Fast Interaction 1.5.0 Now Available!
Fast Interaction is free software that conducts regression analyses to determine if two continuous variables interact to predict a criterion variable. Fast Interaction automatically mean centers the predictor variables and creates the corresponding product term predictors. Results are presented in a table and a 2-D/3-D graph. Simple-slope lines are calculated and displayed in the context of the 3-D surface. Watch the video to the right for an overview. I suggest clicking the button in the lower right of the frame to view it in fullscreen mode. Fast Interaction is a free download on the Mac App Store.
Version 1.5.0 includes a new easy to use interface.
Fast Interaction 1.50 requires Mac OSX 10.10 (Yosemite) or higher.
Fast Interaction Calculations
How does Fast Interaction perform calculations? Fast Interaction uses the BLAS library in Apple's Accelerate framework and the LAPACK library. Links to the sample data file and R code which reproduces the numbers in Fast Interaction are presented below. Note, however, that Fast Interaction does not use R to perform calculations.
Download sample data: here
Download R file to check calculations: here
Download sample report with Fast Interaction output: here