The problem was with the alignment of:
* tables inside the choices.
* Lists inside the choices.
* The specific feedback, when it spanned mulitple lines.
The problem was introduced by MDL-39420.
Certainty -1 has never been used in standard Moodle, but is
used in Tony-Gardiner Medwin's patches to mean 'No idea' which
we intend to implement: MDL-42077. In the mean time, these changes
avoid errors for people who have used TGM's patches.
We now compute the average CBM score, accuracy, CBM bonus and enhanced
accuracy, both for the entire quiz, and for just the questions answered.
Note that these calculations must work correctly in the presence of
descriptions, ungraded questions, and manually graded questions. For
example, imagine a essay added at the end of the quiz "Summarise what
you learned attempting this exercise." This might have max mark zero or
non-zero. The CBM statistics just ignores questions like that.
We now change so that minfraction is -6 and maxfraction is 3, so getting
the question right a low certainty gives maxmark marks, and you get a
bonus for being more confident (rather than being penalised for being
unconfident). Mathematically it is the same, but the difference is
importnat psychologically.
We also change how partially correct scores are handled.
It is too harsh to penalise a partially correct score with full
certainty by doing a linear interpolation between -6 and +3. Instead,
any partially correct score (e.g. 0.5) becomes that fraction of the
correct score (e.g. 0.5 * 3 = 1.5). Also, any incorrect score is treated
as 0, so if you have a multiple choice question that normally gives a
negative score for a wrong choice, this will now never give a score of
less than -6.
Finally we change how this is displayed to students beside the question.
Rather than saying "Marked out of 1.00", we say "Base mark 1.00", and
then later we say "CBM mark 3.00" (or whatever it is).
This parallels question_attempt->minfraction, which allows the
fractional mark to go below zere.
This is needed to allow the certainty-base marking behaviours to work
better.
At the top of the quiz reivew page, there is a table that summarises
infomration about the quiz attempt as a whole. For some question
behaviours, we would like to be able to add additional information to
that summary.
This commit introduces a generic method for the behaviour to provide
summary information about an entire question usage.
It was always a bit of a hack to use static methods on the
qbehaviour_whatever classes to return metadata about the behaviour. It
is better design to have real qbehaviour_whatever_type classes to report
that metadata, particularly now that we are planning to add more such.
For example, inheritance works better with real classes. See, for
example, the improvements in
question_engine::get_behaviour_unused_display_options().
This change has been implemented in a backwards-compatbile way. Old
behaviours will continue to work. There will just be some developer debug
output to prompt people to upgrade their code properly.
This field is not used, but sometimes causes errors when we try to
instert a value that is too long to fit. Therefore remove it.
At the same time, rename tables and columns to match the coding
guidelines.
quiz_question_statistics_stats renamed to question_statistics_calculator
separate class question_statistics used to store calculated stats
and api changed, also code generally cleaned up.
quiz_question_statistics_stats renamed to question_statistics_calculator
separate class question_statistics used to store calculated stats
and api changed, also code generally cleaned up.
* FEATURE_USES_QUESTION_BANK is now a module_supports flag which declares
that an activity uses the question engine.
* question_module_uses_questions can be used to determine if a module
uses the question bank.
After much discussion, it was decided that the damage done by not
not setting question text (student goes to take test and sees nothing)
is more of a problem then the use cases where teachers want empty
questions (inputing paper tests). In those cases, they will need
to add something like a period to the question text field.
to question bank
- move cron to clean up old cache records move code and
rename classes
- further review of the quiz reports statistics code
- starting to separate calculations of quiz stats, question stats and
response analysis
- introduce hashcode db field for cached stats convert
- code to use qubaids hashcode for caches
We just drop the old tables (including previous upgrade steps) and
re-create the new ones, because these tables just cache calculated
statistics. No important data is stored in them.
