Question

1. Describe a scenario where the Pearson correlation would be appropriate to use in calculating the strength of the relationship between two variables. Identify the variables and explain the rationale for your answer.

2. Describe a scenario where the Spearman correlation would be appropriate to use in calculating the strength of the relationship between two variables. Identify the variables and explain the rationale for your answer. What makes this scenario different from the scenario in the previous question?

Answer 1

1. The Pearson correlation is the most widely used technique to calculate correlation. It is used when a linear relationship needs to be calculated between two variables. The variables in this case are continuous. For example, when the researcher wants to investigate the relationship between temperature and ice cream scales, the Pearson correlation would be appropriate. The two variables here are temperature and ice cream sales.

2. The Spearman correlation is a non parametric technique used when the variables to be measured are in the form of an ordinal, ratio or interval scale. For example, if a researcher wants to investigate the relationship between the level of education and starting salaries, this technique would be appropriate. Here, the level of education and starting salary are two variables. The major difference between the two techniques is the scales of measurement used. While Pearson uses the Nominal scale, the Spearman correlation uses ranked data (ordinal, interval or ratio scale).