Many furniture pieces are built with veneer, a thin layer of ?ne wood that is fastened to less expensive wood products underneath. Face checks are cracks that sometimes develop in the veneer. When face checks appear, the furniture needs to be reconstructed. Because this is a fairly expensive process, researchers seek ways to minimize the occurrence of face checks by controlling the manufacturing process. In one study, the type of adhesive used was one of the factors examined.27 Because of the way that the veneer is cut, it has two different sides, called loose and tight, either of which can face out. Here is a table giving the numbers of veneer panels with and without face checks for two different adhesives, PVA and UF. Separate columns are given for the loose side and the tight side.
Loose side Tight side Face checks Face checks
Adhesive No Yes No Yes
PVA 10 54 44 20
UF 21 43 37 27
Analyze the data. Write a summary of your results concerning the relationship between the adhesive and the occurrence of face checks. Be sure to include numerical and graphical summaries as well as the details of your signi?cance tests.
The same researchers dida similar study for dogs.29 The data are given in the following table:
(a) Analyze the data for the dogs and the cats separately. Be sure to include graphical and numerical summaries. Is there evidence to conclude that the source of the animal is related to whether or not the pet is brought to an animal shelter?
(b) Write a discussion comparing the results for the cats with those for the dogs.
(c) These data were collected using a telephone interview with pet owners in Mishawaka, Indiana. The animal shelter was run by the Humane Society of Saint Joseph County. The control group data were obtained by a random digit dialing telephone survey. Discuss how these facts relate to your interpretation of the results.