# Standard Deviation? Predicting error??

• Feb 18th 2013, 08:07 PM
AmmyBabyx3
Standard Deviation? Predicting error??
A computer is programmed to predict test scores and the following are the predicted
test scores for the 10 students listed below.
90 90 87 80 42 70 67 60 83 94

For each student fi nd the error in their predicted score. Then calculate the average and
standard deviation of these errors. Comment briefly on how well the computer program
seems to be at predicting scores. Hint: use the interpretation of average and S.D. to
make this assessment.

So for standard deviation, I used this formula I found online: How To Calculate Standard Deviation by sonia
but I'm not sure what it means by "finding the error". Is this the margin of error number? Can someone describe the steps I need to take in order to solve this problem?
• Feb 19th 2013, 02:08 AM
chiro
Re: Standard Deviation? Predicting error??
Hey AmmyBabyx3.

The first thing you need to do is to give a distribution for the scores of the students before you can get parameter estimates (like the standard deviation estimate).

What kind of model do you have in mind for the students?