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9990 · 3.1.2

Research methodology — common mistakes

Common exam mistakes on 9990 Research methodology. Learn what loses marks, then practise the topic with Examiner’s Ink.

Exam tip 1

When evaluating a study in Paper 2, always link the type of experiment to its specific strengths and weaknesses. For a lab experiment, praise the high control over extraneous variables but criticise the artificiality and potential for demand characteristics.

Exam tip 2

When a question asks you to 'describe the observation' used in a core study, be precise. For example, state it was a 'covert, non-participant, structured observation' and justify each element with evidence from the study's procedure.

Exam tip 3

For Paper 2, you may be asked to suggest an alternative way to study something. If the original study used an experiment, suggesting a self-report method like a semi-structured interview is a valid alternative. Justify your choice by explaining how it would overcome a weakness of the original method (e.g., by providing insight into 'why' a behaviour occurred).

Exam tip 4

In Paper 2, if you are given a small data set, be prepared to calculate the mean, median, mode, or range. Always show your working. When asked to draw a conclusion, refer specifically to the descriptive statistics (e.g., 'The median score for Group A was 7, which is higher than the median of 4 for Group B, suggesting...').

Is a natural experiment the same as a field experiment?

No. A field experiment takes place in a natural setting, but the researcher still manipulates the Independent Variable (IV). In a natural experiment, the IV is an event or change that occurs naturally, without any intervention from the researcher (e.g., a change in law). The researcher simply records the effect of this change on a Dependent Variable (DV).

Can a study use both quantitative and qualitative data?

Yes, this is called a mixed-methods approach and is very common. For example, a questionnaire might use Likert scales to gather quantitative data on attitudes, and also include an open-ended question asking participants to explain their views, which provides rich qualitative data. This allows for both statistical analysis and a deeper, more nuanced understanding of the topic.

What is the difference between reliability and validity?

Reliability refers to the consistency of a measure or study. If the study were repeated, would the same results be found? Validity refers to the accuracy of a measure or study. Does it truly measure what it claims to measure? A measure can be reliable but not valid (e.g., a faulty weighing scale consistently shows you are 5kg too light), but it cannot be valid if it is not reliable (if the results are inconsistent, they cannot be accurate).