TransEntro {GrpString}

Transition entropy of a group of strings

Description

TransEntro computes the overall transition entropy of all the strings in a group.

Usage

TransEntro(strings.vec)

Arguments

strings.vec

String Vector.

Details

Entropy is calculated using the Shannon entropy formula: -sum(freqs * log2(freqs)). Here, freqs are transition frequencies, which are the values in the normalized transition matrix exported by function TransMx in this package. The formula is equivalent to the function entropy.empirical in the 'entropy' package when unit is set to log2.

Value

Returns a single number.

Note

Strings with less than 2 characters are not included for computation of entropy.

References

I. Hooge; G. Camps. (2013) Scan path entropy and arrow plots: capturing scanning behavior of multiple observers. Frontiers in Psychology.

See Also

TransEntropy, TransMx

Examples

# simple strings
stra.vec <- c("ABCDdefABCDa", "def123DC", "A", "123aABCD", "ACD13", "AC1ABC", "3123fe")
TransEntro(stra.vec)