: https://www.crossref.org/
display-guidelines/
Hofmann, H。, Wickham, H。, & Kafadar, K. (2017). Letter-value
plots: Boxplots for large data. Journal of Computational and
Graphical Statistics, 26(3), 469–477. https://doi.org/10/gf38v7
Lotka, A. J. (1926). The frequency distribution of scientific produc-
活力. Journal of the Washington Academy of Sciences, 16(12),
317–323.
McClain, C. 右. (2017). Practices and promises of Facebook for sci-
ence outreach: Becoming a “Nerd of Trust.” PLOS Biology, 15(6),
e2002020. https://doi.org/10/gbjzmd
Milojevic´, S. (2010). Power law distributions in information sci-
恩斯: Making the case for logarithmic binning. Journal of the
American Society for Information Science and Technology, 61
(12), 2417–2425. https://doi.org/10/bm7ck6
纽曼, 中号. 乙. J. (2005). Power laws, Pareto distributions and
Zipf’s law. Contemporary Physics, 46(5), 323–351. https://土井.
org/10/c6x8tx
Nicholls, 磷. 时间. (1988). Price’s square root law: Empirical validity
Information Processing &
and relation to Lotka’s law.
管理, 24(4), 469–477. https://doi.org/10/cx7s84
Peters, 我。, Kraker, P。, Lex, E., Gumpenberger, C。, & Gorraiz, J.
(2015). Research data explored: Citations versus altmetrics.
ArXiv:1501.03342 [Cs]. Retrieved from http://arxiv.org/abs/
1501.03342
Quantitative Science Studies
767
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
How much research shared on Facebook happens outside of public pages and groups?
Piwowar, H。, Priem, J。, Larivière, 五、, Alperin, J. P。, 马蒂亚斯, L。,
Norlander, B., … Haustein, S. (2018). The state of OA: A large-
scale analysis of the prevalence and impact of Open Access ar-
ticles. 同行杂志, 6, e4375. https://doi.org/10/ckh5
Priem, J。, Groth, P。, & Taraborelli, D. (2012). The Altmetrics
收藏. PLOS ONE, 7(11), e48753. https://doi.org/10/
gf35cr
Ringelhan, S。, Wollersheim, J。, & Welpe, 我. 中号. (2015). I like, I cite?
Do Facebook likes predict the impact of scientific work? PLOS
ONE, 10(8),
e0134389. https://doi.org/10.1371/journal.pone.0134389
Robinson-García, N。, Torres-Salinas, D ., Zahedi, Z。, & Costas, 右.
(2014). New data, new possibilities: Exploring the insides of
Altmetric.com. El Profesional de La Informacion, 23(4),
359–366. https://doi.org/10/gf26gk
Roblyer, 中号. D ., McDaniel, M。, Webb, M。, Herman, J。, & Witty, J. V.
(2010). Findings on Facebook in higher education: A comparison
of college faculty and student uses and perceptions of social net-
working sites. The Internet and Higher Education, 13(3),
134–140. https://doi.org/10/fqwg8c
Selwyn, 氮. (2009). Faceworking: Exploring students’ education-re-
lated use of Facebook. 学习, Media and Technology, 34(2),
157–174. https://doi.org/10/dj9fq2
Thelwall, M。, Haustein, S。, Larivière, 五、, & Sugimoto, C. 右. (2013).
Do altmetrics work? Twitter and ten other social web services.
PLOS ONE, 8(5), e64841. https://doi.org/10/q6g
Thelwall, M。, & Wilson, 磷. (2014). Distributions for cited articles
from individual subjects and years. Journal of Informetrics, 8(4),
824–839. https://doi.org/10/f6qxsd
推特. (2019). Number of monthly active Twitter users worldwide
from 1st quarter 2010 to 1st quarter 2019 (in millions). Retrieved
从 [图形]. In Statista website: https://www.statista.com/statis-
tics/282087/number-of-monthly-active-twitter-users/
联合国. (2019). World Population Prospects 2019: Ten Key
发现. Retrieved from https://population.un.org/wpp/
Publications/Files/ WPP2019_10KeyFindings.pdf
Van Noorden, 右. (2014). Online collaboration: Scientists and the
social network. Nature News, 512(7513),
126. https://doi.org/10/t6v
Wass, J. (2016). URLs and DOIs: A complicated relationship
[网站]. Retrieved May 6, 2019, from Crossref website:
https://www.crossref.org/ blog/urls-and-dois-a-complicated-
relationship/
Wass, J. (2018). Some thoughts on “General discussion of data
quality challenges in social media metrics.” Joe’s Blog.
Retrieved July 16, 2018, from Joe’s Blog website: https://blog.
afandian.com/2018/05/zahedi-costas-altmetrics/
Xia, F。, Su, X。, 王, W., 张, C。, Ning, Z。, & 李, 我. (2016).
Bibliographic analysis of Nature based on Twitter and
Facebook altmetrics data. PLOS ONE, 11(12),
e0165997. https://doi.org/10/gf26jz
Zahedi, Z。, & Costas, 右. (2018A). Challenges in the quality of so-
cial media data across altmetric data aggregators. 科学,
技术, and Innovation Indicators in Transition (STI
2018 Conference Proceedings) (PP. 1553–1557). Leiden
大学.
Zahedi, Z。, & Costas, 右. (2018乙). General discussion of data quality
challenges in social media metrics: Extensive comparison of four
major altmetric data aggregators. PLOS ONE, 13(5),
e0197326. https://doi.org/10/gdkbgc
Zahedi, Z。, Fenner, M。, & Costas, 右. (2014). How consistent are alt-
metrics providers? Study of 1000 PLOS ONE publications using
the PLOS ALM, Mendeley and Altmetric.com APIs [Data set].
https://doi.org/10.6084/m9.figshare.1041821.v2
Zahedi, Z。, Fenner, M。, & Costas, 右. (2015). Consistency among
altmetrics data provider/aggregators: What are the challenges?
Altmetrics Workshop, 十月 9, 2015, Amsterdam Science
公园, 阿姆斯特丹. Retrieved from https://core.ac.uk/display/
92625603
Zuboff, S. (2015). Big other: Surveillance capitalism and the pros-
pects of an information civilization. Journal of Information
技术, 30(1), 75–89. https://doi.org/10/gddxpv
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
Quantitative Science Studies
768
How much research shared on Facebook happens outside of public pages and groups?
APPENDIX A
Table A1. Numeric values of the coverage of disciplines for AES, 销售点, and TW as displayed in
数字 3 including the proportion of all articles
Discipline
Clinical Medicine
销售点
AES
(覆盖范围)
(覆盖范围)
9,668 (32.9%) 4,630 (15.8%) 20,387 (69.4%)
TW
(覆盖范围)
All articles
(percentage)
29,360 (50.7%)
Biomedical Research
4,554 (31.7%) 1,760 (12.3%) 10,379 (72.3%)
14,351 (24.8%)
生物学
3,069 (45.4%) 1,355 (20.0%)
5,150 (76.2%)
6,761 (11.7%)
心理学
1,080 (64.2%)
515 (30.6%)
1,583 (94.2%)
1,681 (2.9%)
Engineering and
技术
314 (26.5%)
78 (6.6%)
634 (53.6%)
1,183 (2.0%)
Earth and Space
593 (54.0%)
327 (29.8%)
802 (73.0%)
1,098 (1.9%)
健康
567 (52.6%)
276 (25.6%)
893 (82.9%)
1,077 (1.9%)
社会科学
516 (70.5%)
256 (35.0%)
646 (88.3%)
732 (1.3%)
Physics
261 (42.4%)
73 (11.9%)
424 (68.8%)
616 (1.1%)
Professional Fields
297 (62.7%)
141 (29.7%)
416 (87.8%)
474 (0.8%)
Chemistry
83 (24.6%)
27 (8.0%)
150 (44.4%)
338 (0.6%)
Mathematics
74 (32.0%)
26 (11.3%)
144 (62.3%)
231 (0.4%)
全部的
21,076 (36.4%) 9,464 (16.3%) 41,608 (71.9%) 57,902 (100.0%)
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
Quantitative Science Studies
769
How much research shared on Facebook happens outside of public pages and groups?
APPENDIX B
Table B1. Proportion of articles found by the two different Facebook methods broken down into:
Found by AES-only (private posts), POS-only (public posts), and by both methods. This table reflects
the data in Figure 4
Discipline
Clinical Medicine
Any FB
10,864 6,234.0 (57.4%) 3,434.0 (31.6%) 1,196.0 (11.0%)
Only POS
Only AES
两个都
Biomedical Research
4,918
3,158 (64.2%)
1,396 (28.4%)
364 (7.4%)
生物学
心理学
健康
Earth and Space
社会科学
Engineering and Technology
Physics
Professional Fields
Chemistry
Mathematics
全部的
3,173
1,818 (57.3%)
1,251 (39.4%)
104 (3.3%)
1,135
620 (54.6%)
460 (40.5%)
55 (4.8%)
615
609
532
333
271
309
90
79
339 (55.1%)
228 (37.1%)
48 (7.8%)
282 (46.3%)
311 (51.1%)
16 (2.6%)
276 (51.9%)
240 (45.1%)
16 (3.0%)
255 (76.6%)
59 (17.7%)
19 (5.7%)
198 (73.1%)
63 (23.2%)
10 (3.7%)
168 (54.4%)
129 (41.7%)
12 (3.9%)
63 (70.0%)
20 (22.2%)
53 (67.1%)
21 (26.6%)
7 (7.8%)
5 (6.3%)
22928 13,464 (58.7%) 7,612 (33.2%)
1,852 (8.1%)
我
D
哦
w
n
哦
A
d
e
d
F
r
哦
米
H
t
t
p
:
/
/
d
我
r
e
C
t
.
米
我
t
.
/
e
d
你
q
s
s
/
A
r
t
我
C
e
–
p
d
我
F
/
/
/
/
1
2
7
4
9
1
8
8
5
8
1
3
q
s
s
_
A
_
0
0
0
4
4
p
d
/
.
F
乙
y
G
你
e
s
t
t
哦
n
0
7
S
e
p
e
米
乙
e
r
2
0
2
3
Quantitative Science Studies
770