Question

10. An investigator determines the correlation coefficient between triglyceride levels and degree of atherosclerosis in sampled blood vessels to be +1.67. On the basis of this information, you would conclude that:

Triglyceride level is a good predictor of atherosclerosis.

High triglyceride levels cause atherosclerosis.

Atherosclerosis causes high levels of triglyceride.

The investigator has incorrectly determined the correlation coefficient.

Answer 1

Correlation coefficient is a measure of the linear correlation between two variables

We are given, An investigator determines the correlation coefficient between triglyceride levels and degree of atherosclerosis in sampled blood vessels to be +1.67

Here, triglyceride levels is independent variable and degree of atherosclerosis is dependent variable.

However, correlation coefficient can take a range of values from +1 to -1 and a value of 0 indicates that there is no association between the two variables

As +1.67 is not in the range of correlation coefficient (-1 to +1), we can conclude that

The investigator has incorrectly determined the correlation coefficient