Types of Data and Grouping Data

UNIT 1 prep

Independent groups

Equal participants are randomly allocated to the two groups. For example, the control group does math problems, and the experimental group does them after coffee.

Matched participants

subjects are selected to match key characteristics in control and experiment groups. Example: smoker and non-smoker groups

Repeated Measures

 Each participant is part of the control and experiment groups. Counterbalancing is needed to avoid the order effect. For example, sleep with or sleep without music.

Nominal

data is qualitative, with no ranking or order. Example: hair colour or religion

Ordinal

data that has a sequence but irregular gaps between levels. Example: the ages of people or the body mass/weight

Interval

Steps in the scale are evenly placed but zero does not mean zero. Example: temperature

Ratio

 Steps in the scale are evenly placed and zero means zero. Example: Length or time