fuse {iopsych}

Computes the correlation between two composites of items.

Description

Computes the correlation between two composites of items. Composites may contain overalapping items. Items weights for each composite may be specified.

Usage

fuse(r_mat, a, b, wt_a = rep(1, length(a)), wt_b = rep(1, length(b)))

Arguments

r_mat

A correlation matrix.

a

The items used for composite A specified as a vector of column numbers.

b

The items used for composite B specified as a vector of column numbers.

wt_a

A vector containing the weights of each item in composite A.

wt_b

A vector containing the weights of each item in composite B.

Value

A correlation coefficient.

Author(s)

Allen Goebl and Jeff Jones

References

Lord, F.M. & Novick, M.R. (1968). Statisticl theories of menal test scores., 97-98.

Examples

Rxx <- matrix(c(1.00, 0.25,  0.50,  0.61,
                0.25, 1.00,  0.30,  0.10,
                0.50, 0.30,  1.00, -0.30,
                0.61, 0.10, -0.30,  1.00), 4, 4)
a   <- c(1, 3)
b   <- c(2, 4)

# Example using overlapping items and weights
Rxx  <- matrix(.3, 4, 4); diag(Rxx) <- 1
a    <- c(1, 2, 4)
b    <- c(2, 3)
wt_a <- c(.60, .25, .15)
wt_b <- c(2, 3)

fuse(r_mat = Rxx, a = a, b = b, wt_a = wt_a, wt_b = wt_b)