Select Cases. Select Cases GRAPHS. The Select Cases command excludes from further. selection criteria. Select Use filter variables

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1 Select Cases GRAPHS The Select Cases command excludes from further analysis all those cases that do not meet specified selection criteria. Select Cases For a subset of the datafile, use Select Cases. In the menu, click Data. Click Select Cases... Select Use filter variables and move the variable you want to select cases from it to the empty box To select only those cases which meet certain criteria, choose the If option.

2 Calculator pad operators Enter the expression that will determine which cases will be selected. Click Continue. Select Cases - The systolic blood pressure for non smokers only From Unselected Cases Are,select Deleted. click OK. Non smoker persons are the only persons who selected While others are deleted Transform to Variable View Change the variable Label to Non smoker Systolic blood pressure

3 Save the new file as 3 nonsmokers selected cases Select Cases - Smoker with normal (Less than 130) systolic blood pressure only Repeat the previous steps with smokers and save the new file as 3 smokers selected cases Enter the expression that will determine which variables will be selected. Click Continue. Don t forget to Change the variable Label to Smoker Systolic blood pressure

4 To select Random sample of cases Note that the selected cases will be approximately cases of the total 100 cases were selected

5 This time only 15 cases of the total 100 cases were selected Repeat the previous steps with both nonsmokers and smokers But use the filtered command instead of Deleted When filtered, the cases that do not meet the selection criteria remain in the data file, but are turned off, much like missing values, so that they are not counted in further analysis. If we want to continue analysis using the whole data set rather than the sub-set we have isolated, we need to go back into the Select Cases dialog box and click on the radio button next to All cases Steps for Analyzing Data Enter the data Select the procedure and options Select the variables Run the procedure Examine the output Frequencies Frequencies gives frequency distributions for all types of data (nominal, ordinal, and interval)

6 Open the 3-smokers selected cases spss file Or Open the original file (1-Entering Data) with smokers as selected and filtered cases. Choose Descriptive Statistics Click Frequencies In the menu, click Analyze This type of dialog box is used for many procedures. Select the Variable/s. Click the arrow to move them to the appropriate box on the right.

7 Output Wait for the output... Click OK to run the Frequencies procedure. Chart button For histograms or other charts, click Charts. Choose the type of chart and click Continue Click Ok Bar chart and Frequencies

8 Click Ok Bar chart and percentage

9 The histogram has gaps for 170 and 200, which are non existent. Positively skewed

10 The Graphical Description of Data Histogram A Histogram is a graphical representation of a frequency distribution for continuous data. The height is proportional to the frequency of that class How to make histogram? From the menus, choose: Graphs and Histogram Select a numeric variable for Variable in the Histogram dialog.

11 Double click on the Graph to go to Chart Editor SPSS allows you to rescale and change quantitative axes in a variety of ways. Changing This can be done the by selecting axes Chart > Axis click the Interval button to edit the horizontal axis and click on OK. Click the Labels... button to change the way the labels are displayed. The interval axis

12 Select Custom to activate the Define button, then click on it to open the Interval Axis: Define Custom Intervals box. Changing the intervals Leave the Decimal Places: 1. Change the interval type to Range. Click the Continue button to get back to the original Interval Axis box. Select Interval width: rather than # of intervals (number of intervals) and type 20 in the Definition section. Change Minimum to 89.5 and Maximum under the Range section. Click on Continue to get back to the Interval Axis box. Click OK to make the changes to the chart.

13 click the Scale button to edit the vertical axis and click on OK. The options in the dialogue box include these: Display axis line box switches the scale axis line on or off. Axis Title: box for typing in a title for the axis. Title Justification: menu changes the place of the title relative to the axis. Scale changes between the ordinary Linear scale to a Log scale, which is not really appropriate for this kind of graph, but may be useful later on. Range changes overall range of the axis by entering new values in the Displayed: Minimum and Maximum boxes. Click Grid as well as Ticks under Major Divisions to draw a grid from the interval axis to help in comparing the count across intervals. Change increments under Major Divisions and to Minor Divisions 5 Click OK to make the change.

14 This histogram is a graphical representation of the distribution of Systolic blood pressure for nonsmokers. The curve represents the normal distribution. Bar charts Bar Charts are used for graphical representation of Nominal and Ordinal data Height of the bar is proportional to the number of values in the category. Summaries for Groups of Cases Categories of a single variable are summarized. Bar height is determined by the Bars Represent option. Example: To see number of males and females from the Gender variable How to? From the menus, choose: Graphs, Bar Select the icon for Simple and select Summaries for groups of cases. Select Define.

15 Select a variable and move it into the Category Axis box. Select % of cases Click Ok A clustered bar graph Two or more variables are summarized within categories of another variable. Two or more Bars Represent variables (Var 1, Var 2). From the menus, choose: Graphs, Bar Select the icon for Clutered and select Summaries for groups of cases. Select Define.

16 Select education level as variable for the category axis and move it into the Category Axis box. Select gender and move it into Define Clusters by box. By clicking on Title You can add title, subtitle and footnotes Select % of cases Click Ok From the menus, choose: Graphs and Bar Select the icon for Clustered and select Summaries of separate variables. Select Define. Select at least two variables and move them into the Bars Represent box. These variables must be numeric.

17 Select a category variable and move it into the Category Axis box. This variable may be numeric, string or long string. A stacked bar graph Each bar is divided into layers, with the area of each layer proportional to the frequency of the category it represents. Pie Diagram The Pie Chart is used to graphically display either The Pie Chart is used to graphically display either qualitative or quantitative data, i.e., can be constructed for all levels of measurement..

18 From the menus choose: Graphs Pie Select Summaries for groups of cases and then Select Define. Select education level as the variable that defines slices and move it into Define Slices by box. This variable may be numeric, string, or long string. Click OK to create the pie chart. The pie chart reveals that most respondents primary school educated. Glancing at the chart, it would appear that only about a quarter of the respondents are not educated at all. You can edit charts in a variety of ways. For this sample pie chart, we will: Add a title. Remove the small category of "missing" data. Display percentages for the remaining categories in the chart. The first thing we'll do is add a title: Double-click the pie chart to open it in the Chart Editor.

19 From the Chart Editor menus choose: Chart Title For Title 1, enter Education level and then click OK. A descriptive title is now displayed above the pie chart. Sometimes you need to remove some category such as none data. To do that: From the Chart Editor menus choose: Series Displayed

20 The category of none data has been removed from the pie chart, leaving only four categories. Move none from the Display list to the Omit list and click OK. Double-click on one of the category labels. Now It might be useful to see the exact percentages. Select (check) Percents While we're here, let's move the category labels from the outside to the inside of the pie. Click Format

21 Select Inside from the drop-down list. Deselect (uncheck) Inside labels to suppress the display frame. Click Continue and then Click OK. Now percentages are displayed along with the category labels -- and both are displayed inside the pie slices. Stem and Leaves Display The percentages are based on the categories displayed ( = 100). If you put the category containing none values back into the pie, the percentages would change. Open 3 Non-smokers selected cases file Select Analyze

22 Transfer the Non smokers Systolic blood pressure variable into the dependent list Plots: to display the variable (s) graphically. Statistics: to display the statistics of the variable (s). Both: to display both plots and statistics.

23 Time Plot Import your data from Excel file Choose the file type Select the Excel file to be opened Mark and delete unnecessary Rows Select the appropriate worksheet

24 Mark and delete unnecessary columns Switch to the variable view Rename the variables Change the type to Numeric Label the variables And change the Measure to Scale

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