====== Tools ======
  * [[https://webpower.psychstat.org/models/kurtosis/|Univariate and multivariate skewness and kurtosis]] (Old version)
  * [[https://webpower.psychstat.org/models/nonnormal/|Normality evaluation of real data]] (New version)
  * [[https://webpower.psychstat.org/models/convertdata/|Convert data among TXT, CSV, SAS, SPSS, STATA and Excel]]
  * [[https://webpower.psychstat.org/models/bass/|Bass-Ackward Factor Analysis]]