The Purpose of the Partial Correlation, Essay Example

The purpose of the partial correlation is to statistically control third variables. When trying to find the correlation between two different variables that the researcher is studying, the influence of the third variable needs to be removed, or “partialed out”. The third variable needs to be controlled. Therefore, the role of partial correlation is to prove that there is a correlation between the two variables, even if the third variable is unchanged. The main point a partial correlation proves is that the correlation between the two studied variables is independent of the third factor.

To measure the partial correlation, the researcher will determine the impact of the third variable on the correlation between the two studied variables. As an example, a researcher might be trying to determine the relationship between minority status and children’s academic achievement. In this case, social status, family structure, and parental education level can be all treated as third correlations, and need to be measured as partial correlations. The researcher will need to ensure that there is a strong and straightforward correlation between minority status and children’s academic achievement, independent of the social class and parental education. Therefore, the correlation between variable two (academic achievement) and the two partial correlations need to be measured and “partialed out”. If the impact of the two partial correlations is found to be high, it is recommended that the researcher changes the study design to one that covers multiple correlations. If the correlation between the examined two variables and the third variable is found to be non-significant, the partial correlation method can be applied. The impact of social and family status needs to be measured and taken into consideration during the analysis of results, and must be presented in the study.