The dataset helium2 contains an experiment on helium filled footballs. This data is taken (with some reshaping by me) from the OpenIntro R package, which contains the following description: At the 1976 Pro Bowl, Ray Guy, a punter for the Oakland Raiders, punted a ball that hung mid- air long enough for officials to question whether the pigskin was filled with helium. The ball was found to be filled with air, but since then many have tossed around the idea that a helium-filled football would outdistance an air-filled one. Students at Ohio State University conducted an experiment to test this myth. They used two identical footballs, one air filled with air and one filled with helium. Each football was kicked 39 times and the two footballs were alternated with each kick. You can get the data using: load(url(\"http://stat511.cwick.co.nz/homeworks/helium2.rda\")) head(helium2) a) Make a plot to compare the distance of kicks between the air and helium filled footballs. Give a one sentence justification of the plot you chose. b) How do the helium filled footballs comapre to the air filled footballs? c) Why might the trial variable also be important? Solution http://www.stat.cmu.edu/~brian/S-Tutorial/_dataframes/node11.html.

1. The dataset helium2 contains an experiment on helium filled footballs. This data is taken (with
some reshaping by me) from the OpenIntro R package, which contains the following description:
At the 1976 Pro Bowl, Ray Guy, a punter for the Oakland Raiders, punted a ball that hung mid-
air long enough for officials to question whether the pigskin was filled with helium. The ball was
found to be filled with air, but since then many have tossed around the idea that a helium-filled
football would outdistance an air-filled one. Students at Ohio State University conducted an
experiment to test this myth. They used two identical footballs, one air filled with air and one
filled with helium. Each football was kicked 39 times and the two footballs were alternated with
each kick. You can get the data using:
load(url("http://stat511.cwick.co.nz/homeworks/helium2.rda")) head(helium2) a) Make a plot
to compare the distance of kicks between the air and helium filled footballs. Give a one sentence
justification of the plot you chose. b) How do the helium filled footballs comapre to the air
filled footballs? c) Why might the trial variable also be important?
Solution
http://www.stat.cmu.edu/~brian/S-Tutorial/_dataframes/node11.html