STSCI 2150 Prelim 1
Oct 1, 2013
1. What is volunteer bias? Give an example. 
People who volunteer for a study are not representative of the general population. If a study
uses only volunteers, the results will be biased because a non-represen
The Analysis of Biological Data - Whitlock and Schluter
Solutions to practice problems
1. (a) Ordinal (b) Nominal (c) Nominal (d) Ordinal
2. (a) Observational (cats were observed to fall a given number of storiesthe researchers did not
a. The average Titanic passenger age is 31.2 years.
b. The youngest age of a Titanic passenger is 0.1667 years (0.17 years)
c. The oldest age of a passenger is 71 years.
d. There are 633 passengers in the data s
a. 188.0643 mg is the mean
b. 95% CI: (167.52, 208.60)
Its not really predictable based on the spread of the histogram. It seems as though 160180mg is the most frequent, but there are values for mg amounts ranging from 140-260.
b. The equation Y =.25+.95X. Or, in more general terms, Offspring length= .
c. Null Hypothesis: The slope of the regression of offspring telomere length by
father telomere length is zero
a. n=5, sd=5.
d. The estimate for n=5 was 2.24. N=16, the estimate was 1.28. N=25, the
esitamte was 1. They are close.
Null Hypothesis: Honeybees do not distingu
a. Mosaic plot on the left has separate colors identifying the Survived group
and the Dead group.
-Mosaic plot on the left has a numbered y-axis that notes frequency.
-Mosaic plot of the right has large