Return to the information in Practice Exercise 2. The researchers decide to treat verb type as if it were a quantitative factor with values ranging from 1 to 5. They fit a regression model with independent variables AGE(0 or 1), VERBTYPE, AGEVERBTYPE. This model had SSE = 448.67 with df = 56. Conduct a lack of fit test to compare this model to the full factorial model.

Data in Practice Exercise 2

Thirty participants aged 20 to 29 and 30 participants aged 40 to 49 are randomly assigned to one of five groups. Each group is given a list of words to recall. The lists vary in type from 1 = “most passive verbs” to 5 = “most active verbs.” The response variable is how many words can be recalled after 2 minutes. The data are given in Table 9.21.

Table 9.21 Data for practice exercise 2: words recalled. Verb Type 1 2 3 4 5 Age 20-29 11 10 16 12 13 14 64 8 11 11 16 16 16 16 15 13 12 14 9 12 9 10 11 11 11 10 Age 40-49 5 69699 59268 in 7 12 15 9 8 11 288 12 14 11 14 14 18 26 20 17 17 20 13 14 14 18 8 15 15