T test

From: "RAMS" <ramsathish@xxxxxxxxx>
Date: 5 Dec 2005 00:05:00 -0800

Hi all,

I did a t test to compare whether there is any significant
difference between two treatments or not? The SPSS output says that
there is a difference between the two treatments.

But when i go for the 95% confidence interval for the two
treatments individually it was concluded that there is no significant
difference. Beacuse the two confidence intervals are overlapping.

How it works? Below that i have attached my SPSS outputs. anyone
please help me.

Group Statistics

Treatment N Mean Std. Deviation Std. Error Mean
A 5 -2.1642 1.13053 0.50559
B 5 -0.5384 0.96450 0.43134

the variance of the two treatments are tested by Levenes test and that
gives there is no significant difference between the variance of the
two treatments.

the t value =-2.446

p value=0.040

mean difference=-1.6258

standard error of difference=0.66458

.

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