00:01
All right, so we have a little hypothesis test here.
00:03
We have the union of restaurant and food service workers is testing if the mean hourly wages increased, where last year is 8 .25, and they want to see if this year is greater.
00:16
So they did a random sample.
00:18
They found the mean of the sample to be 8 .52, the standard deviation of a buck 20.
00:23
And the null and alternative hypotheses these tests are.
00:30
So the null is that the mean is less than or equal to 8 .25.
00:39
The big one, the important one really, is that the alternative is that the mean is greater than 8 .25.
00:50
Now just to know for the null, you might see this as the mu is equal to 8 .25.
00:58
Sometimes you're a professor, sometimes techs are very specific.
01:02
They want you to have the only possible outcomes in the world.
01:07
So you can either be, let's say the mean, we're looking at 8 .25 here.
01:14
You can either be that value or lower, or you could be strictly greater than the value.
01:21
Like there's only two outcomes.
01:23
So sometimes they want the null to represent that.
01:26
So just be aware.
01:27
So, but we'll say, for our purposes, we'll say it's equal to 8 .25.
01:36
We're testing really for the one direction.
01:39
In the context of the test, what is the type 1 error? type 1 error is rejecting the hypothesis, rejecting the null hypothesis, is rejecting the hypothesis that mu is equal to 8 .25...