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rr-lavaan

lavaan: Correlation between each pair of variables

I have several variables, say X1 to Xn, and I want to include correlation between each pair of them in my SEM (I use lavaan package for R software).

I know I can specify

X1 ~~ X2+X3+...+Xn
X2 ~~ X3+X4+...+Xn
X3 ~~ X4+X5+...+Xn

and so on.

Is there any shorter way to achieve this?

Solution

  • If you just want to create the calls, you could try this:

    sub("\\+",  " ~~ ", sapply(1:10, function(i) paste(paste0("X", i:10), collapse = " + ")))

 [1] "X1  ~~  X2 + X3 + X4 + X5 + X6 + X7 + X8 + X9 + X10" "X2  ~~  X3 + X4 + X5 + X6 + X7 + X8 + X9 + X10"     
 [3] "X3  ~~  X4 + X5 + X6 + X7 + X8 + X9 + X10"           "X4  ~~  X5 + X6 + X7 + X8 + X9 + X10"               
 [5] "X5  ~~  X6 + X7 + X8 + X9 + X10"                     "X6  ~~  X7 + X8 + X9 + X10"                         
 [7] "X7  ~~  X8 + X9 + X10"                               "X8  ~~  X9 + X10"                                   
 [9] "X9  ~~  X10"                                         "X10"

    Perhaps you may want to delete the last element, "X10", and of course you could replace 10 by the N of your data.