The research error described above is an example of selection bias.
Selection bias takes place when, from a population of interest, a group of individuals is selected in order to construct a sample but without a proper randomization. The result is a sample which is not representative of the underlying population.
According to the example, the target population of the research comprises all students but the sample only includes boys. Hence, selection has not been random because it followed a gender criteria, and the results obtained using it cannot be applicable to the whole population because they are affected by a selection bias.
Answer:
qualitative research
Explanation:
Richard, a research scholar, wanted to do a research study in a subject which does not have a lot of preexisting knowledge. SO he will have to ask basic question to his research subjects in order to get an overall idea about the topic. By doing such he will be able to gain a basic knowledge about the subject he had chosen.
Qualitative research is done to obtain or which aims at expanding and gaining knowledge by asking basic question research participants related to the subjects.
Thus the answer is qualitative research.