Question

The following data represent the math SAT scores for a random sample of seniors from three different high schools.

School A	School B	School C
488	445	618
592	370	525
537	382	651
470	423	647
539	523	543

Using α=0.05, perform a hypothesis test to determine if the math median SAT score differs among these three high schools.

Answer 1

Hypotheses are:

H0: median SAT score are all same among these three high schools.

Ha: median SAT score differs among these three high schools.

Now enter data in SPSS as shown below:

Variable view:

Data View:

Click on Analyze->Non-Parametric Tests->Legacy->k Independent samples

Move SAT Score to Test Variable List.

Move School to Grouping Variable

Click on Define Range

Enter 1 as minimum and 3 as maximum

Check Median and click OK

The output is shown below

Since p-value = 0.031 < 0.05, reject null hypothesis. We can conclude that median SAT score differs among these three high schools.