Task 7 sleep validation and inquiry

Subjective quantitative measure’s reliability?

• Low test-retest reliability

• Tool has not been tested long enough to be deemed reliable

Define reliability (1 mark)

• Reliability is the degree to which a measurement tool produces consistent results.

Explain one limitation of correlational data in a non-experimental manner (2 marks)

• There is a correlation found from the study but is false to assume that correlation is equal to causation, as there is no cause-effect relationship that can be sourced from non-experimental correlational studies. 

Suggest a change that could be made to improve external validity in this study. Justify how this change would improve validity. (3 marks)

• Could increase sample size to include a more diverse range of participant characteristics like age, ethnicity ect.

• This increases validity as the sample is more representative of the population, therefore is generalisable (results are relevant and can be applied to the population)

Evaluate which measure of central tendency would be the most appropriate for this data set. (3 marks)

• The mean contains a value not present in data set

• The median for each value is in the original data set

• Therefore median is most appropriate

• However, if outliers are present, mean is appropriate

Evaluate the purpose for creating a standardised procedure and instructions for a psychological study (3 marks)

• Minimises extraneous and cofounding variables

• Ensures all participants have the same controlled environment

• This means that when replicated with a larger sample size, results should be reliable.

Outline one strength and one limitation of a subjective quantitative measurement tool (2 marks)

• One strength is that quantitative data can be statistically analysed.

• A limitation is that it does not allow for reasoning of given results.