文献计量学系列36: 主题战略坐标图
一、战略坐标图简介
战略坐标图以密度（Density Index）为纵坐标，以向心度（Centrality Index）为横坐标而构建的二维图（图1）。密度代表单个主题内部基本知识单元的联系强度。若某主题密度值越大，则表明该主题成熟度越高。向心度代表某主题与其他主题的联系强度。若某主题向心度值越大，则表明该主题与其他主题联系较为紧密，且该主题处于所有研究主题的核心位置。根据密度值和向心度值将直角坐标系分为四个象限，第一象限为motor themes，成熟度高的核心主题；第二象限为developed and isolated themes，成熟度高的孤立主题；第三象限emerging or disappearing themes，新主题或即将消失的主题；第四象限为basic and transversal themes，成熟度低的基础主题，该主题可能成为研究热点或未来发展的趋势。
图1 战略坐标图
（Cobo 等, 2011）
二、thematicMap函数简介
表1 thematicMap函数参数
三、加载包和导入数据
pacman::p_load(bibliometrix, rio)m1_TE <- import(file = 'E:/精鼎统计/m1_TE.xlsx')rownames(m1_TE) <- m1_TE$SRm1_TE$ID <- m1_TE$DE_TM
四、战略坐标图及其相关信息
主题战略坐标图：
thm <- thematicMap(M = m1_TE, field = 'ID', n = 250, stemming = F, size = 0.5, n.labels = 3, repel = TRUE)plot(thm$map)
图1 主题战略坐标图
主题战略坐标图的其他相关信息：
head(thm$clusters)# centrality density rcentrality rdensity label color name freq# 1 24.77495 50.55753 4 3 1 #E41A1C80 catchment 1410# 2 22.28983 56.49720 2 4 2 #377EB880 stable-isotope 1466# 3 22.71192 49.83792 3 2 3 #4DAF4A80 runoff 922# 4 16.28258 42.25561 1 1 4 #984EA380 groundwater 528# words# 1 catchment 205\nrunoff-generation 103\nmodel 94\ntracer 93\nforest 58\ngeneration 52\nflowpath 47\ntransport 46\nheadwater 40\nresidence-time 38# 2 stable-isotope 150\nprecipitation 106\nbasin 87\nriver 85\noxygen-stable-isotope 80\ndeuterium 75\nsnowmelt 60\nglacier 42\nmountain 42\nstreamflow 38# 3 runoff 149\nsoil 82\nstorm 82\nstream 49\nchemistry 48\ndissolved 22\nnitrate 21\nnitrogen 19\nwatershed 19\nuncertainty 18# 4 groundwater 123\nflow 79\ndischarge 32\nrecharge 31\nhydrochemistry 23\nbaseflow 21\nmass-balance 17\ngeochemistry 14\nrecession 14\nexchange 12# name_full# 1 catchment\nrunoff-generation\nmodel# 2 stable-isotope\nprecipitation\nbasin# 3 runoff\nsoil\nstorm# 4 groundwater\nflow\ndischargehead(thm$word)# Occurrences Words Cluster Color Cluster_Label# 1 205 catchment 1 #E41A1C80 catchment# 6 103 runoff-generation 1 #E41A1C80 catchment# 7 94 model 1 #E41A1C80 catchment# 8 93 tracer 1 #E41A1C80 catchment# 17 58 forest 1 #E41A1C80 catchment# 18 52 generation 1 #E41A1C80 catchmentthm$nclust# [1] 4head(thm$TOPIC)# [1] "catchment;catchment;stable-isotope;stable-isotope;stable-isotope;stable-isotope;runoff;runoff;runoff;groundwater;groundwater;groundwater;groundwater;groundwater;" # [2] "catchment;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;runoff;" # [3] "catchment;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;runoff;groundwater;" # [4] "catchment;catchment;catchment;catchment;catchment;stable-isotope;runoff;runoff;runoff;runoff;groundwater;groundwater;" # [5] "catchment;catchment;catchment;catchment;catchment;catchment;catchment;stable-isotope;stable-isotope;runoff;" # [6] "stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;stable-isotope;runoff;groundwater;groundwater;"
五、小结
六、参考文献
1. Aria, M., Misuraca, M. and Spano, M.(2020). Mapping the Evolution of Social Research and Data Science on30 Years of Social Indicators Research. Soc. Indic. Res. 149(3), 803-831. https://10.1007/s11205-020-02281-3.
2. Cobo, M.J., López-Herrera, A.G.,Herrera-Viedma, E. and Herrera, F. (2011). An approach for detecting,quantifying, and visualizing the evolution of a research field: A practicalapplication to the fuzzy sets theory field. Journal of Informetrics 5(1),146-166. https://10.1016/j.joi.2010.10.002.