Nonparametric Interaction Tests in Balanced Two-Way ANOVA Models // Provides novel nonparametric tests, 'APCSSA' and 'APCSSM', for interaction in two-way ANOVA designs with balanced replications using all possible comparisons. These statistics extend previous methods, allow greater flexibility, and demonstrate higher power in detecting interactions for non- normal data. The package includes optimized functions for computing these test statistics, generating interaction plots, and simulating their null distributions. The companion package 'APCinteractionData' is available on 'GitHub' https://github.com/tranbaokhue/APCinteractionData. Methods are described and compared empirically in Tran, Wagaman, Nguyen, Jacobson, and Hartlaub (2024) doi:10.48550/arXiv.2410.04700.