00:01
So for this data we have a sample size of 11 and we want to predict with our regression equation what the, predict the mean head circumference of children who are 25 .75 inches tall.
00:17
And so plugging that into my model, i have that model on my calculator right now and let's see, 25 .75, plugging into that model i end up getting a predicted value of 17 .1985.
00:35
Now i'm just going to store that value into alpha a so i don't have to type that in again.
00:41
I'm going to mark it right there so i remember.
00:43
Now we want to find a 95 % confidence interval for that mean head circumference for children who are 25 .75 inches tall.
00:51
So we have 17 .1985 plus or minus and we need a t value since we're doing 95 % with .025 in the upper tail and we'll have 10 degrees of freedom.
01:04
And that value corresponds with 2 .228.
01:11
And now we need the standard error and or that standard deviation of the e and let me quickly go to my test to get that back on my calculator and that value is .09538...