Question

You have been asked to engage in one final project for the chain of department stores for which you have been working concerning the sales of a type of shirt that they carry. Specifically, this time you wish to study the nature of the relationship between the average daily number of hours the stores are open and monthly sales for the month you have been studying. You wish to utilize the average daily number of hours the stores are open as a variable designed to predict and explain sales of the item in this month. Data concerning these two variables of interest is collected from a random sample of stores throughout the chain of stores. This data is shown on the next page. Various questions will be asked and then need to be answered about the results you generate. These questions follow the presentation of the data. You should answer the questions posed in a memo that will accompany your results. Where appropriate, be sure to annotate the printouts you include as a part of the work you have accomplished. Data: Number of Hours Sales 14 348 12 355 9 325 10 401 22 455 20 398 18 288 17 350 13 380 19 438 18 386 23 430 19 320 20 489 11 354 22 480 17 420 19 456 9 289 15 376 13 337 11 306 a) Create a scatter diagram of this data. Before you proceed further, make some observations about the behavior of the data, if you are able, based solely upon this diagram. b) Find the regression coefficients and the regression equation for this data by using the method of least squares analysis. c) On a separate scatter diagram, plot the regression line. State any additional observations about the behavior of the data you can based upon this scatter diagram. d) Provide meanings for each of the regression coefficients. Be sure these meanings relate specifically to the problem you are studying e) Use your regression equation in to predict monthly sales for a store or stores that are open for a daily average of 15 hours. Do the same for a store or stores that are open for a daily average of 8 hours. Do you have any concerns with either of these predictions? State a reason or reasons for any concerns you might have with either or both predictions.

Answer 1