A researcher investigates the effect of sleep deprivation on reaction times (measured in milliseconds) using two independent groups of participants. The researcher wants to perform a parametric test (an unrelated ttt-test) to analyse the differences between the groups.
Which of the following scenarios would prevent the researcher from performing this parametric test?
The standard deviations of the reaction times for both groups are approximately equal.
The reaction times are measured on a continuous millisecond scale, providing ratio level data.
The distribution of reaction times in the sleep-deprived group is found to be highly skewed.
The number of participants in each of the two groups is equal.
644 exam-style questions on OCR A Level Psychology Research methods and techniques. Each one has a worked solution and a mark scheme showing where the marks go.