EMSA Revision 2 Quantification - Taking human behaviour and coding it numerically. Variables (things that change) - Variables can either be categorical (belonging to a group) or continuous (along a scale) Hypothetical construct (psychological variable) - Explanatory variable which is not directly observable. We must operationalise variables in order to give an accurate and reliable measure. They should be reliable (if you test the same people in similar circumstances you will achieve similar results - test- retest reliability) and valid (measure what you actually set out to measure). Causal relationship - one variable causes change to another variable. Confounding variables are uncontrolled variables that may provide an alternative explanation. True experiment - Random allocation and control over the variables. Independent variables is composed of 'levels', which is the number of conditions or groups in the IV. If there are different people in each level of the IV, it is called independent samples (between participants). If the same people are completing each level of the IV it is called repeated measures (within participants). Independent sample/between participants - Advantages: . Do not take part in both so less likely to guess the aims · No fatigue effects (order effects) · Do not need to produce more stimuli Disadvantages: · Individual differences (more or less likely to swear than the other group) · Need more participants Repeated measures/within participants - Advantages: · Need fewer participants · No individual differences Disadvantages: · Order effects - Stop by counterbalancing (ABBA) · May guess the aims However, counterbalancing can sometimes result in asymmetric effects. For example, if A is an easy task and B is difficult. People in condition A may do well in the easy task and be able to apply it to the more difficult task therefore doing better in both. Whilst, people in condition B may struggle with the more difficult task first and not know what to do, therefore doing badly.
Matched pairs design: Advantages - · No order effects