00:01
So here in this question, the company does a survey and they report that 55 % of people have confidence in the actions of senior management and they're interested in testing if to be 98 % confidence that at least half the employees have confidence in senior management.
00:17
The classic way you would test this is you would make a hypothesis test where you hypothesize that the population portion is 50 % and your alternative that you're testing for is that it's greater than 50%.
00:32
And then your test statistic that you would plug in here, t, would be kind of what we got, p hat minus p over the standard error.
00:40
And remember that the standard error under the null hypothesis would be this right here.
00:45
Here n is tpt.
00:47
We would have this normal distribution and this would be coming from a normal 01 distribution.
01:04
And we're only looking at the upside tail.
01:07
So you would want to be 98 % confidence.
01:10
We would be looking for the critical value above.
01:15
Let's see.
01:16
I'm just going to plug into looking at normal distribution, standard normal and look at the 98 % quantile.
01:23
The 98 % quantile here comes out to be 2 .05375.
01:31
We can call this t star...