00:01
Here we are given a hypothesis test for which the no hypothesis is that the mean is equal to 10, and the alternative hypothesis is that the mean is greater than 10.
00:11
And we are asked to calculate the p -value for several test statistics.
00:19
For part a, we are given the test statistic of 2 .05.
00:30
One thing we can note is that the alternative hypothesis is that the mean is greater than some value, which means that this is a one -sided or upper -tailed hypothesis test.
00:46
And so the p -value is the probability of getting a test statistic greater than z -0.
00:55
So visually, this means, let's suppose our z -0 is here.
01:01
And the alternative hypothesis is that the population mean is greater than some number.
01:09
Then it is an upper -tailed test, and the p -value is this area.
01:14
Which represents the probability of getting a test statistic at least as extreme as z -0.
01:28
And we can do this by finding the value of this or the value of this.
02:05
And this gives us a p -value of 0 .0 -02.
02:14
For part b, we're asked to find the p -value, but this time we're told the test statistic came out to minus 1 .84.
02:34
Now, just going back to the curve, this time we have a test statistic that is, let's say this is negative 1 .84.
02:45
However, based on our alternative hypothesis, this is an upper -tailed test...