A study has been undertaken to examine the effect of background music and assembly method on the productivity of workers on a production line for electronic circuit boards. Each of 8 workers has been randomly assigned to one of 4 cells, as shown here.
So that each worker will hear only the intended type of music, headphones are used for the background music in the experiment. Data are the number of circuit boards assembled in 1 hour.
Using the 0.05 level of significance in testing for the main and interactive effects, what conclusions should be drawn from this experiment? Determine the 95% confidence interval for the population mean for each factor level.
