Example SPSS

Basic Medical Statistics CourseOctober 2010Wilma Heemsbergen

Windows in SPSS

For each data set: (>1 possible):- Data view- Variable view

Furthermore, a syntax window can be opened

Open windows are shown in the tab “Windows”New windows can be opened: file – new

Data, output, syntax can be saved in separate files

Import Data Sets in SPSS

(*.dbf, *.xls, *txt,/…)

Using the “paste” button, the corresponding syntax is pasted (ready to run).

Get data

GET FILE='U:\data_statcursus\trial_rt.sav'.DATASET NAME DataSet1 WINDOW=FRONT.

Menu: file – open - data

It is also possible to start with opening a syntax file, which will read / open the data (without using the menu). To run: (select and) hit the run button.

Use the “paste” button to get the syntax in the syntax window

Compute

DATASET ACTIVATE DataSet1.COMPUTE duur_rt=tend - tstart.EXECUTE.

Menu: transform - compute

Reports, describing data

Displaying data

Histogram

GRAPH /HISTOGRAM=duur_rt.

Menu: graphs - legacy dialogs - histogram

DescriptivesMenu: analyse - descriptive statistics - descriptives

DESCRIPTIVES VARIABLES=age /STATISTICS=MEAN STDDEV MIN MAX.

Recode

Menu: transform - recode

RECODE age (45 thru 69.99=0) (70 thru 90=1) INTO age70.EXECUTE.

Split file / selection

Menu: data - split file data - select cases

COMPUTE filter_$=(arm=1).VARIABLE LABEL filter_$ 'arm=1 (FILTER)'.VALUE LABELS filter_$ 0 'Not Selected' 1 'Selected'.FORMAT filter_$ (f1.0).FILTER BY filter_$.EXECUTE.

SORT CASES BY arm.SPLIT FILE SEPARATE BY arm.

There is a possibility to savea subset of the variables:“save as”, option “variables”

Try the following to practice with SPSS:(data set and syntax file are available at website)

- Read the file “trial_rt”, using menu. Paste the syntax.- Compute a new variable (save the syntax).- Generate a frequency table, a pie chart, a cross tab,

using: the menu / the paste button / the syntax window.- Generate a frequency table for each rand arm seperately,

using the options “split file” and “select”.- Save file: trial_rt_extended as an SPSS file.- Save a subset of variables (trial_rt_subset)- Save output: output_trial_rt.- Save syntax: syntax_trial_rt_extended.- Open the database again, using your syntax- Save file as a *.txt file or an *.xls file and try to read it

again by importing the data set.