Retrieving basic information

## Define the id for Richard Feynman
id <- 'B7vSqZsAAAAJ'

## Get his profile
l <- get_profile(id)

## Print his name and affliation
l$name
## [1] "Richard Feynman"
l$affiliation
## [1] "California Institute of Technology"
## Print his citation index
l$h_index
## [1] 60
l$i10_index
## [1] 95

Retrieving publications

get_publications() return a data.frame of publication records. It contains information of the publications, including title, author list, page number, citation number, publication year, etc..

The pubid is the article ID used by Google Scholar and the identifier that is used to retrieve the citation history of a selected publication.

## Get his publications (a large data frame)
p <- get_publications(id)
head(p, 3)
##                                    title
## 1 Quantum mechanics and path integration
## 2        The Feynman lectures on physics
## 3         TheFeynman lectures on physics
##                                                               author
## 1                                               RP Feynman, AR Hibbs
## 2                       RP Feynman, RB Leighton, M Sands, SB Treiman
## 3 RP Feynman, RB Leighton, M Sands, CA Heras, R Gómez, E Oelker, ...
##                                journal number cites year
## 1                          McGraw–Hill        28427 1965
## 2                        Physics Today 17, 45 15850 1964
## 3 Fondo Educativo Interamericano, cop.        15656 1971
##                                                                                                                                             cid
## 1                                                                                14769952204323476283,12549707430555464374,17914366645132260192
## 2                                                             14769952204323476283,15649786516955137750,3585810396644010165,3669163321259408309
## 3 14769952204323476283,10013291528877493387,14529335578020619748,10241317899299163575,788740732818767427,589298466617084428,4222687201833278212
##          pubid
## 1 hMod-77fHWUC
## 2 u-x6o8ySG0sC
## 3 SP6oXDckpogC

Retrieving citation data

## Get his citation history, i.e. citations to his work in a given year
ct <- get_citation_history(id)

## Plot citation trend
library(ggplot2)
ggplot(ct, aes(year, cites)) + geom_line() + geom_point()

Users can retrieve the citation history of a particular publication with get_article_cite_history().

## The following publication will be used to demonstrate article citation history
as.character(p$title[1])
## [1] "Quantum mechanics and path integration"
## Get article citation history
ach <- get_article_cite_history(id, p$pubid[1])

## Plot citation trend
ggplot(ach, aes(year, cites)) +
    geom_segment(aes(xend = year, yend = 0), size=1, color='darkgrey') +
    geom_point(size=3, color='firebrick')

Comparing scholars

You can compare the citation history of scholars by fetching data with compare_scholars.

# Compare Feynman and Stephen Hawking
ids <- c('B7vSqZsAAAAJ', 'qj74uXkAAAAJ')

# Get a data frame comparing the number of citations to their work in
# a given year
cs <- compare_scholars(ids)

## remove some 'bad' records without sufficient information
cs <- subset(cs, !is.na(year) & year > 1900)
ggplot(cs, aes(year, cites, group=name, color=name)) + geom_line() + theme(legend.position="bottom")

## Compare their career trajectories, based on year of first citation
csc <- compare_scholar_careers(ids)
ggplot(csc, aes(career_year, cites, group=name, color=name)) + geom_line() + geom_point() +
    theme(legend.position=c(.2, .8))

Visualizing and comparing network of coauthors

# Be careful with specifying too many coauthors as the visualization of the
# network can get very messy.
coauthor_network <- get_coauthors('amYIKXQAAAAJ&hl', n_coauthors = 7)

coauthor_network
##                        author                  coauthors
## 1  Herman G. Van De Werfhorst                  Thijs Bol
## 2  Herman G. Van De Werfhorst            Daniele Checchi
## 3  Herman G. Van De Werfhorst         Frank Van Tubergen
## 4  Herman G. Van De Werfhorst         István György Tóth
## 5  Herman G. Van De Werfhorst Jonathan Jan Benjamin Mijs
## 6  Herman G. Van De Werfhorst            Wiemer Salverda
## 7  Herman G. Van De Werfhorst          Gerbert Kraaykamp
## 8                   Thijs Bol Herman G. Van De Werfhorst
## 9                   Thijs Bol             Andrea Forster
## 10                  Thijs Bol         Arnout Van De Rijt
## 11                  Thijs Bol     Christina Ciocca Eller
## 12                  Thijs Bol              Jaap Dronkers
## 13                  Thijs Bol                Bram Lancee
## 14                  Thijs Bol              Kim A. Weeden
## 15            Daniele Checchi        Massimiliano Bratti
## 16            Daniele Checchi           Giorgio Brunello
## 17            Daniele Checchi              Vito Peragine
## 18            Daniele Checchi             Marco Leonardi
## 19            Daniele Checchi           Giuseppe Bertola
## 20            Daniele Checchi            Carlo V. Fiorio
## 21            Daniele Checchi Herman G. Van De Werfhorst
## 22         Frank Van Tubergen                 Ineke Maas
## 23         Frank Van Tubergen           Matthijs Kalmijn
## 24         Frank Van Tubergen Herman G. Van De Werfhorst
## 25         Frank Van Tubergen            Agnieszka Kanas
## 26         Frank Van Tubergen            Marcel Coenders
## 27         Frank Van Tubergen           Borja Martinovic
## 28         Frank Van Tubergen               Stijn Ruiter
## 29         István György Tóth Herman G. Van De Werfhorst
## 30         István György Tóth                   Ive Marx
## 31         István György Tóth            Daniele Checchi
## 32         István György Tóth                Brian Nolan
## 33         István György Tóth            Wiemer Salverda
## 34         István György Tóth               Tamás Keller
## 35         István György Tóth             Orsolya Lelkes
## 36 Jonathan Jan Benjamin Mijs Herman G. Van De Werfhorst
## 37 Jonathan Jan Benjamin Mijs               Maurice Crul
## 38 Jonathan Jan Benjamin Mijs               Bowen Paulle
## 39 Jonathan Jan Benjamin Mijs             Michele Lamont
## 40 Jonathan Jan Benjamin Mijs            Elyas Bakhtiari
## 41 Jonathan Jan Benjamin Mijs                Noam Gidron
## 42 Jonathan Jan Benjamin Mijs           Jaap Nieuwenhuis
## 43            Wiemer Salverda                Brian Nolan
## 44            Wiemer Salverda                   Ive Marx
## 45            Wiemer Salverda           Lucifora Claudio
## 46            Wiemer Salverda            Daniele Checchi
## 47            Wiemer Salverda Herman G. Van De Werfhorst
## 48            Wiemer Salverda              Stephen Bazen
## 49            Wiemer Salverda         István György Tóth
## 50          Gerbert Kraaykamp          Nan Dirk De Graaf
## 51          Gerbert Kraaykamp           Paul M. De Graaf
## 52          Gerbert Kraaykamp           Matthijs Kalmijn
## 53          Gerbert Kraaykamp                 Tim Huijts
## 54          Gerbert Kraaykamp          Christiaan Monden
## 55          Gerbert Kraaykamp         Maarten Hj Wolbers
## 56          Gerbert Kraaykamp         Maurice Gesthuizen

And then we have a built-in function to plot this visualization.

plot_coauthors(coauthor_network)

Note however, that these are the coauthors listed in Google Scholar profile and not coauthors from all publications.