Assignment:
Identifying Correlation Errors. In Exercises, describe the error in the stated conclusion. (See the list of common errors included in this section.)
1. Given: There is a linear correlation between the number of cigarettes smoked each day and the pulse rate, so that more smoking is associated with a higher pulse rate. Conclusion: Smoking causes an increase in the pulse rate.
2. Given: There is a linear correlation between annual personal income and years of education. Conclusion: More education causes a person's income to rise.
3. Given: There is a linear correlation between state average commuting times and state average commuting costs. Conclusion: There is a linear correlation between individual commuting times and individual commuting costs.
4. Given: The linear correlation coefficient for the IQ test scores and head circumferences of test subjects is very close to 0. Conclusion: IQ scores and head circumferences are not related in any way.