00:01
So we have a two sample t test with independent means.
00:06
And i'm actually going to use a ti 84.
00:09
I don't have access to other software.
00:12
And so i have entered these data into my calculator in list one and list two.
00:18
And we would be assuming that the mean number of depression episodes over that span of time for people within that first group.
00:27
And these people have these psychotherapy.
00:30
The therapy, as well as the meds.
00:35
And these people in group two just had the medication.
00:39
We're going to assume that those number of episodes, that they're equal, and alternately that the therapy is reducing the number of depression episodes.
00:50
And so when we do this calculation, i'm not going to pool the values together for the standard deviation.
00:57
I'm going to do this as just independent values.
01:02
And so i'm not pooling.
01:05
And i find that the mean for that first group, the mean, and as i was typing a man, you definitely could see a difference, that the sample size is 10 for each, and that the standard deviation for that first group is 2 .59.
01:22
And again, the sample size is 10 for each.
01:26
And then the sample size for the second group is 10.
01:30
And the mean is 25 .9 with a sample standard deviation of 2 .183.
01:37
Now, again, you might be doing pooling.
01:40
I don't know.
01:41
So i can actually show you the statistics both ways.
01:44
So if you are not pooling, not pooling means you are not assuming that these standard deviations are equal.
01:52
You would get your test statistic, your t value, to be the difference between these two, the 18 .6, minus the 25 .5...