# con_hamming_holland: Congruence Index based on the Hamming distance In holland: Statistics for Holland's Theory of Vocational Choice

## Description

The function computes the location-weighted, cost-sensitive Hammig distance (Hamming, 1950).

## Usage

 `1` ```con_hamming_holland(a, b, costs = "hexa", weights = c(1.5, 1.25, 1)) ```

## Arguments

 `a` a character vector with person Holland codes. `b` a character vector with environment Holland codes. `costs` character with default set to `costs = "hexa"` to use a matrix with replacement costs based on the RIASEC structure for the calculation of the distance. `weights` a numeric vector with length equal to `a` and `b` assigning a weight to the places (1:6) of the letter-codes defined in `a` and `b`.

## Details

The function finds the distance according to Hamming (1950) between two sequences (see Abbott, 1995), which are the Holland codes given in argument a, which is the person code, and argument b, which is the environment code.

## Value

a numeric with value for congruence.

## References

Holland, J.L. 1963. A theory of vocational choice. I. Vocational images and choice. Vocational Guidance Quarterly, 11(4), 232–239.

Hamming, R. (1950). Error detecting and error correcting codes. Bell System Technical Journal, The, 29(2), 147–160.

Abbott, A. (1995, August). Sequence Analysis: New Methods for Old Ideas. Annual Review of Sociology, 21, 93–113.

## Examples

 ```1 2 3``` ```con_hamming_holland(a="RIA",b="SEC") # max. difference con_hamming_holland(a="RIA",b="RIA") # max. similarity con_hamming_holland(a="RIASEC",b="SECRIA", weights=c(1.5,1.25,1,0.75,0.5,0.25)) # max. difference ```

holland documentation built on Sept. 5, 2021, 5:08 p.m.