Question 14.45

14.45 Winery websites.

As part of a study of British Columbia wineries, each of the 193 wineries were classified into one of three categories based on their website features. The Presence stage just had information about the winery. The Portals stage included order placement and online feedback. The Transactions Integration stage included direct payment or payment through a third party online. The researchers then compared the number of market integration features of each winery (for example, in-house touring, a wine shop, a restaurant, in-house wine tasting, gift shop, and so on). Here are the results:8

Stage
Presence 55 3.15 2.264
Portals 77 4.75 2.097
Transactions 61 4.62 2.346
  1. Plot the means versus the stage of website. Does there appear to be a difference in the average number of market integration features?
  2. Is this an observational study or an experiment? Explain your answer.
  3. Is it reasonable to assume the variances are equal? Justify your reasoning.
  4. The data are counts (integer values). Also, based on the means and standard deviations, the distributions are skewed (can’t have a negative count). Do you think this lack of Normality poses a problem for ANOVA? Explain your answer.
  5. The statistic for these data is 9.594. Give the degrees of freedom and -value. What do you conclude?

14.45

(a) The Portals and Transactions stages seem to have higher integration features than the Presence stage. (b) An observational study. They are not imposing a treatment on the winery. (c) Yes, the largest is less than twice the smallest ; . (d) This shouldn’t be a problem because our inference is based on sample means, which will be approximately Normal given the sample sizes. (e) . There are significant differences in the number of market integration features of the wineries among those with different website stages.