it Get started with Information Technology Services SPSS 12 Introduction SPSS is a comprehensive package for the statistical analysis of data which allows easy input and validation of the data Statistical techniques available range from the very simple to the very sophisticated Windows SPSS has been the market leader among statistical packages for Windows since it first appeared and is very widely used It can take data from most types of file and use it to generate tabulated reports, charts and plots of distributions and trends, descriptive statistics and complex statistical analyses This document describes the standard network version of SPSS 12.0 on the LSE network A basic understanding of statistics is a pre-requisite for the successful use of SPSS 12.0 Tutorials and further documentation SPSS for Windows is relatively easy to use, although even experienced users of SPSS/PC will find that they need to spend some time adjusting to the very different environment SPSS 12.0 does not come with a set of printed manuals However, SPSS tutorials to intermediate level are available on the LSE network The computer-based training tutorial provides an introduction to SPSS It can be accessed through the LSE website at ittraining.lse.ac.uk/specialistsoftware.html and is also available to buy on CD from the IT Help Desk SPSS 12.0 includes a comprehensive tutorial to intermediate level, which can be accessed through the Help menu in SPSS 12.0 It is also available at www.ittraining.lse.ac.uk/specialistsoftware.html Other SPSS resources can be obtained from this site The Library provides several copies of SPSS manuals for more detailed information on statistical procedures and syntax, for example The manuals may relate to previous versions of the software but the contents are nevertheless valid for SPSS 12.0 Help and advice Advice and general help on SPSS can be obtained from the IT Help Desk in on the Library Lower Ground Floor during the advertised opening hours Getting going To start SPSS 12.0, simply double-click on the SPSS icon on the desktop Alternatively, you can start SPSS as follows: On the Taskbar, click the Start button In the Start menu, choose Programs Then in the Programs menu, choose Statistics © London School of Economics and Political Science (August 2004) Document No 594 SPSS 12 Get started with In the Statistics menu, click on SPSS 12.0 for Windows The screen should clear and the SPSS for Windows initial screen will be displayed Existing SPSS files and databases can be opened from the dialog box or, alternately, click on the Cancel button to enter the data editor The SPSS Window has a menu bar from which you select SPSS operations such as opening files, choosing statistical procedures etc During your SPSS session, you may find it useful to look at the Status Bar at the bottom of the window which indicates the current state of the SPSS processor SPSS windows There are six types of window in SPSS: Data Editor: This window displays the contents of the data file You can create new data files or modify existing ones with the Data Editor Output Viewer: All statistical results, tables and charts are displayed in the Output Viewer You can edit the output and save it for later use Pivot Table Editor: Output displayed in pivot tables can be modified in many ways with the Pivot Table Editor You can edit text, swap data in rows and columns, add colour, create multidimensional tables, and selectively hide and show results Chart Editor: You can modify high-resolution charts and plots in chart windows Text Output Editor: Text output not displayed in pivot tables can be modified with the Text Output Editor Syntax Editor: You can paste your dialog box choices into a syntax window, where your selections appear in the form of command syntax The menus SPSS for Windows is menu driven Most of the features are accessed by making selections from the menus in the Application Window The main menu bar contains nine menus: FILE The File menu is used to open new and existing files and to save to a file These files can contain data in several different formats (eg raw data in an Document No 594 Get started with SPSS 12 ASCII file, data in a spreadsheet or a database file, or data saved from a previous SPSS job) or a description of the data or SPSS processing instructions EDIT The Edit menu is used to cut, copy and paste text from the output or syntax windows and to define and customise aspects of SPSS 12.0 (for example, currency) VIEW The View menu lets you choose whether or not to display the Status Bar, Toolbar and Grid lines It also has a facility for changing fonts DATA The Data menu affects the contents of the Data Editor Window and can be used to correct, select, weight or sort data; and to merge or split data files TRANSFORM The Transform menu is used to manipulate data or to create new variables as functions of existing ones ANALYSE All the statistical procedures can be found, grouped under logical headings, in the Statistics menu GRAPHS The Graphs menu is used to obtain the various forms of graphical representation of data such as charts, histograms and plots UTILITIES The Utilities menu contains some useful tools such as an index of commands with brief descriptions; information on the current variables; information on files available and a facility for changing fonts WINDOW The Window menu allows you to switch between the different windows and control their arrangement on the screen HELP The Help menu is comprehensive and well worth exploring as an early step in familiarising yourself with SPSS for Windows It has two useful options, Topics and Tutorial Help SPSS has a comprehensive, context sensitive, interactive help facility To obtain help on specific topics: Document No 594 From the Help menu, choose Topics The Help Topics: SPSS for Windows dialog is displayed SPSS 12 Get started with Click on the topic you would like to know more about then click Open When you have finished with Topics, click the Close box in the top right corner of the dialog box HELP WITH STATISTICS AND RESULTS OF ANALYSIS SPSS 12.0 also provides a statistics coach and a results coach to help you with your analysis The statistics coach can be found under the Help menu in the data editor window The results coach can be obtained by right-clicking on a table in the output viewer and selecting Results Coach Entering data and data descriptions Note: Whenever entering data, bear in mind that in SPSS the columns are the variables and the rows the cases You can enter data into SPSS in three ways ENTERING THE DATA INTERACTIVELY: Click on the title bar of the window labelled "Newdata" Click on the cell at the top left corner of the window At the bottom of the data window, select the “Variable View” sheet tab to define variables/labels/missing values, etc Type in the data, one item per cell, pressing the → key at the end of each item SPSS will automatically move the pointer to the next column To start another row, click on the first cell in that row in the first column IF THE DATA IS ALREADY IN A FILE THAT WAS PRODUCED BY SPSS: From the File menu, choose Open and then choose the Data option The Open Data File dialog box should appear From the list in the “File Type” box, select the correct file type Select the appropriate file by clicking on its file name after changing drives and directories if necessary Document No 594 Get started with SPSS 12 Click on the OK button The data will then be displayed on the screen in a Data Editor Window IF THE DATA IS IN A TEXT FILE (ALSO KNOWN AS AN ASCII TEXT FILE): From the File menu, choose the Read Text Data option A dialog box is displayed Select the appropriate file by clicking on its file name after changing drives and directories if necessary In the text import wizard, click on the Fixed button if the data for every variable is in the same column location on every line for every case in the data file Otherwise click on the Delimited button Follow the wizard to define the data and import into SPSS 12.0 The data will then be displayed on the screen in the Data Editor Window Editing data and data descriptions To change the names and data type of variables, select the “variable view” sheet tab at the bottom of the data window Double-click on a cell to edit the content An example of the variable view appears below Analysing the data From the Analyse menu choose the type of analysis you require, such as ANOVA, correlation or regression Note that simple analyses such as frequencies and cross-tabulation appear in the Descriptive Statistics option When you have selected the type of analysis, a dialog box will appear for you to enter the variable names to be included in the analysis All the available variable names appear in a list box To include one variable name off the list, click the variable name in the box and then click on the button To include more than one variable, click on the first name, hold down the CTRL key and click on all the other names for inclusion, finally clicking the button Document No 594 SPSS 12 Get started with In most analyses you will then be required to enter statistical or display options specific to the analysis to be performed These options appear directly in the dialog box or through option boxes which can be opened by clicking on them When all is complete click on the OK button to run the analysis Examining the results The results of the analysis appear in the Output Viewer They are available at any time in the SPSS session and can be edited and saved in a file for later use The Pause/scroll icon on the Toolbar can be used to halt the scrolling of output as it is generated The default mode is to have the output scroll continuously Saving and retrieving your work Save and retrieve your data files using the File menu When saving work remember to make sure that you have the correct drive and directory selected This should normally be your H: space Select your H: space by clicking on h: in the Drives box of the Save Data As dialog box Your results in the output window can also be saved to file, again by using the File menu Ensure that the correct drive and directory are selected before you click on the OK button Leaving SPSS TO EXIT FROM SPSS : • Choose Exit from the File menu; or • click on the Close box in the top right corner of the SPSS screen; or • press ALT+F4 while the SPSS window is active Document No 594 .. .SPSS 12 Get started with In the Statistics menu, click on SPSS 12. 0 for Windows The screen should clear and the SPSS for Windows initial screen will be displayed Existing SPSS files... Document No 594 Get started with SPSS 12 ASCII file, data in a spreadsheet or a database file, or data saved from a previous SPSS job) or a description of the data or SPSS processing instructions... OK button Leaving SPSS TO EXIT FROM SPSS : • Choose Exit from the File menu; or • click on the Close box in the top right corner of the SPSS screen; or • press ALT+F4 while the SPSS window is active