Presentation on theme: "T-test for dependent samples By: -Mohammed -Zaid - Islam - Omar."— Presentation transcript:
T-test for dependent samples By: -Mohammed -Zaid - Islam - Omar
The concept Drawing the conclusion about the differences between two population means, ( after - before situations), where the same object or item is measured. To detect whether there are any statistically significant differences between these means.
When to use? Dependant t-test used to compare two means on single dependant variables. Comparing the mean of single Sample or two matched or paired samples e.g: Students result in ( march ) and in ( June). N=10 March = ( 75, 80, 70, 90, 85, 79, 81, 60, 55, 91) June = ( 80, 85, 76, 90, 89, 84, 88, 69, 62, 97) Name the variables appropriately in the VARIABLE VIEW and adjust the decimals column appropriately.
Interpreting the data of T-test dependant using SPSS How to interpret
If below.05 REJECT difference expected difference observed
References : 1. Understandable Statistics: Concepts and Methods By Charles Henry Brase, Corrinne Pellillo Brase. 2. http://en.wikipedia.org/wiki/T-test#Dependent_t-test_for_paired_sampleshttp://en.wikipedia.org/wiki/T-test#Dependent_t-test_for_paired_samples 3. http://statistics.laerd.com/spss-tutorials/dependent-t-test-using-spss- statistics.phphttp://statistics.laerd.com/spss-tutorials/dependent-t-test-using-spss- statistics.php 4. Statistics in plain English By Timothy C. Urdan
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