00:01
We've been given the z score, the test statistic.
00:03
We want to find the p value at the same.
00:07
So let's start drawing the initial, which the z score is coming from.
00:12
Very poorly.
00:13
I'm just drawing again.
00:16
So minus 1 .56 will be below 0, so it's over here.
00:23
And what we are interested in is the probability of getting something this extreme based on this normal curve.
00:31
This is left tails, so there's only one.
00:34
One rejection region here, over here.
00:37
So let's find out what this area is.
00:39
This area is the probability of getting something this one or lower.
00:45
So p -value here is the probability of a statistic this low or lower.
01:01
Let's find out.
01:02
So we're going to be using the normal distribution.
01:05
So you can use a z -score table, you can use your graphical calculator, or you can use excel.
01:11
There are two types of table, or two functions, standard and cumulative.
01:17
Standard gives you the area between the z score and 0.
01:22
So if you put this into the standard, it would give you this, which isn't what you want...