The first step of statistical analysis is usually inspecting descriptive statistics.
Analyze → Descriptive Statistics → Frequencies (how many people, percentage, males,
missing v.)
Analyze → Descriptive Statistics → Descriptives (the mean, standard deviation)
Create a histogram of a variable:
- Navigate to Graphs → Legacy Dialogs → Histogram
● Make sure to check the box 'Display Normal Curve'
Create a scatter plot:
● Navigate to Graphs > Legacy dialogs > Scatter/dot .
● Choose a Simple scatter and click on Define.
● Now put the variable Instructions on the x-axis, and Usefulness on the y-axis.
● Click 'Ok' to run the analysis.
To find errors, you can sort the data file by a variable.
- Data → Sort Cases and then delete the stange value
To compare groups (smokers, non-smokers);
- Data → Split File → Compare Groups and choose the variable you want them to be
grouped by
- Then you can calculate the descriptive statistics again.
The difference between the sample mean and the test value = the mean difference
Reversing variables:
You can either compute a new variable (Transform → Compute Variable) with the formula
new var = 3 - old var, or you can recode the original variable (Transform → Recode
into Different Variables) and specify the old and new values manually.
, Compute a new variable
Using a wide variety of mathematical functions, you can compute new variables based on highly
complex equations.
1. From the menus in the Data Editor window choose: Transform > Compute Variable...
2. For Target Variable, enter jobstart.
3. Select Age in years [age] in the source variable list and click the arrow button to copy it to the
Numeric Expression text box.
4. Click the minus (–) button on the calculator pad in the dialog box (or press the minus key on the
keyboard).
5. Select Years with current employer [employ] and click the arrow button to copy it to the expression.
Recode a variable
● Navigate to Transform → Recode into Different Variables
● Select the first input variable
● Name the first output variable ….rec
● Click ‘Change’ ; the screen should now show this: vmat12 → vmat12rec
● Click the button “Old and New Values” and
-10 thru -1 -> 1
0 -> 2