11.8 The paper “If It’s Hard to Read, It’s Hard to Do” (Psychological Science [2008]: 986–988) described an interesting study of how people perceive the effort required to do certain tasks. Each of 20 students was randomly assigned to one of two groups. One group was given instructions for an exercise routine that were printed in an easy-to-read font ( ). The other group received the same set of instructions, but printed in a font that is considered difficult to read ( ).
After reading the instructions, subjects estimated the time (in minutes) they thought it would take to complete the exercise routine. Summary statistics are given below.
Easy font Difficult font n 10 10 x 8.23 15.10 s 5.61 9.28 The authors of the paper used these data to carry out a two-sample t test, and concluded that at the .10 significance level, there was convincing evidence that the mean estimated time to complete the exercise routine was less when the instructions were printed in an easy-to-read font than when printed in a difficult-to-read font. Discuss the appropriateness of using a two-sample t test in this situation.