bibliometrix (version 1.8)

KeywordGrowth: Yearly occurrences of top keywords/terms

Description

It calculates yearly occurrences of top keywords/terms.

Usage

KeywordGrowth(M, Tag = "ID", sep = ";", top = 10, cdf = TRUE)

Arguments

M

is a data frame obtained by the converting function convert2df. It is a data matrix with cases corresponding to articles and variables to Field Tag in the original ISI or SCOPUS file.

Tag

is a character object. It indicates one of the keyword field tags of the standard ISI WoS Field Tag codify (ID or DE) or a field tag created by termExtraction function (TI_TM, AB_TM, etc.).

sep

is the field separator character. This character separates strings in each keyword column of the data frame. The default is sep = ";".

top

is a numeric. It indicates the number of top keywords to analize. The default value is 10.

cdf

is a logical. If TRUE, the function calculates the cumulative occurrences distribution.

Value

an object of class data.frame

Examples

# NOT RUN {
data(scientometrics)
topKW=KeywordGrowth(scientometrics, Tag = "ID", sep = ";", top=5, cdf=TRUE)
topKW

# Plotting results
# 
# library(reshape2)
# library(ggplot2)
# DF=melt(topKW, id='Year')
# ggplot(DF,aes(Year,value, group=variable, color=variable))+geom_line()

# }