computeSSI: A function that computes Systematicity of Search Index (SSI)

In sonjaPerkovic/SSI: The package provides the function to compute the Systematicty of Search Index (SSI)

Description

Integrates all the necessary functions and computes the SSI. The number of alternatives, attributes, simulations and the minimum threshold for pattern length can be adjusted.

Usage

computeSSI(df, dfRan, participant, trial, alternative, attribute, num_alt,
  num_att, threshold, iter)

Arguments

df	Object of class data frame
dfRan	The same object used for creating random data.
participant	Identifies each unique subject.
trial	Identifies each unique trial.
alternative	Represents column with eye fixations to different alternatives.
attribute	Represents column with eye fixations to different attributes.
num_alt	Number of alternatives in the experiment.
num_att	Number of attributes in the experiment.
threshold	Sets the threshold for pattern length to two or four.
iter	Number of simulation iterations.

Value

A data set with all identified alternative- and attribute-wise patterns and a data set with all corresponding SSI values.

Author(s)

Sonja Perkovic, [e-mail]

Examples

#IMPORTANT! Variable names in your data set should match to the ones in the example below!

## Not run: 
df <- data.frame(participant = rep(c(1:50), each = 400),
                 trial = rep(c(1:200), each = 100),
                 alternative = sample(1:4, 20000, TRUE),
                 attribute = sample(c("a","b","c","d"), 20000, TRUE))

SSI <- computeSSI(df, df, "participant", "trial", "alternative", "attribute", 4, 4, 4, 1000)

## End(Not run)

sonjaPerkovic/SSI documentation built on May 29, 2019, 9:49 a.m.