General instructions for the content of all StatTools assignments and the use of StatTools:

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1 General instructions for the content of all StatTools assignments and the use of StatTools: An important part of Business Management 330 is learning how to conduct statistical analyses and to write text that describes the intent, results, and interpretation of the analysis. You will be using Excel and StatTools, a statistical software package that operates in the Excel environment, to assist you in obtaining appropriate statistical results. (You may use Minitab or other statistical program if you do not have access to StatTools.) On time submission of your assignments is important, just as is the on-time arrival of a part in a just-in-time manufacturing environment. Assignments are due at the beginning of class on the date indicated on your course schedule. Late assignments will not be accepted for any reason. You may NOT submit assignments electronically. You may NOT slide assignments under the office door. You may NOT place assignments in your instructor s mail box. Please do not ask to be treated differently than your peers. Each homework submission must include: 1. A cover page. Your instructor will dictate the requirements for the cover page. 2. Typed responses to all questions in order, or a summary written as a professional report, as dictated by the particular assignment instruction. Your grade depends not only on content, but also on construction. Your document should have a logical and easily recognizable order, have all components clearly labeled, use clear, well-formed sentences (or paragraphs where appropriate), clearly identify all references to StatTools results with labeling and annotation. To annotate, all values/information in the StatTools computer output referenced when answering the questions or writing your report must be highlighted, circled or otherwise clearly identified, both in the computer output and in the text. An example of the use of annotation in a response to a question is given below. Example Annotation Using Highlighting ANSWERS c) The confidence interval generated by StatTools to estimate the mean difference (µ D ) in heating cost using the paired t analysis follows: Conf. Intervals (Paired-Sample) Uninsulated - Insulated Sample Size 15 Sample Mean 57.4 Sample Std Dev Confidence Level 95.0% Degrees of Freedom 14 Lower Limit Upper Limit

2 d) We can be 95% sure that the mean difference in heating costs is a value between $50.12 and $ Since the interval is entirely positive (and, therefore, does not contain 0), it does allow the contractor to infer at the 5% significance level that the heating cost for insulated houses is less than that for un-insulated houses. With 95% confidence, the mean savings due to insulating the house is between $50.12 and $64.68 per time period. 3. The complete StatTools output generated in order to fulfill the requirements of the assignment, unless your instructor directs otherwise: Do not cut and paste pieces of the output from a procedure. Note in the example above that while only two numbers from the computer output from the Conf. Intervals (Paired- Sample) procedure in StatTools were used to answer the question, the entire section of results was copied and pasted into the solution document. Supporting information for graphs, such as bin information related to the construction of a histogram, does NOT need to be included. Do not include irrelevant analyses. For example, if you are not sure whether you should perform an analysis using the Two-sample procedure or the Paired-sample procedure, you must make a choice and include only one. Throwing lots of things at the wall, in hopes that something will stick, will harm your grade. Do not include printouts of the original data (individual observations) unless instructed to do so. You must annotate the StatTools output. (See instructions above.) Computer output should be labeled appropriately; Figure 1 or Table 1, for example. Graphs should be sized appropriately. If multiple graphs are required in an assignment, the graphs should be re-sized in order to reduce the number of pages in your report. The re-sized graph should maintain the original aspect ratio and be large enough that all detail can still be read. A report template may be provided for your use. If a template is provided, your instructor may require the use of this template, or your instructor may make the use of the template optional.

3 Accessing StatTools: Load/Open the StatTools Program. Option 1 Using the Fisher College of Business Labs: StatTools is already available in the Mason Hall Labs. To access the software, look for Palisades in the Programs list. StatTools is included as one of the products in the Palisades list. Double click on it to open it. Option 2 Purchase the one year student license of the DecisionTools Suite (which includes StatTools and 6 other tools) for $50 at the following link: After placement of your order, you will automatically be sent an installer and an activation code. Using StatTools for statistical analyses: 1. Access or create an Excel data file. 2. Declare the data as a StatTools data set: StatTools is referred to as an Excel Add-In, however it will not operate on Excel files directly. Every data file that you wish to perform analysis on using StatTools must be declared as a StatTools data set: Place the cursor somewhere inside the relevant data set and click. Select the Data Set Manager from the StatTools menu. Occasionally you will find that the declaration will work only if you highlight the entire data set. This will be true, for example, if the data set has empty columns or rows imbedded in it. StatTools > Data Set Manager It will then show you a dialogue box such as this asking you if the data highlighted is the correct data. Check to make sure that the specified range includes all of the data you want included, and then click Yes, or No as appropriate. The following box will appear.

4 Click OK Again, double check that all of the relevant data has been included. If not, you can manually change what is included by changing the Excel Range under the Data Set sub-category. Also, if your columns of data have labels, make sure that the Names in First Row box has been checked this will allow you label each column without it affecting the data within each (if this is not checked and you have labeled the columns, you will get an error message to that effect). Be sure to make a note of the name of your data set. StatTools will automatically assign the name Data Set #numeral, but you can change the data set names. The data set has now been declared as a StatTools data set, and you can operate on it with any of the StatTools functions/procedures. Remember, every data set must be declared in StatTools before you can manipulate it using StatTools procedures. 3. Select the desired StatTools procedure. Examples of the implementation of the StatTools procedures: Example 1: To determine how many beers to stock, the concession manager at Yankee Stadium wanted to know how the beer sales were related to outside temperature during the game. Accordingly, she took a sample of 10 games and recorded the number of beers sold and the temperature in the middle of the game. The data was typed into an Excel spreadsheet, and then declared as a StatTools data set using the steps outlined above: Temperature Beers 80 20, , , , , , , , , ,742

5 First, the concession manager might want basic summary information like means and standard deviations for the temperature and beer sales. In StatTools we use One-Variable Summary to obtain that information. StatTools > Summary Statistics > One-Variable Summary All procedures in StatTools will have a similar dialogue box to complete. You will need to identify the Data Set being used, the Format of that data set (stacked or unstacked click on the Format button for a menu), and the variables being used. Each procedure will have specific additional requirements. For the one-variable summary, we need to select the specific summary information we desire. Do this by checking the box next to any item desired (or unchecking boxes next to items not desired). When the dialogue box is completed, click on OK. Results: StatTools (Core Analysis Pack) Analysis: One Variable Summary Performed By: schroeder_1 Date: Tuesday, December 11, 2007 Updating: Live Temperature Beers One Variable Summary Data Set #1 Data Set #1 Mean Variance Std. Dev Count The average temperature for the 10 observed games was 80.5 degrees.

6 Beer Sales Beers / Data Set #1 Example 1- cont d: Suppose the concession manager would like to investigate the relationship between temperature and beer sales by looking at a scatter plot. We use Scatterplot in StatTools: StatTools > Summary Graphs > Scatterpolot Once again, be sure to identify the correct data set. For a scatter plot, we need to identify a variable to create the Y-axis and a variable to create the X-axis. Result: Figure 1 Scatterplot of Beers vs Temperature of Data Set # Temperature / Data Set #1 Figure 2 Scatterplot of Beer Sales vs Temperature Temperature You will note that the scatter plots in Figures 1 and 2 are for the same sample data, but the presentation in Figure 2 is much more appealing. You can edit the scatterplot created by StatTools using the options in Excel > Chart.

7 Example 2: The data in this example includes tips earned by servers at a restaurant as a percent of the food and beverage bill and the gender of the server. The values to be analyzed are the tips. All of these Values are stacked in one column, even though they are observed in two different groups. The groups are identified in the Gender column, and they Categorize the tips. Once again it has been declared a StatTools data set using the steps outlined above. Note that the Tips for both Genders have been Stacked in one column. Tips Gender 11 Male 12 Male 15 Male 11 Male 10 Male 12 Male 11 Female 12 Female 18 Female 15 Female 8 Female 15 Female We might be interested in comparing tips earned by male servers and female servers. Box-plots for the two groups would be informative. StatTools > Summary Graphs > Box-Whisper Plot Be sure to identify the data set being analyzed. The format must be specified as stacked. Click on the Format button and select Stacked in the menu. As a result, each variable can now be identified as a Val (values) variable or a Cat (categories) variable. Result: Figure 3 Box Plot of Comparison of Tips / Data Set #2 Gender = Male Gender = Female

8 Example 2 cont d: Some procedures will require that the data be in either Stacked or Unstacked form. For example, you can create scatter plots ONLY with data that is in unstacked form. You can easily change from one form to the other by using the Data Utilities option in StatTools. Let s unstack the tips data from the previous example. StatTools > Data Utilities > Unstack The Unstacking Utility will separate the one column of values into multiple columns. Each of the new columns will contain the values for one of the categories. You will need to instruct StatTools which variable (column) contains the values to be unstacked, and which variable (column) contains the list of categories. Results: Tips(Female) Tips(Male) You can find additional examples in the Sample Assignment Solution that is posted on the StatTools Resource page of the course web site. You can find a complete reference guide to the use of StatTools on the StatTools Resource page of the course web site.

9 Special symbols and equations: You will need to include special symbols in the text of your report/answer document on occasion. A learning objective of the course is differentiating between parameters and statistics. It is important to know when to refer to a parameter and when to refer to a statistic, it is therefore important for you know how to insert the proper text. In most cases you will use Greek symbols in your document when you are referring to population parameters. (The population proportion, p, is an exception.) There are two ways to insert Greek letters in MS Word. One is to insert a symbol (Insert > Symbol > scroll for the desired character and select it > Insert). The other is to use the equation editor (Insert > Object > Microsoft Equation Editor OR Tools > Customize > Commands > Insert > Equation Editor). When you wish to refer to a special statistic, e.g., X, the equation editor may be your only option. Be aware that switching computers (operating systems) may contaminate the equation. To create X with the equation editor: Office 2003 and XP Open equation editor: Type X in the vacant box: Select (click on) the over-strike menu: Click on the type of over-strike you want:

10 To exit the equation editor simply click your cursor anywhere outside of the equation editor box if you are using a PC. Office 2007, Vista (You must be working in a document that is saved as.docx. If you are not, Equation is not an active tool on the ribbon. In that case, you will only have editing capabilities for equations. You can copy and paste any equation into the document and edit it to suit your needs.) Insert > Equation To create x, click on Accent

11 Select the bar over-strike option Place your cursor inside the box and type x Click anywhere outside the equation box or hit Enter. I find the old equation editor much more user friendly, so I m inclined to paste an equation into my document and edit it. Additional instructions will be provided with each assignment to assist you with procedures being introduced in the assignment. You must be willing to experiment with any new software, though, to become proficient in its use.

12 Using the CD bundled with your text book: Note: Common short-hand notation when giving instructions for a sequence steps that must be taken to achieve a goal with your computer is to list the steps in order separated by the symbol >. For example, to open a new file in Microsoft Word, you could click on File, click on Open, and click on New. We can short-hand with the following: File > Open > New. Assignments may require you to access data stored on the disc that accompanies your text. Some instructors may post the data sets needed for the assignments on Carmen. Even so, you may want to hone your statistical skills by practicing with other data sets. Follow the steps below if you have difficulty accessing the data sets from the disc. 1. In Excel > File > Open 2. Go to Look In: and click on the down arrow to view access locations. Find PBS2e in the list and Open it (double click): 3. Find Data Sets and Open it

13 4. Select Excel 5. Choose the relevant chapter 7. Select the required data set You should now have the desired data in an Excel spreadsheet.