1. Pregnant women are encouraged to limit their caffeine consumption because caffeine is believed to cause low birth weight. A researcher collects data from a random sample of 50 new mothers at one large hospital. She surveys the mother about her caffeine consumption (in milligrams per week) and records the baby’s birth weight (in ounces).
A. What are the explanatory and response variables? Explain how you identified these.
B. Is caffeine consumption (in milligrams per week) a categorical or quantitative variable?
C. Is baby’s birth weight (in ounces) a categorical or quantitative variable?
D. Is this an observational or experimental study? Explain how you determined this.
E. If a negative relationship is observed, can the researcher conclude that higher caffeine consumptions causes lower birth weight? Explain why or why not.
F. What is one possible confounding variable in this study? Explain why this is a possible confounding variable.