SPSS Basic Skills Test (This document is available at http://www.psy.mq.edu.au/psystat/skillstest ) The following is a test of your ability to carry out a few basic procedures in SPSS. Everything that the test asks you to do is covered in the handbook Introduction to IBM SPSS Statistics (referred to here as Intro, and sometimes as "the red book", after the colour of its cover). If you haven't got a copy of Intro, you can download it from http://www.psy.mq.edu.au/psystat/documents/introspss.pdf Some people will be able to do the test without referring to the handbook; others will have to work through it, and refer to Appendix 7 in Intro, Examples of Data Manipulation. The aim of the test is to ensure that everyone who passes it has a basic knowledge of SPSS which will provide a foundation for further work. Read the instructions carefully, because if the output you submit does not meet the specified requirements exactly, you will have to repeat the parts you have not done properly. If what you send in has a lot of errors, you may have to carry out the whole test again, with a different dataset. Before you send the test, make sure that you check the section at the end of this document, which tells you how to avoid the most common errors errors which meant that students had to redo part or all of the test. Preparing for the Test 1. The first step is to make sure that the version of SPSS that you are using is set up appropriately. Go to Section 4 of Intro and set the options as described there. In particular, make sure that Display commands in the log is checked, so that the syntax (or the syntax-equivalent generated by the point-and-click commands) will be shown in the output that you send in (if the syntax is not shown in your output, you will automatically have to repeat the test). Also make sure that you set the Output Labels as described. 2. The next step is to obtain the dataset that you will use. Go to http://www.psy.mq.edu.au/psystat/skillstest and click on the appropriate link for your unit in the Data section of the page, then on the link that shows your student ID number. If you can't find your student ID number, email me at skills.test@mq.edu.au with your ID and unit code. Note that if you use the wrong dataset, you will have to repeat the test with the correct data. The data are contained in an Excel spreadsheet (one of the basic skills you will demonstrate is the ability to read data into SPSS from Excel). Depending on how your browser is set up, you will be asked whether you want to Open or Save the file. It's probably best to save the file rather than open it, but if you open it in the browser window, you can then save it to your computer. If you have any trouble with the file (such as the browser trying to display it without using Excel, which will result in a very
-2- messy look), you can always save it by clicking the right mouse button on the link and selecting Save Target As... (Internet Explorer), Save Link as (Chrome), Save Link Target As... (Netscape or Mozilla Firefox) or the equivalent in the browser you are using. Notes: 1. You may find that some browsers are configured in such a way as to prevent you downloading your spreadsheet as described above. You will need to find a browser which allows you to obtain your dataset. 2. If cannot find your ID number in the appropriate list, email skills.test@mq.edu.au and I will assign you a dataset to download. Make sure you give your ID number and your unit code in the email. The Dataset The data you will use are taken from a survey conducted by Dr Peter Langford, then of the Department of Psychology, at Macquarie University, Sydney, Australia, and his students. Dr Langford is now Director of Voice Project, a consultancy specialising in workplace surveys (www.voiceproject.com), and can be contacted on peter.langford@voiceproject.com. The respondents were employees of a number of organisations who answered questions about themselves and gave their opinions on a number of topics relating to their work and the way their organisation functioned. The full list of variables is given at http://www.psy.mq.edu.au/psystat/skillstest/orgvars.htm. In the skills test, you will be concerned with only a few of the variables. The Test 3. Read the dataset into SPSS, as described in Appendix 2 of Intro. Note that the variable names are given in the first row of the Excel spreadsheet and that these should be read into SPSS appropriately along with the data. (However, you do not have to specify the Range when opening the spreadsheet.) 4. Attach value labels to the gender variable (1=male, 2=female). 5. Produce a one-way frequency table of gender. At this point make sure that the output that you have produced contains the syntaxequivalent for reading the data into SPSS from Excel, and for the production of the frequency table, as well as the frequency table itself. If any of these things is missing, go back to 1., set the options correctly, and start again. You may use syntax or point-andclick methods to produce the output, but in either case either the syntax, or the point-and-click equivalent, must appear in the output.
-3-6. Use the recode command to produce a new variable called fulltime from the hours variable, which has a value of '1' for employees who work 35 or more hours per week and '0' for those who work fewer than 35 hours per week. 7. Produce a crosstabulation of gender and fulltime which shows the percentage of male and female employees who work full- and part-time (NOT the percentage of full- and part-time workers who are male or female make sure you show the correct percentages). 8. Use the correlations procedure to obtain the Pearson correlation of the variables q01and q02. 9. Edit the table of correlations obtained in 8. so that the correlation coefficients are shown to four decimal places. 10. Use the compute procedure with the mean function (see Pp 25-26 of Appendix 7 in Intro, which describes the method you must use) to produce a variable called manage which is the mean of the responses on the variables q01, q02, q03 and q04. 11. Use the means procedure (which is different from the mean function) to obtain the mean of the manage variable for male and for female employees. 12. Use an independent groups t-test to test whether the mean of the manage variable is different for members and non-members of unions (the variable union, where 1=member and 2=not a member). 13. Use the syntax manova manage by union(1,2)/design. to repeat the analysis carried out in 12. 14. Save the data file as org.sav. 15. Temporarily select only the employees who are married or in a de facto relationship (married, where 1=married or in a de facto relationship and 2=neither married nor in a de facto relationship) and obtain the mean number of children (children) for these employees. You may need to look in Appendix 7 of Intro to find the descriptives procedure which will provide the mean. You must use the descriptives procedure, not the means or frequencies procedure. Don't forget to turn off the selection of married respondents before attempting the remaining questions. 16. Obtain a histogram of the variable tenure (number of years with current employer). You may need to consult Appendix 8 of Intro to find how to do this with the frequencies procedure. Do not include the table in the output which you submit. 17. Obtain a scatterplot with the variable tenure (number of years with current employer) on the horizontal (x) axis and hours (hours worked per week) on the vertical (y) axis. 18. Use the GLM procedure to carry out a one-way analysis of variance (ANOVA) with overtime as the dependent variable and age (which, in this dataset, is a categorical
-4- variable) as the grouping variable (fixed factor). As part of the GLM analysis, ask for a plot which shows the mean of overtime for each age group. 19. Use Edit/Copy (or Copy Objects in earlier versions of SPSS) or File/Export to copy all the relevant output (including syntax, tables, graphs and text output) into Word (see Appendix 6 of Intro) and save the resulting Word document as yourstudentidnumber.doc (e.g., 86603702.doc). If you use the Export option, make sure that you specify All Visible under Objects to Export, NOT All. The All option can include unnecessary parts of the output which make the Word file very cluttered. You don't have to label the output to show which parts relate to each task, but DO make sure that the output is in the same order as the tasks listed above. If the output is hard to read because it isn't in the correct order, or because of extraneous material, you will be asked to modify the Word document and resubmit it. Sending the Output 20. Email the Word document as an attachment to me at skills.test@mq.edu.au. Put your surname, student ID number and unit code (e.g., Taylor 86603702 PSY 418) in the Subject field of the email. There is no need to include any information in the body of the email itself (I won't be put out if you don't greet me in the email!). Do not send the output to my address. If you do, I'll ask you to resend it to the correct address, skills.test@mq.edu.au. Note that if your email and the attached document do not meet the specifications given above, your email may be ignored and you will not have met the requirements of the Skills Test. Avoid Having to Repeat All or Part of the Test! Before sending your output, please check the advice given below, which is based on most common errors people have made, and which have led to them having to repeat all or part of the test. You will save yourself and me a lot of time if you can avoid these errors the first time you send in your output. Alan Taylor Department of Psychology Last updated on 6th of March, 2014
-5- Avoiding Common Errors (the numbers refer to the task numbers given on the previous pages) 3. Make sure that you include the syntax-equivalent of the point-and-click commands you use to read the data from Excel. They should look something like: GET TRANSLATE FILE='C:\skillstest\86603702.xls' /TYPE=XLS /MAP /FIELDNAMES. Data written to the working file. 69 variables and 100 cases written. Variable: PERS_ID Type: Number Format: F7 Variable: M_ORGPER Type: Number Format: F11.2 or GET DATA /TYPE=XLS /FILE='C:\My Documents\Basic Skills Test Data Set.xls' /SHEET=name 'Sheet1' /CELLRANGE=full /READNAMES=on. Make sure that the commands are the ones used to read that data from Excel, NOT from a text or SPSS data file. 6. Make sure that you haven't recoded 35 hours to zero. 7. Make sure you have included percentages in the table (not just the numbers of cases), and that they are the correct percentages. i.e., the percentage of male and of female employees who work full- or part-time (NOT the percentage of full or part-time employees who are male and female, or the percentage of all employees who are full-time or part-time). 9. Make sure you edit the table of correlations to show four decimal places. 10. Make sure you use the mean function. The syntax generated by you or SPSS should look like this: COMPUTE manage = MEAN(q01,q02,q03,q04). NOT like this: COMPUTE manage = (q01 + q02 + q03 + q04)/4. If you use the second syntax, you'll be asked to carry out this part of the test again. 15. Make sure you use Select Cases to select the appropriate cases (see the section on Omitting the Outlier from the Correlation Calculation in Intro). Do NOT use the means procedure to get separate means for married and unmarried employees. Make sure you use the descriptives procedure (AnalyseDescriptive StatisticsDescriptives) to get the mean number of children of the selected cases. Do NOT use the means or frequencies procedures. 16. Make sure you have included the histogram, and not the table.
-6-18. Make sure you use the GLM procedure (AnalyseGeneral Linear Model), NOT the Oneway ANOVA procedure. 19. Make sure that you send a Word document, not the SPSS output file. Also, make sure that the items in the file are in the same order as the tasks are listed above, and that there is no extraneous material in the file. One example of such unnecessary material is the SPSS Notes table, which looks like this: Don't include tables that look like the above! They are unhelpful clutter. Finally, make sure that you send the Word file to the correct address, skills.test@mq.edu.au.