Moodle in English: couple questions about "edit datasets page" in calculated questions

Quiz

couple questions about "edit datasets page" in calculated questions

This discussion has been locked because a year has elapsed since the last post. Please start a new discussion topic.

Hi,

the Edit Datasets page is so confusing (as really stated in moodle docs), I do not know why it looks like a complicated page (for the teacher) !!

I have a calculated question that simply multiplies {b} by 10, please try to asnwer the questions in the attached two images below :

the second image is :

thank you so much in advance for you help.

Average of ratings: -

Permalink | Reply

Your questions illustrate well the difficulty of handling all the calculated question parameters.

The Correct answer is calculated from the formula i.e. 55*10 = 550 which is the true value after conversion using the settings of significant figures.

As I can deduced 550 is 5.5*10² which has been rounded to 1 digit i.e. 6 *10² and expressed as the Correct answer 600 that will be shown to the student once he answered the question.

However all the calculations and grading will be done with the true value i.e 550 +- 0.01 relative i.e. +-5.5 so you should get Min 545.5 Max 555.5.
However when PHP (or C) handle real numbers, they do not handle them perfectly as with integer.
There is a precision limit and this precision limit has been added to the grading limit so that the student always receive the best grade.
Here the precision limits seems to be 1 *10^-11giving the Min 544.499999999 and 555.50000000001

So edit your question and change your settings for Correct answer so that a sufficient number of figures are displayed in relation to your Tolerance settings.

In 2.0 these settings for Tolerance and Correct answer will be available in the page (Edit the datasets) to help solve those problems.

Pierre

Average of ratings: -

Permalink | Show parent | Reply

I'm sorry Mr. Pierre, but your answer was unclear

my question was WHY 55 *10 <> 550 ? you have written something weird : 5.5 * 10²

what if the teacher wants to put the same numbers in the quiz (55 * 10), what should he do in order to get 550 not 600 ??

the tolerance for the above example was relative and is ZERO !! and the significant figures (which I can't understand its function up to this mement although I read the unclear moodle docs about it) was set to show 1 significant figures in correct answer !!

so, I'm totally lost with this type of [ COMPLICATED ] questions ....

Average of ratings: -

Permalink | Show parent | Reply

I need to reproduce your values, more news tomorrow.

At first sight tolerance 0 relative seems to default to 0.01 relative i.e. 1%.

In the mean time use your electronic calculator to multiply
1 000 000 000 * 1 000 000 000 *1 000 000 000 i.e (1*10⁹)³ , you should have 1.0000*10²⁷as result.

Pierre

P.S. which moodle version do you use ?
P.S. Once I have finished reviewing the new code for Moodle 2,0, improving the docs is next on my todo list.

Average of ratings: -

Permalink | Show parent | Reply

moodle 1.9.4 ...

thank you for your efforts

Average of ratings: -

Permalink | Show parent | Reply

can anybody clarify what's going on this page ?

Average of ratings: -

Permalink | Show parent | Reply

"can anybody clarify what's going on this page ?"
Could you be more precise about this sentence.

the main purpose of this third calculated question edit page is to generate the numerical values sets that will be used in the calculated question submitted to the students.
These numerical values are generated in an interval that the teacher can set.
The moodle code verifies that the correct response is inside the limits of the formulas results and display an error message if necessary.
The teacher should generate at least one dataset and up to 100 datasets.

Pierre

P.S. In 2.0 there will be an additional simplified version of calculated question.

Average of ratings: -

Permalink | Show parent | Reply

thank you Mr. Pierre for your help ...

Average of ratings: -

Permalink | Show parent | Reply

reminder ...

Average of ratings: -

Permalink | Show parent | Reply

Hi guys.

I've been using Moodle 1.9.10 and I've worked a lot with calculated quiz questions. The edit Datasets page has been a difficult one, but I know appreciate those two lines of information Murad mentioned.

As I understand it, the first line shows the range of values (max and min)Moodle will accept as correct, based on the tolerance value set on the first page of the question.

The second line shows the effect of the significant figure (SF)/decimal places (DP) setting (1st editing page). E.g. 550 = 600 if rounded to 1 SF. I usually set this to 2 DP or 3 SF.

This is why the 2nd example has given back an error - the rounded figure is now outside the limits of the maximum and minimum.

Hope you find this helpful.

Average of ratings: -

Permalink | Show parent | Reply

Thanks for your comments.

It will be interesting if you can put them in the calculated questiontype moodle docs as they came from a real user and not from this feature designer.

Pierre

P.S. This does not release me of improving the docs which unfortunately as a lower prority than improving the code...

Average of ratings: -

Permalink | Show parent | Reply