Question

The research question or purpose of the study guides decisions about the research sampling. How might researchers ensure that they select a sample relevant to the research without introducing a bias?

To support your work, use your course and textbook readings and also use the South University Online Library. As in all assignments, cite your sources in your work and provide references for the citations in APA format.

Your initial posting should be addressed at 150-300 words. Submit your document to this Discussion Area by the due date assigned. Be sure to cite your sources using APA format.

Answer 1

Answer.

In research, sampling bias is a bias in which a sample is collected in such a way that some members of the population are less likely to be included than others. However, during the Interpretation phase the results can be erroneously attributed to the phenomenon under study rather than to the method of sampling (Panzeri et al. 2008), In order to reduce the effect of sampling bias, researchers use techniques such as:

Random sampling - avoid judgment or convenience sampling, researchers use random sampling where every element of the population has an equal chance of being a part of the sample.

Cluster sampling- this is a sampling method which involves dividing the population into various segments ad sub-sets such a small states into districts, districts into neighbourhoods, neighbourhoods into blocks, etc. where each segment is called a cluster and then a random sample is drawn from each of the cluster thereby resulting in a final sample which is diverse enough to account for the diferences in the population.

(ii) matching the participants in a sample based on certain common characteristics across the different treatment conditions such as same age, sex, motivation level, IQ etc is another method by which researchers try to minimise sampling bias and this helps to ensure that the final results are actually due to the independent variable rather than the intervening effect of the researchers’ method of selecting the participants( Rubin, 1973).

References:

Panzeri, S. et al. (2008), Scholarpedia, 3(9):4258. doi:10.4249/scholarpedia.4258

Retrieved on July 4, 2018:

http://www.scholarpedia.org/article/Sampling_bias

Rubin, D.B. (March,1973). ‘Matching to Remove Bias in Observational Studies’.Biometrics Vol. 29, No. 1 (Mar., 1973), pp. 159-183.