Discussion:
Q: A student team examined parked cars in four different suburban shopping malls. One hundred vehicles were examined in each location. Research question: At alpha = .05, does vehicle type vary by mall location?
Vehicle Type...............Somerset........Oakland..........Great Lakes..........Jamestown.........Row Total
Car...................................44..................49....................36...........................64.................193
Minivan..............................21.................15....................18...........................13..................67
Full-sized Van....................2....................3......................3.............................2...................10
SU.....................................19..................27....................26...........................12..................84
Truck................................14...................6.....................17............................9....................46
Col Total..........................100................100.................100..........................100.................400
In all exercises, include MegaStat, Excel, or MINITAB exhibits to support your calculations.
State the hypotheses, show how the degrees of freedom are calculated, find the critical value of chi-square or from Excel's function =CHIINV (alpha, deg_freedom), and interpret the p-value.
Tell whether the conclusion is sensitive to the level of significance chosen, identify cells that contribute the most to the chi-square test statistic, and check for small expected frequencies. If necessary, you can calculate the p-value by using Excel's function =CHIDIST (test statistic, deg_freedom).