A magazine publisher is studying the influence of type style and darkness on the readability of her publica- tion. Each of 12 persons has been randomly assigned to one of the cells in the experiment, and the data are the number of seconds each person requires to read a brief test item. For these data, use the 0.05 level of significance in drawing conclusions about the main and interactive effects in the experiment. Determine the 95% confidence interval for the population mean for each factor level.
|
103.1
|
111.6
|
109.0
|
118.0
|
(Use data fileXR12099.)
|
|
|
108.9
|
117.8
|
111.8
|
115.8
|
|
Type Darkness
|
106.7 109.8 113.0 114.2
114.3 110.1 109.7 117.3
113.3 118.3 108.6 113.8
110.5 116.7 114.7 110.6