lcor {LikertMakeR}

Rearrange columns in a data-frame to fit a predefined correlation matrix

Description

lcor_C() rearranges values in each column of a data-frame so that columns are correlated to match a predefined correlation matrix.

Usage

lcor(data, target)

Arguments

data

data-frame that is to be rearranged

target

target correlation matrix - should be a symmetric k*k positive-semi-definite matrix

Details

Values in a column do not change, so univariate statistics remain the same.

Value

Returns a dataframe whose column-wise correlations approximate a user-specified correlation matrix

Examples

## parameters
n <- 32
lowerbound <- 1
upperbound <- 5
items <- 5

mydat3 <- data.frame(
  x1 = lfast(n, 2.5, 0.75, lowerbound, upperbound, items),
  x2 = lfast(n, 3.0, 1.50, lowerbound, upperbound, items),
  x3 = lfast(n, 3.5, 1.00, lowerbound, upperbound, items)
)

cor(mydat3) |> round(3)

tgt3 <- matrix(
  c(
    1.00, 0.50, 0.75,
    0.50, 1.00, 0.25,
    0.75, 0.25, 1.00
  ),
  nrow = 3, ncol = 3
)

## apply function
new3 <- lcor(mydat3, tgt3)

## test output
cor(new3) |> round(3)