In Case of bivariate population, we calculate the correlation coefficient by cross tabulation method, Charlie Spearman's coefficient and Karl Pearson Coefficient.
Cross tabulation is useful when given data are in nominal form. Under it we can classify each variable into two or more categories and then cross classify the variables in these sub categories.
In Symmetrical relationship is one in which the two variables are vary together, i.e. if one is increase or decrease other variable is also increase of decrease.
In case of Reciprocal relationship, when the two variables are mutually influence or reinforce to each other.
Asymmetrical relationship is exist if one variable (independent variable) is responsible for other variable (dependent variable).
Charlie Spearman's Rank Correlation Coefficient :
Karl Pearson Correlation Coefficient:
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