Using the Frequencies Procedure in SPSS 9.0 for Windows © by Julia Hartman © Copyright 2000, Julia Hartman

July 2000Hartman, JA2 About this tutorial Using the Action Buttons for more informationClick this button to return. Takes you to the next slide Takes you to the previous slide and this button

July 2000Hartman, JA3 About this tutorial This tutorial will show you some of the information you can learn about your data by using the Frequencies procedure. Text written in orange is directly quoted from SPSS 9.0 for Windows © help files.

July 2000Hartman, JA4 About this tutorial Is for users who already know how to open a file in the Data Editor Window This tutorial... Uses the Cars.sav sample data file that can be installed with SPSS 9.0 for Windows ©

July 2000Hartman, JA5 About this tutorial You can work interactively with the tutorial if you open SPSS and use the Windows ® taskbar to switch between the tutorial and SPSS.

July 2000Hartman, JA6 Introduction to Frequencies Probably the most commonly used procedure in statistical applications Used to display the distribution of values for a variable Frequencies A good way to explore your data and to check for errors in data entry or coding

July 2000Hartman, JA7 Introduction (continued) Examples of when to use Frequencies To learn how many girls and how many boys are in a school’s database To learn how scores are distributed on an exam To learn the mean and standard deviation of scores on an exam

July 2000Hartman, JA8 Why use the the Frequencies Frequencies procedure? The Frequencies procedure provides statistics and graphical displays that are useful for describing many types of variables.

July 2000Hartman, JA9 Running the Frequencies procedure Go to Descriptive Statistics Frequencies…. On the menu bar, go to Analyze.

July 2000Hartman, JA10 Selecting variables Click the arrow to move the variables to the window on the right.

July 2000Hartman, JA11 Selecting variables

July 2000Hartman, JA12 Selecting variables You can drag the pointer to select multiple variables.

July 2000Hartman, JA13 Selecting variables You can use the Ctrl key to select multiple variables.

July 2000Hartman, JA14 Specifying statistics When you finish selecting variables, you can specify the statistics to include by clicking Statistics....

July 2000Hartman, JA15 Specifying statistics Right-click to see additional information about a statistic.

July 2000Hartman, JA16 Specifying statistics

July 2000Hartman, JA17 Including charts Click Charts... to include bar charts, pie charts, or histograms in your output.

July 2000Hartman, JA18 Including charts You can choose to have a normal curve superimposed on histograms. Right-click to see additional information.

July 2000Hartman, JA19 Including charts

July 2000Hartman, JA20 Specifying a format Click Format... to control how your output will be organized.

July 2000Hartman, JA21 Specifying a format Select the order of values in your tables. Choose either to organize statistics in a single table or to be displayed with each variable. Limit the output for tables with many categories.

July 2000Hartman, JA22 Specifying a format

July 2000Hartman, JA23 Specifying a format After you have selected variables, statistics, charts, and format, click OK to run the procedure.

July 2000Hartman, JA24 Output OK, go on to the next slide.

July 2000Hartman, JA25 Output: Statistics Most of the statistics for ORIGIN are meaningless because it is a categorical variable.

July 2000Hartman, JA26 Output: MPG Frequency Table

July 2000Hartman, JA27 Output: MPG Frequency Table For example, 15 is displayed for 14.5, as well as for 15.0.

July 2000Hartman, JA28 Output: ORIGIN Frequency Table No category was entered for one case, so it has been identified as “System Missing.”

July 2000Hartman, JA29 Output: MPG Histogram

July 2000Hartman, JA30 Output: Country of Origin Histogram

July 2000Hartman, JA31 The End Congratulations!You’ve completed this tutorial and should be ready to explore your data in SPSS using the Frequencies procedure! Click this button to repeat the tutorial. Click this button to end the tutorial.

July 2000Hartman, JA32 More about task-switching Working this tutorial interactively involves no more than switching back and forth between the Slide Show of the tutorial and the Cars.sav file in SPSS. However, you can’t switch back and forth from the Slide Show unless you’re set up to do so.

July 2000Hartman, JA33 More about task-switching Press the Esc key to stop the slide show. Read the instructions using the Slide View. You will probably need to change your Taskbar Properties to Auto hide. Follow the instructions as you read.

July 2000Hartman, JA34 More about task-switching Right-click your Windows Taskbar Select Properties.

July 2000Hartman, JA35 More about task-switching Check the box next to: Auto hide reduces the taskbar to a thin line at the bottom of your screen. To redisplay the taskbar, point to the thin line. Always on top Auto hide Click OK

July 2000Hartman, JA36 More about task-switching Open SPSS by using the key, or minimize PowerPoint and open SPSS from the Windows desktop. Open the Cars.sav file in SPSS, and you will be able to switch back and forth between SPSS and the PowerPoint Slide Show.

July 2000Hartman, JA37 More about task-switching Your Windows taskbar should now have a button for PowerPoint and a button for SPSS. You can switch between the programs by clicking the appropriate button.

July 2000Hartman, JA38 More about task-switching When you're in SPSS, you get back to this tutorial by clicking the button for the PowerPoint Slide Show. In other words, to get to SPSS from PowerPoint, you click the SPSS button.

July 2000Hartman, JA39 More about task-switching You can restart the slide show at this slide by clicking on the Slide Show button in the lower left corner of the screen. Then click the red Return button to resume the tutorial.

July 2000Hartman, JA40 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA41 Opening a data file Open a file in SPSS from the File menu or with the Open File button. Find the file and click on Open.

July 2000Hartman, JA42 Opening a data file This is what the Cars.sav data window should look like.

July 2000Hartman, JA43 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA44 More about selecting variables Holding the Ctrl key and clicking on variables in the list will select variables in any order.

July 2000Hartman, JA45 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA46 More about specifying a format The frequency table can be arranged according to the actual values in the data or according to the count (frequency of occurrence) of those values, and in either ascending or descending order. However, if you request a histogram or percentiles, Frequencies assumes that the variable is quantitative and displays its values in ascending order.

July 2000Hartman, JA47 More about specifying a format If you produce statistics tables for multiple variables, you can either display all variables in a single table ( Compare variables ) or display a separate statistics table for each variable ( Organize output by variables ).

July 2000Hartman, JA48 More about specifying a format This option prevents the display of tables with more than the specified number of values. When you have a variable with a large number of values (for example, weights of children in a school), the frequency table will be very large, with only a few cases for each value.

July 2000Hartman, JA49 More about specifying a format However, if you choose to suppress the table, you won’t be able to use the table to check the accuracy of your data. For example, you wouldn’t be able to tell if a child’s weight had been entered as 750 pounds, instead of 75. (You can use statistics to identify the maximum and minimum values, but that wouldn’t find another weight entered as 700 pounds.)

July 2000Hartman, JA50 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA51 More about statistics output Categorical Variables Variables that have a limited number of distinct values or categories. Origin is a categorical variable, with values of: 1 = American 2 = European 3 = Japanese

July 2000Hartman, JA52 More about statistics output Statistics such as the mean and standard deviation are based on an assumption of normal distribution. Most of the statistics displayed are not appropriate for categorical data, but the median and mode could be useful.

July 2000Hartman, JA53 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA54 More about Frequency Tables

July 2000Hartman, JA55 More about Frequency Tables Although the table is lengthy, it provides important information. Based on the lowest and highest values in the table, it appears there are no major errors in the data for MPG.

July 2000Hartman, JA56 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA57 The values listed as 16 are actually 15.5 (5 cases), 16.0 (13 cases), and 16.2 (1 case). More about Frequency Tables

July 2000Hartman, JA58 Defining data

July 2000Hartman, JA59 Defining data

July 2000Hartman, JA60 Defining data

July 2000Hartman, JA61 Defining data The variable definition can be changed to display the decimals. Go to the Data menu and select Define Variable...

July 2000Hartman, JA62 Defining data Select Type...

July 2000Hartman, JA63 Defining data The data were entered with one decimal place, so change Decimal Places to 1, then click Continue.

July 2000Hartman, JA64 Defining data Click OK

July 2000Hartman, JA65 Defining data The new Frequency Table, using the new variable definition, displays the actual values for MPG.

July 2000Hartman, JA66 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA67 More about charting Country of Origin

July 2000Hartman, JA68 More about charting Country of Origin In other words, a histogram is not appropriate for a categorical variable like Country of Origin.

July 2000Hartman, JA69 A Bar chart:...displays the frequency count for each value as a separate bar. Bar charts are appropriate for categorical variables…. Values for which the count is zero do not appear in a bar chart. More about charting Country of Origin

July 2000Hartman, JA70 More about charting Country of Origin

July 2000Hartman, JA71 A Pie chart:...displays the frequency count for each value as a separate slice. Pie charts are appropriate for categorical variables…. Values for which the count is zero do not appear in a pie chart. More about charting Country of Origin

July 2000Hartman, JA72 More about charting Country of Origin

July 2000Hartman, JA73 Whoops! You missed the signal to return to the tutorial!

July 2000Hartman, JA74

July 2000Hartman, JA75 Whoops! You missed the signal to return to the tutorial!

Press the Esc key to end the show.