Currently, keyboards have the keys configured in an arrangement referred to as “QWERTY” because of the placement of those particular letters on the second row from the top. Supposedly, that configuration was designed to slightly slow typing so that keys would not jam in typewriters commonly used in days of yore. The Dvorak keyboard configuration is claimed to be more efficient by arranging keys according to frequency of use. Listed below are difficulty ratings of typing different words on each of the two keyboards (based on data collected by the author). The data are paired according to the same word used on both keyboards, and higher numbers correspond to words that are more difficult to type. 

a. Use a 0.01 significance level to test the claim that word difficulty scores are higher with the QWERTY keyboard.

b. Construct the confidence interval that could be used for the hypothesis test described in part (a). What feature of the confidence interval leads to the same conclusion reached in part (a)?

Transcribed Image Text:

QWERTY Dvorak 5 6 6 3 3 1 00 10 7 4 3 5 2 2 2 10 0 5 5 1 8 4 2 0 5 3 4 5 2 0