Hypothesis Testing

Hypothesis Testing

1. Numerical

   • Normally Distributed
     • Mean + SD
       • independent samples
         • 2 samples (groups)
           • independent samples t test
             • Assumptions: independent samples, normal dist, same varience in samples from groups
         • >2 samples (groups
           • ANOVA
             • Assumptions: Independent samples, normal dist, same varience in each of the groups
         • 1 sample
           • One sample T test
             • Assumptions : 1 sample, normal dist
               • Difference of means
       • Paired samples
         • Paired T test
           • Assumptions: paired sample, normal dist
   • Skewed
     • Median and IQR
       • Independent samples
         • 2 samples (groups)
           • Mann-Whitley
             • Assumptions: independent samples, skewed dist in groups or ordinal
               • difference in distributions
         • >2 samples (groups)
           • Kruskal Wallis test
             • Asumptions: independent samples, skewed dist in at least 1 of groups or ordinal
       • Paired Samples
         • Wilcoxon matched pair test
           • Assumptions: paired samples, skewed dist in groups or ordinal
             • tendency for higher or lower (+ve/-ve rank)

2. Catagorical

   • Numerical Ordinal
   • Nominal, Ordinal, Binary
     • Proportion (or) percentage(s)
       • Independent samples
         • 2x2
           • Continuity correction Chi-squared test
             • Assumptions: no more than 20% of the cells have exp freq <5, 2 binary
               • association between
           • Fishers exact test
             • Assumptions: cont correction assump not met, 2 binary
         • >2x2
           • Pearsons Chi-squared test
             • Assumptions: same assumptions as cont corr
           • Chi squared test for trend
             • Assumptions: same as cont corr, ordinal data (at least 1)
       • Paired samples
         • 2x2
           • McNemar test
             • Assumptions: paired binary data
               • Means are equal/not equal