c()の役割がわかりません

Question

前提・実現したいこと

https://note.com/marginal_ard30/n/nccfa34a503bd?magazine_key=m7af29eded997
このサイトの　（２）【研究２】コントロールグループの全回答の相関係数　の部分のc(3,4,5,6)はどういった役割なのか教えて下さい

> gayreshaped <- read.csv("gayreshaped.csv")
> ccap2012 <- read.csv("ccap2012.csv")

> dim(gayreshaped)
[1] 11948     6
> summary(gayreshaped)
     study                                                treatment        therm1      
 Min.   :1.000   No Contact                                    :6441   Min.   :  0.00  
 1st Qu.:1.000   Recycling Script by Gay Canvasser             :1046   1st Qu.: 48.00  
 Median :1.000   Recycling Script by Straight Canvasser        :1039   Median : 52.00  
 Mean   :1.204   Same-Sex Marriage Script by Gay Canvasser     :2389   Mean   : 58.43  
 3rd Qu.:1.000   Same-Sex Marriage Script by Straight Canvasser:1033   3rd Qu.: 84.00  
 Max.   :2.000                                                         Max.   :100.00                                                                                         

     therm2           therm3           therm4      
 Min.   :  0.00   Min.   :  0.00   Min.   :  0.00  
 1st Qu.: 45.00   1st Qu.: 44.00   1st Qu.: 44.00  
 Median : 55.00   Median : 57.00   Median : 58.00  
 Mean   : 58.68   Mean   : 59.72   Mean   : 59.76  
 3rd Qu.: 84.00   3rd Qu.: 85.00   3rd Qu.: 85.00  
 Max.   :100.00   Max.   :100.00   Max.   :100.00  
 NA's   :1351     NA's   :9835     NA's   :9777 
   
> dim(ccap2012)
[1] 43998     3
> summary(ccap2012)
       X             caseid          gaytherm     
 Min.   :    1   Min.   :   1.0   Min.   :  0.00  
 1st Qu.:11000   1st Qu.: 251.0   1st Qu.: 45.00  
 Median :22000   Median : 501.0   Median : 54.00  
 Mean   :22000   Mean   : 500.5   Mean   : 58.71  
 3rd Qu.:32999   3rd Qu.: 751.0   3rd Qu.: 85.00  
 Max.   :43998   Max.   :1001.0   Max.   :100.00  
                                  NA's   :3097  

> cor(gayreshaped$therm1[gayreshaped$study == 1 & gayreshaped$treatment == "No Contact"],
+     gayreshaped$therm2[gayreshaped$study == 1 & gayreshaped$treatment == "No Contact"],
+     use = "complete.obs")
[1] 0.9975817

> gayreshaped_2 <- gayreshaped[gayreshaped$study == 2 & gayreshaped$treatment == "No Contact",c(3,4,5,6)]


> cor(gayreshaped_2,use = "pairwise.complete.obs")
          therm1    therm2    therm3    therm4
therm1 1.0000000 0.9734449 0.9594085 0.9709017
therm2 0.9734449 1.0000000 0.9308287 0.9436621
therm3 0.9594085 0.9308287 1.0000000 0.9343249
therm4 0.9709017 0.9436621 0.9343249 1.0000000

> min(cor(gayreshaped_2,use = "pairwise.complete.obs"))
[1] 0.9308287

Comments

[y_waiwai]

これだけではなんともいえません。
コードをすべて提示しましょう

Answer 1

df[X,Y]

これはデータフレームから所定の行/列を抜き出す（スライスする）ときの基本形です。
Yには列条件を指定します。列条件には任意の条件式を置けますが、列番号を並べたベクトルを指定すると、それらの列を抽出することになります。c()はベクトルを作る関数です。df[,c(3,4,5,6)]はdfの3,4,5,6列目のみを取り出すということです。