MDL-14208 Cache results of calculations, "recompute now" functionality -- added message about when the stats were last calculated and how many attempts there have been since then and a recompute now button.

MDL-14208 'Improvement of Item Analysis Report :  Cache results of calculations, "recompute now" functionality' - using new tables to cache stats results.

MDL-15751 "Quiz statistics report : only list random questions once when there are several consecutiver random questions picking from the same category with the same options to recurse into sub directories"

MDL-15268 "Content for Quiz Statistics report table" fixed a bug where every a row was added to the table for every time a subquestion was attempted.

MDL-15268 "Content for Quiz Statistics report table" seperated quiz item / position stats code into a seperate class in qstats.php and now calculating item statistics too.

MDL-15268 "Content for Quiz Statistics report table" know looping through all question grades fetched from the db to calculate position statistics.

MDL-15384 'change name of quiz report classes to "quiz_{reportname}_report"' easy to do, changed class name of all reports and changed the code in report.php which instantiates the correct class.

MDL-15268 "Content for Quiz Statistics report table" adding more if conditions to only display stuff when the calculations are possible. This depends on how many attempts there have been and how many questions there are.

MDL-15268 "Content for Quiz Statistics report table" some columns of Quiz Statistics report table only make sense if there is more than one question in the quiz. Adding an if condition.

MDL-14204 "Content for Quiz Statistics report table - Random_guess_score" added method random_guess_score to question type objects and a new function in questionlib that calls the question type method.

MDL-14203 "split report into two seperate reports - Quiz Statistics report and Individual Item Analysis report" added start of "Quiz structure analysis" table

MDL-14203 "split report into two seperate reports - Quiz Statistics report and Individual Item Analysis report" added calculations for CIC, ER and SE.

MDL-14203 "split report into two seperate reports - Quiz Statistics report and Individual Item Analysis report" added CIC, ER and SE calculations. Calculation needs debugging.

MDL-14203 "split report into two seperate reports - Quiz Statistics report and Individual Item Analysis report" started quiz statistics report in directory 'statistics'