1. Discuss the strengths and weaknesses of correlational and regression studies; discuss concepts such as positive and negative correlations, correlation coefficients, confounding, and causality.
2. You read an interesting study in the paper that says that during any given year, statistics show that ice cream consumption and the crime rate are correlated - as ice cream consumption rises, the crime rate rises; as ice cream consumption drops, so does the crime rate. Explain this spurious correlation.
1. Correlation analysis measures the linear association between variables. The correlation coefficient values are always between -1 and +1. A correlation coefficient of -1 means the variables are perfectly inversely related, a score of 0 indicates there is no linear relationship between the variables, and a score of +1 means the variables are perfectly related. There is also the possibility of confounding variables with correlation analysis that could make it look like there is a linear relationship that is not really true. An example of a possible confounding variable is water usage and baseball cap sales. More water ...