MDL-15268 "Content for Quiz Statistics report table" more columns of Quiz Statistics report table.

lang/en_utf8/quiz_statistics.php

@@ -12,8 +12,10 @@ $string['quizname'] = 'Quiz name';
 $string['coursename'] = 'Course name';
 $string['nooffirstattempts'] = 'Number of first attempts';
 $string['noofallattempts'] = 'Total number of attempts';
-$string['statsforfirstattempts'] = 'Statistics for first attempts';
-$string['statsforallattempts'] = 'Statistics for all attempts';
+$string['statsfor'] = 'Statistics (for $a)';
+$string['attempts'] = 'Attempts';
+$string['firstattempts'] = 'for first attempts';
+$string['allattempts'] = 'for all attempts';
 $string['firstattemptsavg'] = 'Average grade of first attempts';
 $string['allattemptsavg'] = 'Average grade of all attempts';
 $string['attemptsall'] = 'all attempts';
@@ -33,4 +35,5 @@ $string['quizstructureanalysis'] = 'Quiz structure analysis';
 $string['questiontype'] = 'Q type';
 $string['intended_weight'] = 'Intended question weight';
 $string['random_guess_score'] = 'Random guess score';
+$string['facility'] = 'Facility index';
 ?>

mod/quiz/report/statistics/report.php

@@ -142,13 +142,14 @@ class quiz_report extends quiz_default_report {
         if (!$table->is_downloading()) {
             if ($useallattempts){
                 $usingattempts = $allattempts;
-                $usingattempts->heading = get_string('statsforallattempts', 'quiz_statistics');
+                $usingattempts->attempts = get_string('allattempts', 'quiz_statistics');
                 $usingattempts->sql = '';
             } else {
                 $usingattempts = $firstattempt;
-                $usingattempts->heading = get_string('statsforfirstattempts', 'quiz_statistics');
+                $usingattempts->attempts = get_string('firstattempts', 'quiz_statistics');
                 $usingattempts->sql = 'AND qa.attempt=1 ';
             }
+            $usingattempts->heading = get_string('statsfor', 'quiz_statistics', $usingattempts->attempts);
             print_heading($usingattempts->heading);
             if (($usingattempts->countrecs/2)==floor($usingattempts->countrecs/2)){
                 //even number of attempts
@@ -228,25 +229,25 @@ class quiz_report extends quiz_default_report {
                 }
                 //CIC, ER and SE.
                 //http://docs.moodle.org/en/Development:Quiz_item_analysis_calculations_in_practise#CIC.2C_ER_and_SE
+                list($qsql, $sqlparams) = $DB->get_in_or_equal(array_keys($questions), SQL_PARAMS_QM);
+                array_unshift($sqlparams, $quiz->id);//put quiz id in at beginning of array
                 $qgradeavgsql = "SELECT qs.question, AVG(qs.grade) FROM " .
                         "{question_sessions} qns, " .
                         "{question_states} qs, " .
-                        "{question} q, " .
                         $fromqa.' '.
                         'WHERE ' .$whereqa.
                         'AND qns.attemptid = qa.uniqueid '.
-                        'AND qs.question = q.id ' .
-                        'AND q.length > 0 '.
+                        'AND qs.question '.$qsql.' ' .
                         $usingattempts->sql.
                         'AND qns.newgraded = qs.id GROUP BY qs.question';
-                $qgradeavgs = $DB->get_records_sql_menu($qgradeavgsql, array($quiz->id));
+                $qgradeavgs = $DB->get_records_sql_menu($qgradeavgsql, $sqlparams);
+                
                 $sum = 0;
-                $sql = 'SELECT ' .
+                $sql = 'SELECT COUNT(1) as s,' .
                         'SUM(POWER((qs.grade - ?),2)) AS power2 ' .
                         'FROM ' .
                         '{question_sessions} qns, ' .
-                        '{question_states} qs, ' .
-                        '{question} q, ' .
+                        '{question_states} qs, '.
                         $fromqa.' '.
                         'WHERE ' .$whereqa.
                         'AND qns.attemptid = qa.uniqueid '.
@@ -255,11 +256,15 @@ class quiz_report extends quiz_default_report {
                         'AND qns.newgraded = qs.id';
                 foreach ($qgradeavgs as $qid => $qgradeavg){
                     $params = array($qgradeavg, $quiz->id, $qid);
-                    $power = $DB->get_field_sql($sql, $params);
-                    if ($power === false){
+                    $fromdb = $DB->get_record_sql($sql, $params);
+                    if ($fromdb === false){
                         print_error('errorpowerquestions', 'quiz_statistics');
                     }
-                    $sum += $power;
+                    $questions[$qid]->facility = $qgradeavg / $questions[$qid]->grade;
+                    $questions[$qid]->power = $fromdb->power2;
+                    $questions[$qid]->s = $fromdb->s;
+                    $questions[$qid]->sd = sqrt($questions[$qid]->power / ($questions[$qid]->s -1));
+                    $sum += $questions[$qid]->power;
                 }
                 $sumofvarianceforallpositions = $sum / ($usingattempts->countrecs -1);
                 $p = count($qgradeavgs);//no of positions
@@ -277,7 +282,7 @@ class quiz_report extends quiz_default_report {
         if (!$table->is_downloading()){
             print_heading(get_string('quizstructureanalysis', 'quiz_statistics'));
         }
-        $table->setup($quiz, $cm->id, $reporturl);
+        $table->setup($quiz, $cm->id, $reporturl, $s);
         foreach ($questions as $question){
             $table->add_data_keyed($table->format_row($question));
         }

mod/quiz/report/statistics/statistics_table.php

@@ -13,7 +13,7 @@ class quiz_report_statistics_table extends flexible_table {
      * Setup the columns and headers and other properties of the table and then
      * call flexible_table::setup() method.
      */
-    function setup($quiz, $cmid, $reporturl){
+    function setup($quiz, $cmid, $reporturl, $s){
         $this->quiz = $quiz;
         $this->cmid = $cmid;
         // Define table columns
@@ -35,12 +35,22 @@ class quiz_report_statistics_table extends flexible_table {
         $columns[]= 'name';
         $headers[]= get_string('questionname', 'quiz');
         
-        $columns[]= 'intended_weight';
-        $headers[]= get_string('intended_weight', 'quiz_statistics');
-        
+        $columns[]= 's';
+        $headers[]= get_string('attempts', 'quiz_statistics');
+
+        if ($s>1){
+            $columns[]= 'facility';
+            $headers[]= get_string('facility', 'quiz_statistics');
+            
+            $columns[]= 'sd';
+            $headers[]= get_string('standarddeviation', 'quiz_statistics');
+        }
         $columns[]= 'random_guess_score';
         $headers[]= get_string('random_guess_score', 'quiz_statistics');
         
+        $columns[]= 'intended_weight';
+        $headers[]= get_string('intended_weight', 'quiz_statistics');
+        
         $this->define_columns($columns);
         $this->define_headers($headers);
         $this->sortable(false);
@@ -96,11 +106,21 @@ class quiz_report_statistics_table extends flexible_table {
 
     function col_random_guess_score($question){
         $randomguessscore = question_get_random_guess_score($question);
-        if (is_number($randomguessscore)){
+        if (is_numeric($randomguessscore)){
             return number_format($randomguessscore * 100, 2).' %';
         } else {
             return $randomguessscore; // empty string returned by random question.
         }
     }
+    
+    function col_sd($question){
+        return number_format($question->sd*100 / $question->grade, 2).' %';
+    }
+    function col_s($question){
+        return $question->s;
+    }
+    function col_facility($question){
+        return number_format($question->facility*100, 2).' %';
+    }
 }
 ?>