00:01
Okay, so this time we have a table with us.
00:05
Okay, so let us just look at the table.
00:08
We have x and the values are 0 1, 2, 3, 4.
00:14
0 1, 2, 3, 4.
00:19
All right.
00:21
Then we have the observed frequencies, right, the observed values.
00:29
And then we have the expected values.
00:34
Whenever we are solving these goodness of fit questions or kai square questions, in general, we should always have the table with us.
00:43
Okay, what are the observed values? 260, 400, 280.
00:53
260, 400, 280, 50, 10.
01:00
All right, what are the expected values? now, over here, we have expected values with us.
01:08
If we would not have the expected values with us, okay? if that were to be the case that we do not have the expected values.
01:16
Values with us, we'll have to calculate that.
01:18
We'll have to calculate that.
01:19
And what is the formula for that? it is sample size, sample size, which is also given as n, multiplied by the probability for each category, multiplied by the probability, probability for each category.
01:42
Over here we are calculating for the ieth category i, for category i, right? so how do you calculate the sample size? it is nothing but the addition of this the observed counts so this is 200 plus 200 400 400 400 is 800 880 940 990 and 10 is 1000 so this is 1 ,000 so our sample size is 1 ,000 okay now luckily we do not have to calculate the expected values they are already given to us so this is 240 .1 and 411 .6 so this is 240 oh so this is 240 .1.
02:38
This is 411.
02:41
Something.
02:42
What is this? 411 .6.
02:45
Then 264 .6.
02:47
Point six.
02:48
This is 264 .6.
02:53
Then we have 75 .6 and 8 .1.
02:56
75 .6 and 8 .1.
03:01
Okay.
03:03
These are the expected values.
03:05
Now we have the observed and the expected values.
03:06
Expected values.
03:09
What is the next step? the next step happens to be to calculate the kai square statistic.
03:15
How do you calculate the kai square statistic? well, what you do for all the categories is you can find the difference between the observed and the expected values.
03:24
You square the difference.
03:25
You divide this difference by the expected value.
03:28
And after doing this for all the categories, you add them all up.
03:31
So this is a summation sign.
03:33
Let us look at this formula let's apply it over here so now let's say for the first category that is zero by the way in this question the null and the alternative hypotheses are already given to us so we don't have to worry much about that okay so yeah the difference between observed and expected this is going to be 260 minus 240 .1 there's a 19 .9 we square this 19 .9 and we divide this by 240 .1 40 .1 1 .6493 so this value is 1 .6493 okay then we have 411 .6 minus 400 this is the difference the difference is 11 .6 we squared it 134 .56 and divide this by 411 .6 this is the expected value so this is 0 3269 0 .36 9.
04:41
All right.
04:42
Then the difference is 264 .6 minus 280 or 280 minus 24 .6.
04:49
That's one and the same.
04:52
We square this 15 .4 square is 237 .16 .16.
04:58
And we divide this by 264 .6.
05:03
This is 08962 .0 .896 .6.
05:13
Okay, then 75 .6 minus 50.
05:17
This is 25 .6.
05:20
We square this, right? this is 65 .5 .6...