| ';
- $Ptr .= 'print("$nIndex) $Temp --> ($nStudent) $Proc{$Temp}
");
- $Sum1=0;
- $Sum2=0;
- $nStudent=0;
- }
-
- return %Proc;
-}
-
-#------- Creating Discimination factor
-sub Discriminant {
- my ($discriminantFactor)=@_;
- my @discriminantKeys=keys(%$discriminantFactor);
- my $Count = scalar @discriminantKeys;
-
- my $UpCnt = int(0.27*$Count);
- my $low=0;
- my $up=$Count-$UpCnt;
- my @UpList=();
- my @LowList=();
-
- $Count=0;
- foreach my $key (sort(@discriminantKeys)) {
- $Count++;
- if($low < $UpCnt || $Count > $up) {
- $low++;
- my $str=$discriminantFactor->{$key};
- foreach(split(/\:/,$str)){
- if($_) {
- if($low<$UpCnt) { push(@LowList,$_); }
- else { push(@UpList,$_); }
+sub ExtractStudentData {
+ my ($cache, $students)=@_;
+
+ my @problemList=();
+ my %problemData;
+ foreach my $sequence (split(':', $cache->{'orderedSequences'})) {
+ foreach my $problemID (split(':', $cache->{$sequence.':problems'})) {
+ foreach my $part (split(/\:/,$cache->{$sequence.':'.
+ $problemID.
+ ':parts'})) {
+ my $id = $sequence.':'.$problemID.':'.$part;
+ push(@problemList, $id);
+ my $totalTries = 0;
+ my $totalAwarded = 0;
+ my $correct = 0;
+ my $correctByOverride = 0;
+ my $studentCount = 0;
+ my $maxTries = 0;
+ my $totalFirst = 0;
+ my @studentTries=();
+ foreach(@$students) {
+ my $code = $cache->{"$_:$problemID:$part:code"};
+
+ if(defined($cache->{$_.':error'}) || $code eq ' ' ||
+ $cache->{"$_:$problemID:NoVersion"} eq 'true') {
+ next;
+ }
+
+ $studentCount++;
+ my $tries = $cache->{"$_:$problemID:$part:tries"};
+ if($maxTries < $tries) {
+ $maxTries = $tries;
+ }
+ $totalTries += $tries;
+ push(@studentTries, $tries);
+
+ my $awarded = $cache->{"$_:$problemID:$part:awarded"};
+ $totalAwarded += $awarded;
+
+ if($code eq '*') {
+ $correct++;
+ if($tries == 1) {
+ $totalFirst++;
+ }
+ } elsif($code eq '+') {
+ $correctByOverride++;
+ }
}
+
+ my $studentTriesJoined = join(':::', @studentTries);
+ $problemData{$id.':sequenceTitle'} =
+ $cache->{$sequence.':title'};
+ $problemData{$id.':studentCount'} = $studentCount;
+ $problemData{$id.':totalTries'} = $totalTries;
+ $problemData{$id.':studentTries'} = $studentTriesJoined;
+ $problemData{$id.':totalAwarded'} = $totalAwarded;
+ $problemData{$id.':correct'} = $correct;
+ $problemData{$id.':correctByOverride'} = $correctByOverride;
+ $problemData{$id.':wrong'} = $studentCount -
+ ($correct + $correctByOverride);
+ $problemData{$id.':maxTries'} = $maxTries;
+ $problemData{$id.':totalFirst'} = $totalFirst;
}
}
}
- my %DisUp = &ProcessDiscriminant(\@UpList);
- my %DisLow = &ProcessDiscriminant(\@LowList);
- return (\%DisUp, \%DisLow);
+ my @upperStudents1=();
+ my @lowerStudents1=();
+ my @upperStudents2=();
+ my @lowerStudents2=();
+ my $upperCount = int(0.27*scalar(@$students));
+ # Discriminant Factor criterion 1
+ my $sortedStudents = &SortDivideByTries($students,$cache,':totalAwarded');
+
+ for(my $i=0; $i<$upperCount; $i++) {
+ push(@lowerStudents1, $sortedStudents->[$i]);
+ push(@upperStudents1, $sortedStudents->[(scalar(@$students)-$i-1)]);
+ }
+
+ $problemData{'studentsUpperListCriterion1'}=join(':::', @upperStudents1);
+ $problemData{'studentsLowerListCriterion1'}=join(':::', @lowerStudents1);
+
+ # Discriminant Factor criterion 2
+ $sortedStudents = &SortDivideByTries($students, $cache, ':totalSolved');
+
+ for(my $i=0; $i<$upperCount; $i++) {
+ push(@lowerStudents2, $sortedStudents->[$i]);
+ push(@upperStudents2, $sortedStudents->[(scalar(@$students)-$i-1)]);
+ }
+ $problemData{'studentsUpperListCriterion2'}=join(':::', @upperStudents2);
+ $problemData{'studentsLowerListCriterion2'}=join(':::', @lowerStudents2);
+
+ $problemData{'problemList'} = join(':::', @problemList);
+
+ return \%problemData;
+}
+
+sub SortDivideByTries {
+ my ($toSort, $data, $sortOn)=@_;
+ my @orderedData = sort { ($data->{$a.':totalTries'}) ?
+ ($data->{$a.$sortOn}/$data->{$a.':totalTries'}):0
+ <=>
+ ($data->{$b.':totalTries'}) ?
+ ($data->{$b.$sortOn}/$data->{$b.':totalTries'}):0
+ } @$toSort;
+
+ return \@orderedData;
+}
+
+sub SortProblems {
+ my ($problemData,$sortBy,$sortProblems,$ascend)=@_;
+
+ my @problems = split(':::', $problemData->{'problemList'});
+ if($sortBy eq "Homework Sets Order") {
+ return \@problems;
+ }
+
+ my $data;
+
+ if ($sortBy eq "#Stdnts") { $data = ':studentCount'; }
+ elsif($sortBy eq "Tries") { $data = ':totalTries'; }
+ elsif($sortBy eq "Mod") { $data = ':maxTries'; }
+ elsif($sortBy eq "Mean") { $data = ':mean'; }
+ elsif($sortBy eq "#YES") { $data = ':correct'; }
+ elsif($sortBy eq "#yes") { $data = ':correctByOverride'; }
+ elsif($sortBy eq "%Wrng") { $data = ':percentWrong'; }
+ elsif($sortBy eq "DoDiff") { $data = ':degreeOfDifficulty'; }
+ elsif($sortBy eq "S.D.") { $data = ':standardDeviation'; }
+ elsif($sortBy eq "Skew.") { $data = ':skewness'; }
+ elsif($sortBy eq "D.F.1st") { $data = ':discriminationFactor1'; }
+ elsif($sortBy eq "D.F.2nd") { $data = ':discriminationFactor2'; }
+ else { return \@problems; }
+
+ my %temp;
+ my @sequenceList=();
+ foreach(@problems) {
+ my ($sequence) = split(':', $_);
+
+ my @array=();
+ my $tempArray;
+ if(defined($temp{$sequence})) {
+ $tempArray = $temp{$sequence};
+ } else {
+ push(@sequenceList, $sequence);
+ $tempArray = \@array;
+ $temp{$sequence} = $tempArray;
+ }
+
+ push(@$tempArray, $_);
+ }
+
+ my @orderedProblems;
+ if($sortProblems eq "Sort Within Sequence") {
+ foreach(keys(%temp)) {
+ my $tempArray = $temp{$_};
+ my @tempOrder =
+ sort { $problemData->{$a.$data} <=> $problemData->{$b.$data} }
+ @$tempArray;
+ $temp{$_} = \@tempOrder;
+ }
+ foreach(@sequenceList) {
+ my $tempArray = $temp{$_};
+ @orderedProblems = (@orderedProblems, @$tempArray);
+ }
+ } else {
+ @orderedProblems =
+ sort { $problemData->{$a.$data} <=> $problemData->{$b.$data} }
+ @problems;
+ }
+
+ if($ascend eq 'Descending') {
+ @orderedProblems = reverse(@orderedProblems);
+ }
+
+ return \@orderedProblems;
}
-
+sub CalculateStatistics {
+ my ($data, $cache, $courseID)=@_;
-#---- END Problem Statistics Web Page ----------------------------------------
+ my @problems = split(':::', $data->{'problemList'});
+ foreach(@problems) {
+ # Mean
+ my $mean = ($data->{$_.':studentCount'}) ?
+ ($data->{$_.':totalTries'} / $data->{$_.':studentCount'}) : 0;
+ $data->{$_.':mean'} = sprintf("%.2f", $mean);
-#---- Problem Statistics Graph Web Page --------------------------------------
+ # %Wrong
+ my $pw = ($data->{$_.':studentCount'}) ?
+ (($data->{$_.':wrong'} / $data->{$_.':studentCount'}) * 100.0) :
+ 100.0;
+ $data->{$_.':percentWrong'} = sprintf("%.1f", $pw);
-# ------------------------------------------- Prepare data for Graphical chart
+ # Degree of Difficulty
+ my $dod = ($data->{$_.':totalTries'}) ?
+ (1 - (($data->{$_.':correct'} + $data->{$_.':correctByOverride'}) /
+ $data->{$_.':totalTries'})) : 0;
-sub BuildDiffGraph {
- my ($r)=@_;
+ $data->{$_.':degreeOfDifficulty'} = sprintf("%.2f", $dod);
- my $graphData = &GetGraphData('DiffGraph', $r);
- return ' ';
-}
-
-sub BuildWrongGraph {
- my ($r)=@_;
-
- my $graphData = &GetGraphData('WrongGraph', $r);
- return '';
-}
+ # Factor in mean
+ my @studentTries = split(':::', $data->{$_.':studentTries'});
+ foreach(my $index=0; $index < scalar(@studentTries); $index++) {
+ $studentTries[$index] -= $mean;
+ }
+ my $sumSquared = 0;
+ my $sumCubed = 0;
+ foreach(@studentTries) {
+ my $squared = ($_ * $_);
+ my $cubed = ($squared * $_);
+ $sumSquared += $squared;
+ $sumCubed += $cubed;
+ }
+
+ # Standard deviation
+ my $standardDeviation;
+ if($data->{$_.':studentCount'} - 1 > 0) {
+ $standardDeviation = (sqrt($sumSquared)) /
+ ($data->{$_.':studentCount'} - 1);
+ } else {
+ $standardDeviation = 0.0;
+ }
+ $data->{$_.':standardDeviation'} = sprintf("%.1f", $standardDeviation);
+
+ # Skewness
+ my $skew;
+ if($standardDeviation > 0.0999 && $data->{$_.':studentCount'} > 0) {
+ $skew = (((sqrt($sumSquared)) / $data->{$_.':studentCount'}) /
+ ($standardDeviation *
+ $standardDeviation *
+ $standardDeviation));
+ } else {
+ $skew = 0.0;
+ }
+
+ $data->{$_.':skewness'} = sprintf("%.1f", $skew);
+
+ # Discrimination Factor 1
+ my ($sequence, $problem, $part) = split(':', $_);
+
+ my @upper1 = split(':::', $data->{'studentsUpperListCriterion1'});
+ my @lower1 = split(':::', $data->{'studentsLowerListCriterion1'});
+
+ my $upper1Sum=0;
+ foreach my $name (@upper1) {
+ $upper1Sum += $cache->{"$name:$problem:$part:awarded"};
+ }
+ $upper1Sum = (scalar(@upper1)) ? ($upper1Sum/(scalar(@upper1))) : 0;
+
+ my $lower1Sum=0;
+ foreach my $name (@lower1) {
+ $lower1Sum += $cache->{"$name:$problem:$part:awarded"};
+ }
+ $lower1Sum = (scalar(@lower1)) ? ($lower1Sum/(scalar(@lower1))) : 0;
+ my $df1 = $upper1Sum - $lower1Sum;
+ $data->{$_.':discriminationFactor1'} = sprintf("%.2f", $df1);
-sub GetGraphData {
- my ($ylab,$r,%GraphDat)=@_;
- my $Col;
- my $data='';
- my $count = 0;
- my $Max = 0;
- my $cid=$ENV{'request.course.id'};
- my $GraphDB = "/home/httpd/perl/tmp/$ENV{'user.name'}".
- "_$ENV{'user.domain'}_$cid\_graph.db";
- foreach (keys %GraphDat) {delete $GraphDat{$_};}
- if (-e "$GraphDB") {
- if (tie(%GraphDat,'GDBM_File',"$GraphDB",&GDBM_READER,0640)) {
- if ( $ylab eq 'DoDiff Graph' ) {
- $ylab = 'Degree-of-Difficulty';
- $Col = 0;
- }
- else {
- $ylab = 'Wrong-Percentage';
- $Col = 1;
- }
- foreach (sort NumericSort keys %GraphDat) {
- my @Temp=split(/\:/,$GraphDat{$_});
- my $inf = $Temp[$Col];
- if ( $Max < $inf ) {$Max = $inf;}
- $data .= $inf.',';
- $count++;
- }
- if ( $Max > 1 ) {
- $Max += (10 - $Max % 10);
- $Max = int($Max);
- }
- else { $Max = 1; }
- untie(%GraphDat);
- my $Course = $ENV{'course.'.$cid.'.description'};
- $Course =~ s/\ /"_"/eg;
- my $GData=$Course.'&'.'Problems'.'&'.$ylab.'&'.
- $Max.'&'.$count.'&'.$data;
- }
- else {
- $r->print("Unable to tie hash to db file");
- }
+ # Discrimination Factor 2
+ my @upper2 = split(':::', $data->{'studentsUpperListCriterion2'});
+ my @lower2 = split(':::', $data->{'studentsLowerListCriterion2'});
+
+ my $upper2Sum=0;
+ foreach my $name (@upper2) {
+ $upper2Sum += $cache->{"$name:$problem:$part:awarded"};
+ }
+ $upper2Sum = (scalar(@upper2)) ? ($upper2Sum/(scalar(@upper2))) : 0;
+
+ my $lower2Sum=0;
+ foreach my $name (@lower2) {
+ $lower2Sum += $cache->{"$name:$problem:$part:awarded"};
+ }
+ $lower2Sum = (scalar(@lower2)) ? ($lower2Sum/(scalar(@lower2))) : 0;
+
+ my $df2 = $upper2Sum - $lower2Sum;
+ $data->{$_.':discriminationFactor2'} = sprintf("%.2f", $df2);
+
+ my %storestats;
+ my $Average = ($data->{$_.':studentCount'}) ?
+ $data->{$_.':totalTries'}/$data->{$_.':studentCount'} : 0;
+ $storestats{$courseID.'___'.$cache->{$sequence.':source'}.
+ '___timestamp'}=time;
+ $storestats{$courseID.'___'.$cache->{$sequence.':source'}.
+ '___stdno'}=$data->{$_.':studentCount'};
+ $storestats{$courseID.'___'.$cache->{$sequence.':source'}.
+ '___avetries'}=$Average;
+ $storestats{$courseID.'___'.$cache->{$sequence.':source'}.
+ '___difficulty'}=$data->{$_.':degreeOfDifficulty'};
+ $cache->{$sequence.':source'} =~ /^(\w+)\/(\w+)/;
+ if($data->{$_.':studentCount'}) {
+ &Apache::lonnet::put('nohist_resevaldata',\%storestats,$1,$2);
+ }
}
+
+ return;
}
+#---- END Problem Statistics Web Page ----------------------------------------
1;
__END__
|
).
+ ')
');
+ $r->print('