Quake3World

For some reason my brain has froze as I am trying to put some data into a spreadsheet for analysis.

This is ridiculously easy, but for some reason I don't think I'm doing it right...kind of like when you suddenly can't spell a word you use all the time.

Here's the deal.
I've got a test I give that has each question scored on a 4,3,2,1 point scale. I need to figure out the average score per question based on data like this:

Let's say I have 43 total tests I am collecting data for.

Question 1 had 21 four point answers, 10 three point answers, 7 two point answers and 5 one point answers. I need to figure out what the value for the average score was (i.e. 3.2, 2.1, or whatever...) Someone set this up for me please.

I've got a formula in excel that I think is correct, but I'm not certain.

( (21 * 4) + (10 *3) + (7 * 2) + (5 * 1) ) / (21 + 10 + 7 + 5)

eye, that's what I had. But for some reason it just didn't seem right.
thanks.

can't see how it would be different.

it might seem wrong because we are dropping out additional steps. the actual equation is

total points achieved / total points possible = percentage correct

this would be

((21 * 4) + (10 *3) + (7 * 2) + (5 * 1)) / ((21 + 10 + 7 + 5) *4))

but this is only the percentage correct. since we want to total correct out of 4, we times this whole thing by 4.

((21 * 4) + (10 *3) + (7 * 2) + (5 * 1)) / ((21 + 10 + 7 + 5) *4)) * 4

but the 4's can cancel out at this point.

mebbe that's why

Weighted averages?

mjrpes wrote:( (21 * 4) + (10 *3) + (7 * 2) + (5 * 1) ) / (21 + 10 + 7 + 5)

3.1 seems about right given the distribution