ChArLiE713
New member
- Joined
- May 4, 2010
- Messages
- 1
Heyy everyone, I am new here. I have a BioStatistics final tomorrow and need some help on some things. I have been redoing all my test questions over to get used to them again because I haven't done them in a while. There are these 4 questions that I got wrong on the test and don't remember how to do. If someone can please help me with it and explain to me how to do it, it would be greatly appreciated!
I have pictures of the questions if it makes it easier. There were 7 questions I got wrong and I figured how to do 3 of them. Now if someone can help me with the other four. Numbers 1, 4, 6, 7
http://s8.photobucket.com/albums/a44/13Arod13/?action=view¤t=1126.jpg
http://s8.photobucket.com/albums/a44/13Arod13/?action=view¤t=1127.jpg
1.) In fitting a least square line to n = 20 data points, the following quantities were computed:
SSxx = 65 , SSyy = 250 , SSxy = 100 , x(mean) = 2.5 , and y(mean) = 50
a. Find the least squares line
b. Graph the least square line
c. Calculate SSE
d. Calculate s^2
e. Find a 95% confidence interval for ?1. Interpret the result.
f. Find a 95% confidence interval for the mean value of y when x = 10
g. Find a 95% prediction interval for y when x =10
4.) In each case find the approximate sample size necessary to estimate a proportion p correct to within 0.01 with probability equal to 0.95.
a. Assume you know p is near 0.3
b. Assume you have no knowledge of the value of p, but you wish to be certain that your sample is large enough to achieve the specified accuracy.
6.) An inspector examined a random sample of 400 bottles of shampoo and found that 152 of the bottles had loose bottle-caps that required tightening. Construct a 95% confidence interval for the true proportion of bottle-caps that needed tightening, in the population sampled.
7.) The following table shows the percentages of the vote predicted by a poll for seven candidates fro the U.S. Senate in different states, x, and the corresponding percentages of the vote that they actually received, y.
x 42 34 59 41 53 40 55
y 51 31 56 42 58 35 54
a. Plot the data on a scattergram
b. Calculate the values of r and r^2
c. Is there sufficient evidence to indicate that x and y are linearly correlated? Test at the a = 0.01 level of significance.
Once again, please help. Any help would be greatly appreciated!
I have pictures of the questions if it makes it easier. There were 7 questions I got wrong and I figured how to do 3 of them. Now if someone can help me with the other four. Numbers 1, 4, 6, 7
http://s8.photobucket.com/albums/a44/13Arod13/?action=view¤t=1126.jpg
http://s8.photobucket.com/albums/a44/13Arod13/?action=view¤t=1127.jpg
1.) In fitting a least square line to n = 20 data points, the following quantities were computed:
SSxx = 65 , SSyy = 250 , SSxy = 100 , x(mean) = 2.5 , and y(mean) = 50
a. Find the least squares line
b. Graph the least square line
c. Calculate SSE
d. Calculate s^2
e. Find a 95% confidence interval for ?1. Interpret the result.
f. Find a 95% confidence interval for the mean value of y when x = 10
g. Find a 95% prediction interval for y when x =10
4.) In each case find the approximate sample size necessary to estimate a proportion p correct to within 0.01 with probability equal to 0.95.
a. Assume you know p is near 0.3
b. Assume you have no knowledge of the value of p, but you wish to be certain that your sample is large enough to achieve the specified accuracy.
6.) An inspector examined a random sample of 400 bottles of shampoo and found that 152 of the bottles had loose bottle-caps that required tightening. Construct a 95% confidence interval for the true proportion of bottle-caps that needed tightening, in the population sampled.
7.) The following table shows the percentages of the vote predicted by a poll for seven candidates fro the U.S. Senate in different states, x, and the corresponding percentages of the vote that they actually received, y.
x 42 34 59 41 53 40 55
y 51 31 56 42 58 35 54
a. Plot the data on a scattergram
b. Calculate the values of r and r^2
c. Is there sufficient evidence to indicate that x and y are linearly correlated? Test at the a = 0.01 level of significance.
Once again, please help. Any help would be greatly appreciated!