STATISTICAL TESTS
INDEPENDENT T-TEST
Two conditions
Different subjects
eg 1: gender
male
female
eg 2: teeth location
mandibular
maxillary
Parametric test
DEPENDENT T-TEST
Two conditions
before
after
Same subjects
eg 1: gender
male
eg 2: marital status
single
Parametric test
ONE-WAY ANOVA
3 or more samples
Unpaired/independent sample
From normal distribution
Parametric test
TWO-WAY ANOVA
Samples normally distributed
Same sample size
Parametric test
Unpaired/independent sample
MANN-WHITNEY TEST
2 independent samples
Not normally distributed
Non-parametric test
REGRESSION
Models
one dependent
one independent
Equation
Y = a + bX
R2 - coefficient of determination
Prediction
CORRELATION
Relationship between variables
positive or negative relationship
strength of relationship
Pearson's product-moment
interval variable
approximately normally distributed
Spearman's rank
ordinal or interval variable
not normally distributed
CHI SQUARE TEST
Only one sample
Non-parametric test
Not normally distributed
Characteristics
random sampling method
categorical variable
displayed in contingency table
nominal data
KRUSKAL-WALLIS
3 or more samples
Unpaired/independent samples
Not normally distributed
WILCOXON SIGNED RANK TEST
2 dependent samples
Not normally distributed
Non-parametric test