00:01
For this problem, i'm going to be using excel to calculate the chi -squared statistic just because it's going to make doing the calculations a little bit faster.
00:09
Of course, what i'll be doing is i'll still go through everything step by step.
00:12
I'm just using excel basically as a fancy calculator.
00:16
So first thing that we want to do is find our column totals and our row totals.
00:22
We have that the formulas for figuring out our expected values are given in the assignment sheet there, so i won't belabor the point.
00:33
But we have our observed values, and then we want to calculate our expected values.
00:37
Now if you are using something like excel, we would find the expected values by doing something like this.
00:42
So we do $e2 to get the first row total times $b5 to get the first column total divided by 300.
00:56
Now because of the use of those dollar signs, that basically tells excel that those aspects or those terms or those portions, i guess we could say, of the designated cells shouldn't change.
01:10
So if we go across the first row, we can see that we're still referencing that totals column.
01:15
And similarly, as we go down the rows, we're still referencing that totals row.
01:20
So now that we have our expected values, we want to calculate our squared residuals, the o minus e squared over e's.
01:28
So for the first one, we have that that should be 90 minus 60 .66667 squared divided by 60 .67, roughly...