University of California
Type of paper: Thesis/Dissertation Chapter
Correlations measure the relationship between two variables. Establishing correlations allows researchers to make predictions that increase the knowledge base. Different methods that establish correlations are used in different situations. Each method has advantages and disadvantages that provide researchers information that is used to understand, rank, and visually illustrate how variables are related. The Pearson’s, Spearman, Kendall Rank, and positive and negative correlation are methods used to establish a correlation between variables. The Pearson method is a simple linear correlation used or illustrate how strong of a relationship two variables have. The Spearman method ranks data by order or name and is often used because the equation is simpler than Pearson’s. The Kendall Rank method measures the strength of dependence between two sets of random variables. Depending on the use of the information will determine the best method for the research project. Each method has advantages and disadvantages. The research project and individual researcher weigh out the positive and negatives in order to determine the best method. It is agreed that the Pearson’s method is easy to understand and illustrates the strength of the correlation. A prominent disadvantage is there can be confusion because it may be assumed that correlation establishes causation. The Spearman advantage is it can rank order or name data in various ways, depending on the data collected. The disadvantage discussed is there may be a focus on ranking and not on the information that creates the rank. The positive and negative correlation method has the advantage that a lot of variables and situations can be used. Variables can be studied using this method that experiments cannot be conducted on. The clear disadvantage discussed is that no cause and effect relationship can be assumed. Another discussed disadvantage of this method is that it does not account for other variables that may contribute to studied variables. Information reveals creating correlations in research using the Pearson method would be useful in domestic violence because it is a method that is easy to understand. The Spearman method that ranks data was discussed to be useful in the area of ranking of comfort qualities provided by hospice and GPA or SAT rankings. The Kendal Rank method measures strengths of dependence between two sets of variables like GPA and job performance in the degree field. Discussion about reading proficiency in children was an example that would utilize the positive and negative method the best.
As determined correlation determines the relationship between two variables and is used to make predictions in research. Each method has clear advantages and disadvantages, but it is agreed that the easier the method is to understand the more useful it is. One key point that causes confusion is the relationship between correlation and causation. It was determined that to avoid the error that a cause can be assumed based on a correlation attention must be paid to the specific method. Not every method is designed to illustrate cause and affect relationships.
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