Type:	Package
Title:	Analyse Citation Data from Google Scholar
Version:	0.2.5
Maintainer:	Guangchuang Yu <guangchuangyu@gmail.com>
Description:	Provides functions to extract citation data from Google Scholar. Convenience functions are also provided for comparing multiple scholars and predicting future h-index values.
Depends:	R (≥ 4.1.0)
Imports:	R.cache, dplyr, httr, rlang, rvest, stringr, xml2, tidygraph, ggraph, ggplot2
Suggests:	knitr, rmarkdown, prettydoc, roxygen2, spelling, testthat (≥ 2.1.0), yulab.utils
VignetteBuilder:	knitr
License:	MIT + file LICENSE
URL:	https://github.com/YuLab-SMU/scholar
BugReports:	https://github.com/YuLab-SMU/scholar/issues
RoxygenNote:	7.3.2
Encoding:	UTF-8
Language:	en-GB
NeedsCompilation:	no
Packaged:	2025-06-26 07:42:06 UTC; HUAWEI
Author:	Guangchuang Yu [aut, cre], James Keirstead [aut], Gregory Jefferis [aut], Gordon Getzinger [ctb], Jorge Cimentada [ctb], Max Czapanskiy [ctb], Dominique Makowski [ctb]
Repository:	CRAN
Date/Publication:	2025-06-26 08:10:02 UTC

scholar

Description

The scholar package provides functions to extract citation data from Google Scholar. There are also convenience functions for comparing multiple scholars and predicting h-index scores based on past publication records.

Google Scholar cookies

Google does not encourage people to use the scholar website as an API. You will find a number of issues related to this if you follow: https://github.com/jkeirstead/scholar/issues?q=is:issue+cookie

If you try to fetch too many pages, you can expect to see your access to scholar blocked. One step that they do take is to provide a session cookie. Reusing these seems to help. If you wish to write your own code to interact with Google Scholar, we recommend that you use the get_scholar_resp function to carry out the query.

Author(s)

Maintainer: Guangchuang Yu guangchuangyu@gmail.com (ORCID)

Authors:

• James Keirstead james.keirstead@gmail.com

• Gregory Jefferis jefferis@gmail.com (ORCID)

Other contributors:

• Gordon Getzinger [contributor]

• Jorge Cimentada cimentadaj@gmail.com [contributor]

• Max Czapanskiy maxczapanskiy@gmail.com [contributor]

• Dominique Makowski dom.makowski@gmail.com [contributor]

Source

The package reads data from https://scholar.google.com. Dates and citation counts are estimated and are determined automatically by a computer program. Use at your own risk.

See Also

Useful links:

• https://github.com/YuLab-SMU/scholar

• Report bugs at https://github.com/YuLab-SMU/scholar/issues

Get author order.

Description

Get author rank in authors list.

Usage

author_position(authorlist, author)

Arguments

Value

dataframe with author's position and normalized position (a normalized index, with 0 corresponding, 1 to last and 0.5 to the middle. Note that single authorship will be considered as last, i.e., 1).

Author(s)

Dominique Makowski

Examples

## Not run: 
library(scholar)

id <- "DO5oG40AAAAJ"

authorlist <- scholar::get_publications(id)$author
author <- scholar::get_profile(id)$name

author_position(authorlist, author)

## End(Not run)

Compare the careers of multiple scholars

Description

Compares the careers of multiple scholars based on their citation histories. The scholar's career is defined by the number of citations to his or her work in a given year (i.e. the bar chart at the top of a scholar's profile). The function has an career option that allows users to compare scholars directly, i.e. relative to the first year in which their publications are cited.

Usage

compare_scholar_careers(ids, career = TRUE)

Arguments

Examples

  ## How do Richard Feynmann and Stephen Hawking compare?
  # Compare Feynman and Stephen Hawking
  ids <- c("B7vSqZsAAAAJ", "qj74uXkAAAAJ")
  df <- compare_scholar_careers(ids)

Compare the citation records of multiple scholars

Description

Compares the citation records of multiple scholars. This function compiles a data frame comparing the citations received by each of the scholar's publications by year of publication.

Usage

compare_scholars(ids, pagesize = 100)

Arguments

Value

a data frame giving the ID of each scholar and the total number of citations received by work published in a year.

Examples

## Not run: 
    ## How do Richard Feynmann and Stephen Hawking compare?
    ids <- c("B7vSqZsAAAAJ", "qj74uXkAAAAJ")
    df <- compare_scholars(ids)

## End(Not run)

format_authors

Description

This function converts first and middle names to initials

Usage

format_authors(string)

Arguments

format_publications

Description

Format publication list

Usage

format_publications(scholar.profile, author.name = NULL)

Arguments

Value

a vector of formated publications

Author(s)

R Thériault and modified by Guangchuang Yu

Examples

## Not run: 
 library(scholar)
 format_publications("DO5oG40AAAAJ")    

## End(Not run)

Gets the citation history of a single article

Description

Gets the citation history of a single article

Usage

get_article_cite_history(id, article)

Arguments

Value

a data frame giving the year, citations per year, and publication id

Gets the URL to the google scholar website of an article.

Description

Gets the URL to the google scholar website of an article.

Usage

get_article_scholar_url(id, pubid)

Arguments

Value

a String that contains the URL to the scholar website of the article

Get historical citation data for a scholar

Description

Gets the number of citations to a scholar's articles over the past nine years.

Usage

get_citation_history(id)

Arguments

Details

This information is displayed as a bar plot at the top of a standard Google Scholar page and only covers the past nine years.

Value

a data frame giving the number of citations per year to work by the given scholar

Gets the network of coauthors of a scholar

Description

Gets the network of coauthors of a scholar

Usage

get_coauthors(id, n_coauthors = 5, n_deep = 1)

Arguments

Details

Considering that scraping each publication for all coauthors is error prone, get_coauthors grabs only the coauthors listed on the google scholar profile (on the bottom right of the profile), not from all publications.

Value

A data frame with two columns showing all authors and coauthors.

See Also

plot_coauthors

Examples

## Not run: 

library(scholar)
coauthor_network <- get_coauthors('amYIKXQAAAAJ')
plot_coauthors(coauthor_network)

## End(Not run)

Get the Complete list of authors for a Publication

Description

Found as Muhammad Qasim Pasta's solution here https://github.com/jkeirstead/scholar/issues/21

Usage

get_complete_authors(id, pubid, delay = 0.4, initials = TRUE)

Arguments

Value

a string containing the complete list of authors

Author(s)

Muhammad Qasim Pasta

Abram B. Fleishman

James H. Conigrave

Get journal ranking.

Description

Get journal ranking for a journal list.

Usage

get_journalrank(journals, max.distance = 0.05)

Arguments

Value

Journal ranking data.

Author(s)

Dominique Makowski and Guangchuang Yu

Examples

## Not run: 
library(scholar)

id <- get_publications("bg0BZ-QAAAAJ&hl")
impact <- get_journalrank(journals=id$journal)

id <- cbind(id, impact)

## End(Not run)

Calculates how many articles a scholar has published

Description

Calculate how many articles a scholar has published.

Usage

get_num_articles(id)

Arguments

Value

an integer value (max 100)

Gets the number of distinct journals in which a scholar has published

Description

Gets the number of distinct journals in which a scholar has published. Note that Google Scholar doesn't provide information on journals per se, but instead gives a title for the containing publication where applicable. So a journal here might actually be a journal, a book, a report, or some other publication outlet.

Usage

get_num_distinct_journals(id)

Arguments

Value

the number of distinct journals

Gets the number of top journals in which a scholar has published

Description

Gets the number of top journals in which a scholar has published. The definition of a 'top journal' comes from Acuna et al. and the original list was based on the field of neuroscience. This function allows users to specify that list for themselves, or use the default Acuna et al. list.

Usage

get_num_top_journals(id, journals)

Arguments

Source

DE Acuna, S Allesina, KP Kording (2012) Future impact: Predicting scientific success. Nature 489, 201-202. doi:10.1038/489201a.

Gets the year of the oldest article for a scholar

Description

Gets the year of the oldest article published by a given scholar.

Usage

get_oldest_article(id)

Arguments

Value

the year of the oldest article

Gets profile information for a scholar

Description

Gets profile information for a researcher from Google Scholar. Each scholar profile page gives the researcher's name, affiliation, their homepage (if specified), and a summary of their key citation and publication availability metrics. The scholar ID can be found by searching Google Scholar at http://scholar.google.com.

Usage

get_profile(id)

Arguments

Value

a list containing the scholar's name, affiliation, citations, impact and publication availability metrics, research interests, homepage and coauthors.

Metrics include:

• total_cites combined citations to all publications

• h_index the largest number h such that h publications each have at least h citations

• i10_index the number of publications that each have at least 10 citations

• available the number of publications that have a version online that can be read for free (though not necessarily reusable under an open access license)

• not_available the number of publications only available behind a paywall

Examples

{
   ## Gets profiles of some famous physicists
   ids <- c("xJaxiEEAAAAJ", "qj74uXkAAAAJ")
   profiles <- lapply(ids, get_profile)
}

Gets the abstract for a publication id.

Description

Gets the abstract for a publication id.

Usage

get_publication_abstract(id, pub_id, flush = FALSE)

Arguments

Value

a String that contains the abstract of the publication.

Gets the full data for a publication

Description

Gets the full data for a publication

Usage

get_publication_data_extended(id, pub_id, flush = FALSE)

Arguments

Value

a list that contains the full data

Gets the full date for a publication

Description

Gets the full date for a publication

Usage

get_publication_date(id, pub_id, flush = FALSE)

Arguments

Value

a String that contains the publication date

Gets the PDF URL for a publication id.

Description

Gets the PDF URL for a publication id.

Usage

get_publication_url(id, pub_id, flush = FALSE)

Arguments

Value

a String that contains the URL to the PDF of the publication.

Gets the publications for a scholar

Description

Gets the publications of a specified scholar.

Usage

get_publications(
  id,
  cstart = 0,
  cstop = Inf,
  pagesize = 100,
  flush = FALSE,
  sortby = "citation"
)

Arguments

Details

Google uses two id codes to uniquely reference a publication. The results of this method includes cid which can be used to link to a publication's full citation history (i.e. if you click on the number of citations in the main scholar profile page), and pubid which links to the details of the publication (i.e. if you click on the title of the publication in the main scholar profile page.)

Value

a data frame listing the publications and their details. These include the publication title, author, journal, number, cites, year, and two id codes (see details).

Search for Google Scholar ID by name and affiliation

Description

Search for Google Scholar ID by name and affiliation

Usage

get_scholar_id(last_name = "", first_name = "", affiliation = NA)

Arguments

Value

Google Scholar ID as a character string.

Examples

get_scholar_id(first_name = "kristopher", last_name = "mcneill")

get_scholar_id(first_name = "michael", last_name = "sander", affiliation = NA)
get_scholar_id(first_name = "michael", last_name = "sander", affiliation = "eth")
get_scholar_id(first_name = "michael", last_name = "sander", affiliation = "ETH Zurich")
get_scholar_id(first_name = "michael", last_name = "sander", affiliation = "Mines")
get_scholar_id(first_name = "james", last_name = "babler")

Recursively try to GET a Google Scholar Page storing session cookies

Description

see scholar-package documentation for details about Scholar session cookies.

Usage

get_scholar_resp(url, attempts_left = 5)

Arguments

Value

an [response][httr::response] object

See Also

[GET][httr::GET]

Plot a network of coauthors

Description

Plot a network of coauthors

Usage

plot_coauthors(network, size_labels = 5)

Arguments

Value

a ggplot2 object but prints a plot as a side effect.

See Also

get_coauthors

Examples

## Not run: 
library(scholar)
coauthor_network <- get_coauthors('amYIKXQAAAAJ&hl')
plot_coauthors(coauthor_network)

## End(Not run)

Predicts the h-index for a researcher

Description

Predicts the h-index for a researcher each year for ten years into the future using Acuna et al's method (see source). The model was fit to data from neuroscience researchers with an h-index greater than 5 and between 5 to 12 years since publishing their first article. So naturally if this isn't you, then the results should be taken with a large pinch of salt.

Usage

predict_h_index(id, journals)

Arguments

Details

Since the model is calibrated to neuroscience researchers, it is entirely possible that very strange (e.g. negative) h-indices will be predicted if you are a researcher in another field. A warning will be displayed if the sequence of predicted h-indices contains a negative value or is non-increasing.

Value

a data frame giving predicted h-index values in future

Note

A scientist has an h-index of n if he or she publishes n papers with at least n citations each. Values returned are fractional so it's up to your own vanity whether you want to round up or down.

Source

DE Acuna, S Allesina, KP Kording (2012) Future impact: Predicting scientific success. Nature 489, 201-202. doi:10.1038/489201a. Thanks to DE Acuna for providing the full regression coefficients for each year ahead prediction.

Examples

  ## Predict h-index of original method author
## Not run: 
  id <- "DO5oG40AAAAJ"
  df <- predict_h_index(id)

## End(Not run)

set_scholar_mirror

Description

set scholar mirror

Usage

set_scholar_mirror(mirror = NULL)

Arguments

Details

setting google scholar mirror

Author(s)

Guangchuang Yu

Ensures that specified IDs are correctly formatted

Description

Ensures that specified IDs are correctly formatted

Usage

tidy_id(id)

Arguments