CHOOSING A STATISTICAL TEST
Decision 1: Difference Or Correlation
Depending on type of hypothesis
Decision 2: Experimental Design
Independent Groups = unrelated
Repeated Measures & Matched Pairs = related
Decision 3: Levels Of Measurement
→ Interval Data
Differences between measurements, but no true zero
e.g. temperature in Degrees Celcius
→ Ordinal Data
Ordered categories (rankings, order or scalings)
e.g. service quality rating, student letter grades (differently sized gaps between each)
→ Nominal Data
Categories (no ordering or direction)
e.g. marital status, type of car owned
Decision 1: Difference Or Correlation
Depending on type of hypothesis
Decision 2: Experimental Design
Independent Groups = unrelated
Repeated Measures & Matched Pairs = related
Decision 3: Levels Of Measurement
→ Interval Data
Differences between measurements, but no true zero
e.g. temperature in Degrees Celcius
→ Ordinal Data
Ordered categories (rankings, order or scalings)
e.g. service quality rating, student letter grades (differently sized gaps between each)
→ Nominal Data
Categories (no ordering or direction)
e.g. marital status, type of car owned