Question on Average Improvement (Task 1) Effectiveness of Basic Math Lessons

[Chidinma-Egwuogu]

hello @Kebith and @AddisalemB (haven't heard from her in a while, hope she's good)

Please, I have an issue with calculating the average improvement in task 1.

1. My student didn't get any of their pre-test questions correct and got four of the post-test questions right. In normal percentage calculations, their individual average improvement is 40% (hope I got that math right).

2. But I don't know what calculations we're using in task I. Are we just using the automatic result in the skill result spreadsheets? If so, mine is broken. It's showing an error code and won't calculate the percentage because my student didn't get any pre-test questions right.

I think I should tag @seanlip too.

Please help.

I have added the link so you can view below:

https://docs.google.com/spreadsheets/d/1HX00Bbrl24sKOlqVfxUH7dw3M3cxLDPwDluhgVJItlE/edit?usp=sharing

[Collette-vershalli]

Hi @Chidinma-Egwuogu . You've been missing as well i hope your doing well. But as per your question i don't have an idea i guess only the mentors or one of us will be able to help you out. 😇.

[Nobly143]

Hello @Chidinma-Egwuogu,
I don't know what you're working on but from my knowledge working with spreadsheets the error usually comes when you're trying to divide a number by zero, that's like 2/0 or 3/0.
Maybe you can share the data you're working on and we might figure it out together.

[Chidinma-Egwuogu]

Hi Noble, that's what the error code means right? So, what then should I do please? https://docs.google.com/spreadsheets/d/1HX00Bbrl24sKOlqVfxUH7dw3M3cxLDPwDluhgVJItlE/edit?usp=sharing

Here's the link to the doc.

[Nobly143]

I just looked at the document, the Improvement row with cell G14 has the error and from the formula tab it's showing (F12/C12)-1 as the formula used. The simple fix is C12 cannot be zero but that would mean changing the value of your research which is not ideal.
So I want to know what (F12/C12)-1 is calculating, is it like a percentage or average or something because I have not seen a formula like this.

[Chidinma-Egwuogu]

that's the thing. I'm not sure what it is calculating. But I suppose it's the average improvement percentage, since it was linked to a guide doc. See below for context.

[Nobly143]

Ohh, it's automatically calculated, well only the mentors would be able to interpret the formula so that we can better understand.
This is actually a tricky one you can't change the formula because it was given as part of the document and the only way to get rid of the error is to change the value of C12 from zero.
@Kebith @AddisalemB we need your help.
@Chidinma-Egwuogu I hope it doesn't delay your report.

[Chidinma-Egwuogu]

nah.. i'll just move on to other stuff until I get an answer. Thank you very much Noble.

[zeelyha]

@Chidinma-Egwuogu were you able to resolve this? I'm having the same issue.

[Chidinma-Egwuogu]

Hi @zeelyha , I haven't gotten an answer yet, meanwhile, I just calculated the average improvement myself.

Since my student had scored 0 in the exhaustive pre-test for 10 questions, and later scored 4 for the same number of questions, I deduced that his average improvement was by 40%.

[zeelyha]

Thank you @Chidinma-Egwuogu. I guess I'll just do that too.

[seanlip]

I just took a look at this. The spreadsheet's calculation is: (# correct answers in post-test)/(# correct answers in pre-test) * 100%. This results in an improvement of infinity % because the baseline is 0.

I think what you are thinking of as improvement is more like (% score in post-test - % score in pre-test).

Both calculations are reasonable. The second one is perhaps a bit more robust and avoids the divide-by-zero error. So I have updated the original spreadsheet accordingly. But it doesn't matter too much if you've already made a copy and are using the old formula. It's just important to make sure you understand how the improvement in the spreadsheet is being calculated. If you think it's better to report the results in a way that's different from the formula in the spreadsheet, that is fine.

[zeelyha]

Thank you for this. @seanlip

[Chidinma-Egwuogu]

Thank you for your help @seanlip. I have made a copy and updated the link in my report.