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Suppose the diets were in increasing order of cost (diet 1 is the CHEAPEST and diet 4 is the most expensive).  Which diet would you choose if you goal is to reduce coagulation time at a cost effective rate.

The data for this problem are courtesy of David Jarjoura of OSU. Consider an experiment in which 24 animals are randomly assigned to 4 different diets. At the conclusion of the study, the coagulation time (in seconds) for blood drawn from the animals was recorded. The results of the oneway ANOVA are shown below to compare the mean coagulation time by diet.  

5 randomly selected patients are sent to a clinic for two appointments.  The patients meet their clinician prior to the procedure and are then asked a series of questions to measure their anxiety level on a scale from 0-10.  Unbeknownst to them, there are 2 clinicians (one for each appointment with the order randomize).  A signed rank test is to be run to determine if their is a difference in the anxiety level across the clinicians.  Find the test statistic.  There are 2 acceptable answers. Note: there is clearly not sufficient power with only 5 patients but I wanted the calculations to be simple. Clinician 1 Anxiety Clinician 2 Anxiety 10 8 3 4 5 9 8 5 2 1  

The p-value report by the software was 0.1615. What is the best conclusion?

There [is1] a significant difference in the mean temperatures among the nine medications. There [is2] a significant difference in the mean temperatures among the three severities. Use alpha = 0.05 for all conclusions.

Are the differences in mean temperature for the nine medications the same for the three severities (i.e., is there NO significant interaction at the 0.05 significance level)?

Why is it best to treat this as paired data? 

How does the interaction plot confirm your answer to the previous problem?

The War in Afghanistan began _________________but, ______________________

A local health authority has expressed concern that general health practitioners are prepared to work for the government health service on qualification, but choose private practice once they have gained some professional experience. If this were to be the case then dentists in private practice would on average have longer experience than dentists working for the government health service.  For a town within this health authority, the 9 dentists working for the government health service and 11 dentists in private practice were asked how many years they had been in practice since qualification. None of the dentists carried out both health service and private practice work.     What is the appropriate analysis?