selmod: Selecting the mode.
In CA3variants: Three-Way Correspondence Analysis Variants

selmod

R Documentation

Selecting the mode.

Description

Select the mode in which the column has to be sign reversed. Below is an heuristic algorithm but a fully rational choice is hard to come by. Maximal number of sign reversals = p+q+r-2, but this number can be much smaller. Sign reverse a component, determine which if any of p, q and r is available for reversal. If one of them is wholly positieve way never choose it, else if one is wholly negative choose that one from A, B, C respectively; else if there is a component with a largest absolute value which is negative choose that one, or the one from A,B,C in that order; else choose the column of the longest mode; end if FreeA, FreeB, FreeC = 0 component is not available; = 1 component is available.

Usage

selmod(aptr, bptr, cptr, posptrA, negptrA, bigptrA, posptrB, negptrB, bigptrB, 
posptrC, negptrC, bigptrC, IA, IB, IC, I, J, K, p, q, r, longest)

Arguments

`aptr`	The pointer to the first component matrix.
`bptr`	The pointer to the second component matrix.
`cptr`	The pointer to the third component matrix.
`posptrA`	The pointer to the positive component of the first component matrix.
`negptrA`	The pointer to the negative component of the first component matrix.
`bigptrA`	The pointer to the biggest component (a larger negative positive value than a positive one) of the first component matrix.
`posptrB`	The pointer to the positive component of the first component matrix.
`negptrB`	The pointer to the negative component of the second component matrix.
`bigptrB`	The pointer to the biggest component (a larger negative positive value than a positive one) of the second component matrix.
`posptrC`	The pointer to the positive component of the third component matrix.
`negptrC`	The pointer to the negative component of the third component matrix.
`bigptrC`	The pointer to the biggest component (a larger negative positive value than a positive one) of the third component matrix.
`IA`	The pointer to the columns of the first component matrix, given the pointer to an element in core.
`IB`	The pointer to the columns of the second component matrix, given the pointer to an element in core.
`IC`	The pointer to the columns of the third component matrix, given the pointer to an element in core.
`I`	The row number of the three-way contingency table.
`J`	The column number of the three-way contingency table.
`K`	The tube number of the three-way contingency table.
`p`	The dimension number of the first mode.
`q`	The dimension number of the second mode.
`r`	The dimension number of the third mode.
`longest`	The component matrix of the longest mode to change sign (when no special reason for selection could be found).

Value

`success`	The flag variable to indicate if one of the components has to be sign reversed.
`chgmode`	Select the mode (1, 2 or 3) in which the column has to be sign reversed.
`chgcomp`	The pointer to the columns of the component matrices (A, B or C) that are responsible for the value in the ordered core array.