STATS 13 Study Guide - Final Guide: Statistical Significance, Heteroscedasticity, Simple Random Sample
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Final exam practice fall 2017: suppose a researcher is trying to predict how long americans live (y) based on their adult height (x). She takes a simple random sample of 200 americans and observes them until their death, and finds their mean height is 66 inches with a standard deviation of 4 inches. She finds their mean age at death is 82 years with a sd of 13 yrs. The sample correlation between height and weight is. Perhaps those with poorer diet are more likely to be smaller and also more likely to die younger. Thus the diet is the cause, not height: no, this would be extrapolation. [ (1-r2)] sy = 13 (1-. 22) = 12. 7 years. r2 = 0. 04: suppose a group of 100 bald men, 200 men with short hair, and 300 men with long hair are sampled and their pulses are measured.
