Manuale d’uso / di manutenzione del prodotto SPSS 22 del fabbricante IBM
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IBM SPSS Statistics 22 Brief Guide .
Note Before using this information and the product it supports, read the information in “Notices” on page 87. Product Information This edition applies to version 22, release 0, modification 0 of IBM SPSS Statistics and to all subsequent releases and modifications until otherwise indicated in new editions.
Contents Chapter 1. Introduction ........ 1 Sample Files .............. 1 Opening a Data File ............ 1 Running an Analysis ........... 3 Creating Charts ............. 4 Chapter 2. Reading Data ........ 7 Basic Structure of IBM SPSS Statistics Data Files .
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Chapter 1. Introduction This guide will show you how to use many of the available features. It is designed to provide a step-by-step, hands-on guide. All of the files shown in the examples are installed with the application so that you can follow along, performing the same analyses and obtaining the same results shown here.
The data file is displayed in the Data Editor . In Data V iew , if you put the mouse cursor on a variable name (the column headings), a more descriptive variable label is displayed (if a label has been defined for that variable). By default, the actual data values are displayed.
Running an Analysis If you have any add-on options, the Analyze menu contains a list of reporting and statistical analysis categories. W e will start by creating a simple frequency table (table of counts). This example r equires the Statistics Base option.
3. Click Income category in thousands [inccat] in the source list and drag it to the target list. 4. Click OK to run the procedure. Results are displayed in the V iewer window . Creating Charts Although some statistical procedur es can create charts, you can also use the Graphs menu to create charts.
2. Click the Gallery tab (if it is not selected). 3. Click Bar (if it is not selected). 4. Drag the Clustered Bar icon onto the canvas, which is the large area above the Gallery . 5. Scroll down the V ariables list, right-click Wir eless service [wireless] , and then choose Nominal as its measurement level.
The bar chart is displayed in the V iewer . The chart shows that people with wireless phone service are far more likely to have PDAs than people without wireless service. Y ou can edit charts and tables by double-clicking them in the contents pane of the V iewer window , and you can copy and paste your results into other applications.
Chapter 2. Reading Data Data can be entered directly , or it can be imported from a number of dif ferent sources. The processes for reading data stored in IBM SPSS Statistics data files; spreadsheet applications, such as Microsoft Excel; database applications, such as Microsoft Access; and text files are all discussed in this chapter .
Reading Data from Spreadsheets Rather than typing all of your data directly into the Data Editor , you can r ead data from applications such as Microsoft Excel. Y ou can also read column headings as variable names. 1. From the menus choose: File > Open > Data.
Reading Data from a Database Data from database sour ces are easily imported using the Database W izard. Any database that uses ODBC (Open Database Connectivity) drivers can be read directly after the drivers are installed. ODBC drivers for many database formats are supplied on the installation CD.
2. Select MS Access Database from the list of data sources and click Next . Note : Depending on your installation, you may also see a list of OLEDB data sources on the left side of the wizard (W indows operating systems only), but this example uses the list of ODBC data sources displayed on the right side.
6. Drag the entire demo table to the Retrieve Fields In This Order list. 7. Click Next . In the next step, you can select which records (cases) to import. If you do not want to import all cases, you can import a subset of cases (for example, males older than 30), or you can import a random sample of cases from the data source.
9. Click the Recode to Numeric cell in the Gender field. This option converts string variables to integer variables and retains the original value as the value label for the new variable. 10. Click Next to continue. The SQL statement created from your selections in the Database W izard appears in the Results step.
The T ext Import W izard guides you through the process of defining how the specified text file should be interpreted. 4. In Step 1, you can choose a predefined format or create a new format in the wizard. Select No to indicate that a new format should be created.
14. Select Dollar from the Data format drop-down list. 15. Click Next to continue. 16. Leave the default selections in the last step, and click Finish to import the data.
Chapter 3. Using the Data Editor The Data Editor displays the contents of the active data file. The information in the Data Editor consists of variables and cases. v In Data V iew , columns repr esent variables, and rows repr esent cases (observations).
The names that you entered in V ariable V iew are now the headings for the first three columns in Data V iew . Begin entering data in the first row , starting at the first column. 6. In the age column, type 55 . 7. In the marital column, type 1 . 8. In the income column, type 72000 .
Defining Data In addition to defining data types, you can also define descriptive variable labels and value labels for variable names and data values. These descriptive labels are used in statistical reports and charts. Adding V ariable Labels Labels are meant to provide descriptions of variables.
Changing V ariable T ype and Format The T ype column displays the current data type for each variable. The most common data types are numeric and string, but many other formats are supported. In the current data file, the income variable is defined as a numeric type.
Adding V alue Labels V alue labels pr ovide a method for mapping your variable values to a string label. In this example, there are two acceptable values for the marital variable. A value of 0 means that the subject is single, and a value of 1 means that he or she is married.
The reason a value is missing may be important to your analysis. For example, you may find it useful to distinguish between those respondents who refused to answer a question and those respondents who didn't answer a question because it was not applicable.
7. T ype NR in the V alue field. 8. T ype No Response in the Label field. 9. Click Add to add this label to your project. 10. Click OK to save your changes and return to the Data Editor .
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Chapter 4. Examining Summary Statistics for Individual V ariables This section discusses simple summary measures and how the level of measurement of a variable influences the types of statistics that should be used. W e will use the data file demo.sav .
3. Click OK to run the procedur e. The frequency tables ar e displayed in the V iewer window . The frequency tables reveal that only 20.4% of the people own PDAs, but almost everybody owns a TV (99.
2. Click Charts . 3. Select Bar charts and then click Continue . 4. Click OK in the main dialog box to run the procedur e. In addition to the frequency tables, the same information is now displayed in the form of bar charts, making it easy to see that most people do not own PDAs but almost everyone owns a TV .
8. Click OK to run the procedur e. The Frequencies Statistics table is displayed in the V iewer window . In this example, there is a large differ ence between the mean and the median. The mean is almost 25,000 greater than the median, indicating that the values are not normally distributed.
The majority of cases are clustered at the lower end of the scale, with most falling below 100,000. There are, however , a few cases in the 500,000 range and beyond (too few to even be visible without modifying the histogram).
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Chapter 5. Creating and editing charts Y ou can cr eate and edit a wide variety of chart types. In this chapter , we will create and edit bar charts. Y ou can apply the principles to any chart type.
The Gallery includes many different predefined charts, which ar e organized by chart type. The Basic Elements tab also provides basic elements (such as axes and graphic elements) for creating charts from scratch, but it's easier to use the Gallery .
measurement level. Instead of going back and changing the measurement level in the V ariable V iew , you can change the measurement level temporarily in the Chart Builder .
categorical (ordinal is a type of categorical measurement level), the y axis drop zone defaults to the Mean statistic. These are the variables and statistics you want, so there is no need to change the element properties. Adding text Y ou can also add titles and footnotes to the chart.
The bar chart reveals that respondents who are mor e satisfied with their jobs tend to have higher household incomes. Figure 34. Bar chart Chapter 5. Creating and editing charts 33.
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Chapter 6. W orking with Output The results from running a statistical procedur e are displayed in the V iewer . The output produced can be statistical tables, charts, graphs, or text, depending on the choices you make when you run the procedure. This section uses the files viewertut.
6. Drag the selected items to a new location in the outline. Y ou can also move output items by clicking and dragging them in the contents pane. Using the Pivot T able Editor The results from most statistical procedur es are displayed in pivot tables .
Pivoting T ables The default tables produced may not display information as neatly or as clearly as you would like. W ith pivot tables, you can transpose rows and columns ("flip" the table), adjust the order of data in a table, and modify the table in many other ways.
3. Drag the Statistics element from the Row dimension to the Column dimension, below Gender . The table is immediately reconfigur ed to reflect your changes. The order of the elements in the pivoting tray reflects the order of the elements in the table.
T o display a differ ent layer , select a category from the drop-down list in the table. Editing T ables Unless you've taken the time to create a custom T ableLook, pivot tables are created with standard formatting. Y ou can change the formatting of any text within a table.
Hiding Rows and Columns Some of the data displayed in a table may not be useful or it may unnecessarily complicate the table. Fortunately , you can hide entire rows and columns without losing any data. 1. If it's not already activated, double-click the Education Level table to activate it.
Y ou can also change the data type and format in this dialog box. 7. Select the type that you want fr om the Category list, and then select the format for that type in the Format list. 8. Click OK or Apply to apply your changes. The decimals are now hidden in the Percent column.
Using Predefined Formats 1. Double-click the Marital status table. 2. From the menus choose: Format > T ableLooks... The T ableLooks dialog box lists a variety of predefined styles. Select a style from the list to preview it in the Sample window on the right.
The formatting options include font name, font size, style, and color . Additional options include alignment, text and background colors, and margin sizes. The Sample window on the right provides a preview of how the formatting changes af fect your table.
8. Click OK to return to the T ableLooks dialog box. Y ou can save your new style, which allows you to apply it to future tables easily . 9. Click Save As . 10. Navigate to the target directory and enter a name for your new style in the File Name text box.
Changing the Default T able Formats Although you can change the format of a table after it has been created, it may be more efficient to change the default T ableLook so that you do not have to change the format every time you create a table. T o change the default T ableLook style for your pivot tables, from the menus choose: Edit > Options.
Edit > Options... 2. Click the V iewer tab. The settings are applied on an object-by-object basis. For example, you can customize the way charts are displayed without making any changes to the way tables are displayed. Simply select the object that you want to customize, and make the changes.
Y ou can specify differ ent settings for the outline and contents panes. For example, to show labels in the outline and variable names and data values in the contents: 3. In the Pivot T able Labeling group, select Names from the V ariables in Labels drop-down list to show variable names instead of labels.
Pasting Results as Word T ables Y ou can paste pivot tables into W ord as native W ord tables. All table attributes, such as font sizes and colors, are retained. Because the table is pasted in the W ord table format, you can edit it in W ord just like any other table.
Each column of the table is separated by tabs. Y ou can change the column widths by adjusting the tab stops in your word processing application. Exporting Results to Microsoft W ord, PowerPoint, and Excel Files Y ou can export results to a Microsoft W or d , PowerPoint, or Excel file.
2. In the Objects to Export group, select All . 3. From the T ype drop-down list select W ord/R TF file (*.doc) . 4. Click OK to generate the W ord file. When you open the resulting file in W ord, you can see how the results are exported. Notes, which are not visible objects, appear in W ord because you chose to export all objects.
Charts are included in the W ord document as graphic images. T ext output is displayed in the same font used for the text object in the V iewer . For proper alignment, text output should use a fixed-pitch (monospaced) font. Figure 56. Pivot tables in Word Figure 57.
If you export to a PowerPoint file, each exported item is placed on a separate slide. Pivot tables exported to PowerPoint become W ord tables, with all of the formatting of the original pivot table, including fonts, colors, borders, and so on. Charts selected for export to PowerPoint are embedded in the PowerPoint file.
Note : Export to PowerPoint is available only on W indows operating systems and is not available with the Student V ersion. If you export to an Excel file, results are exported differ ently . Pivot table rows, columns, and cells become Excel rows, columns, and cells.
Each line in the text output is a row in the Excel file, with the entire contents of the line contained in a single cell. Exporting Results to PDF Y ou can export all or selected items in the V iewer to a PDF (portable document format) file.
v The outline pane of the V iewer document is converted to bookmarks in the PDF file for easy navigation. v Page size, orientation, margins, content and display of page headers and footers, and printed chart size in PDF documents are controlled by page setup options (File menu, Page Setup in the V iewer window).
Exporting Results to HTML Y ou can also export results to HTML (hypertext markup language). When saving as HTML, all non-graphic output is exported into a single HTML file. When you export to HTML, charts can be exported as well, but not to a single file.
Each chart will be saved as a file in a format that you specify , and references to these graphics files will be placed in the HTML. There is also an option to export all charts (or selected charts) to separate graphics files. Figure 66. Chart in HTML Chapter 6.
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Chapter 7. W orking with Syntax Y ou can save and automate many common tasks by using the powerful command language. It also provides some functionality not found in the menus and dialog boxes. Most commands are accessible from the menus and dialog boxes.
8. T o run the syntax currently displayed, from the menus choose: Run > Selection Editing Syntax In the syntax window , you can edit the syntax. For example, you could change the subcommand /BARCHART to display frequencies instead of percentages. (A subcommand is indicated by a slash.
T o obtain mor e detailed help for the current command, press the F1 key . This takes you directly to the command syntax refer ence information for the current command. Y ou may have noticed that text displayed in the syntax window is colored. Color coding allows you to quickly identify unrecognized terms, since only recognized terms are colored.
The breakpoint is r epresented as a red circle in the region to the left of the command text and on the same line as the command name regardless of where you clicked. When you run command syntax containing breakpoints, execution stops prior to each command containing a breakpoint.
Chapter 8. Modifying Data V alues The data you start with may not always be or ganized in the most useful manner for your analysis or reporting needs. For example, you may want to: v Create a categorical variable from a scale variable. v Combine several response categories into a single category .
3. In the main V isual Binning dialog box, select Household income in thousands [income] in the Scanned V ariable List. A histogram displays the distribution of the selected variable (which in this case is highly skewed). 4. Enter inccat2 for the new binned variable name and Income category [in thousands] for the variable label.
This automatically generates descriptive value labels for each category . Since the actual values assigned to the new binned variable are simply sequential integers starting with 1, the value labels can be very useful.
4. Click the minus (–) button on the calculator pad in the dialog box (or press the minus key on the keyboard). 5. Select Y ears with current employer [employ] and click the arrow button to copy it to the expression. Note : Be careful to select the correct employment variable.
Functions are organized into logically distinct groups, such as a group for arithmetic operations and another for computing statistical metrics. For convenience, a number of commonly used system variables, such as $TIME (current date and time), are also included in appropriate function groups.
income*3<100 & ed=5 In the first example, cases that meet either the Age [age] condition or the Level of education [ed] condition are selected. In the second example, both the Household income in thousands [income] and Level of education [ed] conditions must be met for a case to be selected.
If you're new to dates and times in IBM SPSS Statistics, you can select Learn how dates and times are represented and click Next . This leads to a screen that provides a brief overview of date/time variables and a link, through the Help button, to more detailed information.
Adding a Duration to a Date Y ou can add or subtract durations, such as 10 days or 12 months, to a date. Continuing with the example of the software company from the previous section, consider determining the date on which each customer's initial tech support contract ends.
Chapter 9. Sorting and Selecting Data Data files are not always organized in the ideal form for your specific needs. T o prepar e data for analysis, you can select from a wide range of file transformations, including the ability to: v Sort data. Y ou can sort cases based on the value of one or more variables.
The Split File dialog box is displayed. 2. Select Compare groups or Organize output by groups . (The examples following these steps show the differ ences between these two options.) 3. Select Gender [gender] to split the file into separate groups for these variables.
Sorting Cases for Split-File Processing The Split File procedur e creates a new subgroup each time it encounters a differ ent value for one of the grouping variables. Therefore, it is important to sort cases based on the values of the grouping variables before invoking split-file pr ocessing.
T o select a subset of cases for analysis: 1. From the menus choose: Data > Select Cases... This opens the Select Cases dialog box. Selecting Cases Based on Conditional Expressions T o select cases based on a conditional expression: 1. Select If condition is satisfied and click If in the Select Cases dialog box.
The conditional expression can use existing variable names, constants, arithmetic operators, logical operators, relational operators, and functions. Y ou can type and edit the expression in the text box just like text in an output window . Y ou can also use the calculator pad, variable list, and function list to paste elements into the expression.
v Exactly . A user-specified number of cases. Y ou must also specify the number of cases from which to generate the sample. This second number should be less than or equal to the total number of cases in the data file.
v Copy selected cases to a new dataset. Selected cases are copied to a new dataset, leaving the original dataset unaffected. Unselected cases are not included in the new dataset and are left in their original state in the original dataset. v Delete unselected cases.
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Chapter 10. Sample Files The sample files installed with the product can be found in the Samples subdirectory of the installation directory . There is a separate folder within the Samples subdirectory.
v brakes.sav . This is a hypothetical data file that concerns quality control at a factory that produces disc brakes for high-performance automobiles. The data file contains diameter measur ements of 16 discs from each of 8 production machines. The target diameter for the brakes is 322 millimeters.
v cereal.sav . This is a hypothetical data file that concerns a poll of 880 people about their breakfast prefer ences, also noting their age, gender , marital status, and whether or not they have an active lifestyle (based on whether they exercise at least twice a week).
v dietstudy .sav . This hypothetical data file contains the results of a study of the "Stillman diet" 7 . Each case corresponds to a separate subject and records his or her pre- and post-diet weights in pounds and triglyceride levels in mg/100 ml.
v kinship_dat.sav . Rosenberg and Kim 11 set out to analyze 15 kinship terms (aunt, brother , cousin, daughter , father , granddaughter , grandfather , grandmother , grandson, mother , nephew , niece, sister , son, uncle). They asked four groups of college students (two female, two male) to sort these terms on the basis of similarities.
v property_assess_cs.sav . This is a hypothetical data file that concerns a state assessor's efforts to keep property value assessments up to date on limited resour ces.
v stroke_invalid.sav . This hypothetical data file contains the initial state of a medical database and contains several data entry errors. v stroke_survival. This hypothetical data file concerns survival times for patients exiting a rehabilitation program post-ischemic stroke face a number of challenges.
v verd1985.sav . This data file concerns a survey 18 . The responses of 15 subjects to 8 variables were recor ded. The variables of interest are divided into three sets. Set 1 includes age and marital , set 2 includes pet and news , and set 3 includes music and live .
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Index A Access (Microsoft) 9 B bar charts 24 C cases selecting 73 sorting 71, 73 categorical data 23 summary measures 23 charts bar 24, 29 creating charts 29 histograms 26 computing new variables 65 c.
T text data files reading 12 T ext Import W izard 12 transposing (flipping) rows and columns in pivot tables 37 V value labels assigning 19 controlling display in V iewer 19 numeric variables 19 varia.
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Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il IBM SPSS 22 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del IBM SPSS 22 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso IBM SPSS 22 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul IBM SPSS 22 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il IBM SPSS 22, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del IBM SPSS 22.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il IBM SPSS 22. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo IBM SPSS 22 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
