--- loncom/interface/statistics/lonproblemstatistics.pm 2002/08/13 13:57:25 1.21 +++ loncom/interface/statistics/lonproblemstatistics.pm 2002/08/14 20:42:49 1.27 @@ -1,7 +1,7 @@ # The LearningOnline Network with CAPA # (Publication Handler # -# $Id: lonproblemstatistics.pm,v 1.21 2002/08/13 13:57:25 stredwic Exp $ +# $Id: lonproblemstatistics.pm,v 1.27 2002/08/14 20:42:49 stredwic Exp $ # # Copyright Michigan State University Board of Trustees # @@ -45,7 +45,7 @@ use GDBM_File; my $jr; -sub BuildProblemStatisticsPage { +sub InitializeProblemStatistics { my ($cacheDB, $students, $courseID, $c, $r)=@_; my %cache; @@ -53,40 +53,52 @@ sub BuildProblemStatisticsPage { unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) { $r->print('Unable to tie database.'); - return; + return ('ERROR', undef); } - my $Ptr = ''; - $Ptr .= ''; - $Ptr .= ''."\n"; - $Ptr .= ''."\n"; - $Ptr .= ''."\n"; - $Ptr .= ''."\n"; - $Ptr .= &ProblemStatisticsButtons($cache{'DisplayFormat'}, - $cache{'DisplayLegend'}); - $Ptr .= '
Select Map'; - $Ptr .= &Apache::lonhtmlcommon::MapOptions(\%cache, 'ProblemStatistics', - 'Statistics'); - $Ptr .= '
Sorting Type:'."\n"; - $Ptr .= &Apache::lonhtmlcommon::AscendOrderOptions( - $cache{'ProblemStatisticsAscend'}, - 'ProblemStatistics', - 'Statistics'); - $Ptr .= '
'; - if($cache{'DisplayLegend'} eq 'Show Legend') { - $Ptr .= &ProblemStatisticsLegend(); + # Remove students who don't have the proper section. + my @sectionsSelected = split(':',$cache{'sectionsSelected'}); + for(my $studentIndex=((scalar @$students)-1); $studentIndex>=0; + $studentIndex--) { + my $value = $cache{$students->[$studentIndex].':section'}; + my $found = 0; + foreach (@sectionsSelected) { + if($_ eq 'none') { + if($value eq '' || !defined($value) || $value eq ' ') { + $found = 1; + last; + } + } else { + if($value eq $_) { + $found = 1; + last; + } + } + } + if($found == 0) { + splice(@$students, $studentIndex, 1); + } } - $r->print($Ptr); - $r->rflush(); - my @Header = ("Homework Sets Order","#Stdnts","Tries","Mod", - "Mean","#YES","#yes","%Wrng","DoDiff", - "S.D.","Skew.","D.F.1st","D.F.2nd","Disc."); - my $color=&setbgcolor(0); - -# my %Discuss=&Apache::loncoursedata::LoadDiscussion($courseID); -# my ($upper, $lower) = &Discriminant(\%discriminant,$r); - if(!defined($cache{'StatisticsCached'})) { + my $lastStatus = (defined($cache{'StatisticsLastStatus'})) ? + $cache{'StatisticsLastStatus'} : 'Nothing'; + my $whichStudents = join(':::',sort(@$students)); + if(!defined($cache{'StatisticsCached'}) || + $lastStatus ne $cache{'Status'} || + $whichStudents ne $cache{'StatisticsWhichStudents'}) { + if(defined($cache{'StatisticsCached'})) { + untie(%cache); + unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_WRCREAT(),0640)) { + $r->print('Unable to tie database.'); + return ('ERROR', undef); + } + my @statkeys = split(':::', $cache{'StatisticsKeys'}); + delete $cache{'StatisticsKeys'}; + delete $cache{'StatisticsCached'}; + foreach(@statkeys) { + delete $cache{$_}; + } + } untie(%cache); &Apache::loncoursedata::DownloadStudentCourseDataSeparate($students, 'true', @@ -95,41 +107,157 @@ sub BuildProblemStatisticsPage { 'true', $courseID, $r, $c); - if($c->aborted()) { return; } + if($c->aborted()) { return ('ERROR', undef); } unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) { $r->print('Unable to tie database.'); - return; + return ('ERROR', undef); } my ($problemData) = &ExtractStudentData(\%cache, $students); - &CalculateStatistics($problemData); + &CalculateStatistics($problemData, \%cache); untie(%cache); unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_WRCREAT(),0640)) { $r->print('Unable to tie database.'); - return; + return ('ERROR', undef); } foreach(keys(%$problemData)) { $cache{$_} = $problemData->{$_}; } + $cache{'StatisticsKeys'} = join(':::', keys(%$problemData)); $cache{'StatisticsCached'} = 'true'; + $cache{'StatisticsLastStatus'} = $cache{'Status'}; + $cache{'StatisticsWhichStudents'} = $whichStudents; untie(%cache); unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) { $r->print('Unable to tie database.'); - return; + return ('ERROR', undef); } } + my $orderedProblems = &SortProblems(\%cache, $cache{'ProblemStatisticsSort'}, + $cache{'SortProblems'}, $cache{'ProblemStatisticsAscend'}); - &BuildStatisticsTable(\%cache, $cache{'DisplayFormat'}, $orderedProblems, + return ('OK', $orderedProblems); +} + +sub BuildProblemStatisticsPage { + my ($cacheDB, $students, $courseID, $c, $r)=@_; + + my @Header = ("Homework Sets Order","#Stdnts","Tries","Mod", + "Mean","#YES","#yes","%Wrng","DoDiff", + "S.D.","Skew.","D.F.1st","D.F.2nd"); + my $color=&setbgcolor(0); + my %cache; + + unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) { + $r->print('Unable to tie database.'); + return; + } + my $Ptr = ''; + $Ptr .= ''; + $Ptr .= ''."\n"; + $Ptr .= ''."\n"; + $Ptr .= ''."\n"; + $Ptr .= ''."\n"; + $Ptr .= ''."\n"; + $Ptr .= ''."\n"; + $Ptr .= &ProblemStatisticsButtons($cache{'DisplayFormat'}, + $cache{'DisplayLegend'}, + $cache{'SortProblems'}); + $Ptr .= '
Select Map'; + $Ptr .= &Apache::lonhtmlcommon::MapOptions(\%cache, 'ProblemStatistics', + 'Statistics'); + $Ptr .= '
Sorting Type:'."\n"; + $Ptr .= &Apache::lonhtmlcommon::AscendOrderOptions( + $cache{'ProblemStatisticsAscend'}, + 'ProblemStatistics', + 'Statistics'); + $Ptr .= '
Select Sections'; + $Ptr .= ''."\n"; + my @sections = split(':',$cache{'sectionList'}); + my @sectionsSelected = split(':',$cache{'sectionsSelected'}); + $Ptr .= &Apache::lonhtmlcommon::MultipleSectionSelect(\@sections, + \@sectionsSelected, + 'Statistics'); + $Ptr .= '
'; + if($cache{'DisplayLegend'} eq 'Show Legend') { + $Ptr .= &ProblemStatisticsLegend(); + } + $r->print($Ptr); + $r->rflush(); + untie(%cache); + + my ($result, $orderedProblems) = + &InitializeProblemStatistics($cacheDB, $students, $courseID, $c, $r); + if($result ne 'OK') { + return; + } + + unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) { + $r->print('Unable to tie database.'); + return; + } + &BuildStatisticsTable(\%cache, $cache{'DisplayFormat'}, + $cache{'SortProblems'}, $orderedProblems, \@Header, $r, $color); untie(%cache); return; } +sub BuildGraphicChart { + my ($graph,$cacheDB,$courseDescription,$students,$courseID,$r,$c)=@_; + my %cache; + my $max = 0; + + my ($result, undef) = + &InitializeProblemStatistics($cacheDB, $students, $courseID, $c, $r); + if($result ne 'OK') { + return; + } + + unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) { + return 'Unable to tie database.'; + } + + my @problems = split(':::', $cache{'problemList'}); + my @values = (); + foreach (@problems) { + my $data = 0; + if($graph eq 'DoDiffGraph') { + $data = sprintf("%.2f", $cache{$_.':degreeOfDifficulty'}), + } else { + $data = sprintf("%.1f", $cache{$_.':percentWrong'}), + } + if($max < $data) { + $max = $data; + } + push(@values, $data); + } + untie(%cache); + + my $sendValues = join(',', @values); + my $sendCount = scalar(@values); + + my $title = ''; + if($graph eq 'DoDiffGraph') { + $title = 'Degree-of-Difficulty'; + } else { + $title = 'Wrong-Percentage'; + } + my @GData = ($courseDescription, 'Problems', $title, $max, $sendCount, + $sendValues); + + $r->print(''."\n"); + $r->print(''); + $r->print('
'."\n"); + + return; +} #---- Problem Statistics Web Page --------------------------------------- @@ -140,7 +268,8 @@ sub CreateProblemStatisticsTableHeading $Str .= ''."\n"; $Str .= 'P#'."\n"; foreach(@$headings) { - $Str .= ''.''; + $Str .= ''.$_.' '."\n"; @@ -151,127 +280,117 @@ sub CreateProblemStatisticsTableHeading } sub BuildStatisticsTable { - my ($cache,$displayFormat,$orderedProblems,$headings,$r,$color)=@_; - -#6666666 -# my $file="/home/httpd/perl/tmp/183d.txt"; -# open(OUT, ">$file"); -#6666666 -## &Apache::lonstatistics::Create_PrgWin($r); -##777777 -## my (%Activity) = &LoadActivityLog(); -## $r->print(''); -## my ($doDiffFile) = &LoadDoDiffFile(); - -##777777 -## $Str .= &Classify($discriminantFactor, $students); - - if($displayFormat ne 'Display CSV Format') { - $r->print('
'."\n"); - $r->print(''."\n"); - $r->print(&CreateProblemStatisticsTableHeading($headings, $r)); - } else { - $r->print('
'); - } + my ($cache,$displayFormat,$sortProblems,$orderedProblems,$headings, + $r,$color)=@_; my $count = 1; + my $currentSequence = -1; foreach(@$orderedProblems) { my ($sequence,$problem,$part)=split(':', $_); -# if($cache->{'ProblemStatisticsMaps'} ne 'All Maps' && -# $cache->{'ProblemStatisticsMaps'} ne $cache->{$sequence.':title'}) { -# next; -# } + if($cache->{'StatisticsMaps'} ne 'All Maps' && + $cache->{'StatisticsMaps'} ne $cache->{$sequence.':title'}) { + next; + } + if($currentSequence == -1 || + ($sortProblems eq 'Sort Within Sequence' && + $currentSequence != $sequence)) { + if($displayFormat ne 'Display CSV Format') { + if($currentSequence ne -1) { + $r->print('
'); + $r->print('

'); + } + if($sortProblems eq 'Sort Within Sequence') { + $r->print(''.$cache->{$sequence.':title'}.''); + } + $r->print('
'."\n"); + $r->print(''."\n"); + $r->print(&CreateProblemStatisticsTableHeading($headings, $r)); + } else { + if($sortProblems eq 'Sort Within Sequence') { + $r->print('"'.$cache->{$sequence.':title'}.'"'); + } + $r->print('
'); + } + $currentSequence = $sequence; + } my $ref = ''.$cache->{$problem.':title'}.''; -# my $ref = $cache->{$problem.':title'}; my $title = $cache->{$problem.':title'}; - my $source = 'source'; + if($part != 0) { + $title .= ' Part '.$part; + } + my $source = $cache->{$problem.':source'}; my $tableData = join('&', $ref, $title, $source, $cache->{$_.':studentCount'}, $cache->{$_.':totalTries'}, $cache->{$_.':maxTries'}, - sprintf("%.2f", $cache->{$_.':mean'}), + $cache->{$_.':mean'}, $cache->{$_.':correct'}, $cache->{$_.':correctByOverride'}, - sprintf("%.1f", $cache->{$_.':percentWrong'}), - sprintf("%.2f", $cache->{$_.':degreeOfDifficulty'}), - sprintf("%.1f", $cache->{$_.':standardDeviation'}), - sprintf("%.1f", $cache->{$_.':skewness'}), - sprintf("%.2f", $cache->{$_.':discriminationFactor1'}), - sprintf("%.2f", $cache->{$_.':discriminationFactor2'}), - 0); # 0 is for discussion, need to figure out - -#6666666 -# $r->print('
'.$out.'&'.$DoD); -# print (OUT $out.'@'.$DoD.'&'); -#6666666 - -#check with Gerd -# $urlres=~/^(\w+)\/(\w+)/; -# if ($StdNo) { -# &Apache::lonnet::put('nohist_resevaldata',\%storestats, -# $1,$2); -# } -#-------------------------------- Row of statistical table + $cache->{$_.':percentWrong'}, + $cache->{$_.':degreeOfDifficulty'}, + $cache->{$_.':standardDeviation'}, + $cache->{$_.':skewness'}, + $cache->{$_.':discriminationFactor1'}, + $cache->{$_.':discriminationFactor2'}); + &TableRow($displayFormat,$tableData,$count,$r,$color); + $count++; } - if($cache->{'DisplayFormat'} ne 'Display CSV Format') { + if($displayFormat ne 'Display CSV Format') { $r->print('
'."\n"); + $r->print('
'); + } else { + $r->print('
'); } - $r->print(''); -#6666666 -# close( OUT ); -#666666 + return; } sub TableRow { my ($displayFormat,$Str,$RealIdx,$r,$color)=@_; my($ref,$title,$source,$StdNo,$TotalTries,$MxTries,$Avg,$YES,$Override, - $Wrng,$DoD,$SD,$Sk,$_D1,$_D2,$DiscNo,$Prob)=split(/\&/,$Str); + $Wrng,$DoD,$SD,$Sk,$_D1,$_D2)=split(/\&/,$Str); my $Ptr; if($displayFormat eq 'Display CSV Format') { - $Ptr="\n".'
'. - "\n".'"'.$RealIdx.'",'. - "\n".'"'.$title.'",'. - "\n".'"'.$source.'",'. - "\n".'"'.$StdNo.'",'. - "\n".'"'.$TotalTries.'",'. - "\n".'"'.$MxTries.'",'. - "\n".'"'.$Avg.'",'. - "\n".'"'.$YES.'",'. - "\n".'"'.$Override.'",'. - "\n".'"'.$Wrng.'",'. - "\n".'"'.$DoD.'",'. - "\n".'"'.$SD.'",'. - "\n".'"'.$Sk.'",'. - "\n".'"'.$_D1.'",'. - "\n".'"'.$_D2.'"'. - "\n".'"'.$DiscNo.'"'; + $Ptr='"'.$RealIdx.'",'."\n". + '"'.$title.'",'."\n". + '"'.$source.'",'."\n". + '"'.$StdNo.'",'."\n". + '"'.$TotalTries.'",'."\n". + '"'.$MxTries.'",'."\n". + '"'.$Avg.'",'."\n". + '"'.$YES.'",'."\n". + '"'.$Override.'",'."\n". + '"'.$Wrng.'",'."\n". + '"'.$DoD.'",'."\n". + '"'.$SD.'",'."\n". + '"'.$Sk.'",'."\n". + '"'.$_D1.'",'."\n". + '"'.$_D2.'"'."\n". + "
\n"; $r->print("\n".$Ptr); } else { - $Ptr="\n".''. - "\n".''.$RealIdx.''. - "\n".''.$ref.''. - "\n".' '.$StdNo.''. - "\n".''.$TotalTries.''. - "\n".''.$MxTries.''. - "\n".''.$Avg.''. - "\n".' '.$YES.''. - "\n".' '.$Override.''. - "\n".' '.$Wrng.''. - "\n".' '.$DoD.''. - "\n".' '.$SD.''. - "\n".' '.$Sk.''. - "\n".' '.$_D1.''. - "\n".' '.$_D2.''. - "\n".' '.$DiscNo.''; - $r->print("\n".$Ptr.'' ); + $Ptr=''."\n". + ''.$RealIdx.''."\n". + ''.$ref.''."\n". + ' '.$StdNo.''."\n". + ''.$TotalTries.''."\n". + ''.$MxTries.''."\n". + ''.$Avg.''."\n". + ' '.$YES.''."\n". + ' '.$Override.''."\n". + ' '.$Wrng.''."\n". + ' '.$DoD.''."\n". + ' '.$SD.''."\n". + ' '.$Sk.''."\n". + ' '.$_D1.''."\n". + ' '.$_D2.''."\n"; + $r->print($Ptr.''."\n"); } return; @@ -299,22 +418,29 @@ sub setbgcolor { } sub ProblemStatisticsButtons { - my ($displayFormat, $displayLegend)=@_; + my ($displayFormat, $displayLegend, $sortProblems)=@_; my $Ptr = ''; $Ptr .= '{'orderedSequences'})) { @@ -437,11 +557,12 @@ sub ExtractStudentData { } } + my $studentTriesJoined = join(':::', @studentTries); $problemData{$id.':sequenceTitle'} = $cache->{$sequence.':title'}; $problemData{$id.':studentCount'} = $studentCount; $problemData{$id.':totalTries'} = $totalTries; - $problemData{$id.':studentTries'} = \@studentTries; + $problemData{$id.':studentTries'} = $studentTriesJoined; $problemData{$id.':totalAwarded'} = $totalAwarded; $problemData{$id.':correct'} = $correct; $problemData{$id.':correctByOverride'} = $correctByOverride; @@ -453,18 +574,51 @@ sub ExtractStudentData { } } + 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); -# $Discussed=0; -# if($Discuss->{"$name:$problem"}) { -# $TotDiscuss++; -# $Discussed=1; -# } return \%problemData; } +sub SortDivideByTries { + my ($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,$ascend)=@_; + my ($problemData,$sortBy,$sortProblems,$ascend)=@_; my @problems = split(':::', $problemData->{'problemList'}); if($sortBy eq "Homework Sets Order") { @@ -483,14 +637,47 @@ sub SortProblems { 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") { $data = ':discriminantFactor1'; } - elsif($sortBy eq "D.F.2nd") { $data = ':discriminantFactor2'; } - elsif($sortBy eq "Disc.") { $data = ''; } + elsif($sortBy eq "D.F.1st") { $data = ':discriminationFactor1'; } + elsif($sortBy eq "D.F.2nd") { $data = ':discriminationFactor2'; } else { return \@problems; } - my @orderedProblems = - sort { $problemData->{$a.$data} <=> $problemData->{$b.$data} } - @problems; + my %temp; + my @sequenceList=(); + foreach(@problems) { + my ($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); } @@ -499,32 +686,36 @@ sub SortProblems { } sub CalculateStatistics { - my ($data)=@_; + my ($data, $cache)=@_; my @problems = split(':::', $data->{'problemList'}); foreach(@problems) { # Mean - $data->{$_.':mean'} = ($data->{$_.':studentCount'}) ? + my $mean = ($data->{$_.':studentCount'}) ? ($data->{$_.':totalTries'} / $data->{$_.':studentCount'}) : 0; + $data->{$_.':mean'} = sprintf("%.2f", $mean); # %Wrong - $data->{$_.':percentWrong'} = ($data->{$_.':studentCount'}) ? + my $pw = ($data->{$_.':studentCount'}) ? (($data->{$_.':wrong'} / $data->{$_.':studentCount'}) * 100.0) : 100.0; + $data->{$_.':percentWrong'} = sprintf("%.1f", $pw); # Degree of Difficulty - $data->{$_.':degreeOfDifficulty'} = ($data->{$_.':totalTries'}) ? + my $dod = ($data->{$_.':totalTries'}) ? (1 - (($data->{$_.':correct'} + $data->{$_.':correctByOverride'}) / $data->{$_.':totalTries'})) : 0; + $data->{$_.':degreeOfDifficulty'} = sprintf("%.2f", $dod); + # Factor in mean - my $studentTries = $data->{$_.':studentTries'}; - foreach(my $index=0; $index < scalar(@$studentTries); $index++) { - $studentTries->[$index] -= $data->{$_.':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) { + foreach(@studentTries) { my $squared = ($_ * $_); my $cubed = ($squared * $_); $sumSquared += $squared; @@ -532,147 +723,73 @@ sub CalculateStatistics { } # Standard deviation - $data->{$_.':standardDeviation'} = ($data->{$_.':studentCount'} - 1) ? - ((sqrt($sumSquared)) / ($data->{$_.':studentCount'} - 1)) : 0; + my $standardDeviation; + if($data->{$_.':studentCount'} - 1 > 0) { + $standardDeviation = (sqrt($sumSquared)) / + ($data->{$_.':studentCount'} - 1); + } else { + $standardDeviation = 0.0; + } + $data->{$_.':standardDeviation'} = sprintf("%.1f", $standardDeviation); # Skewness - my $standardDeviation = $data->{$_.':standardDeviation'}; - $data->{$_.':skewness'} = ($data->{$_.':standardDeviation'}) ? - (((sqrt($sumSquared)) / $data->{$_.':studentCount'}) / - ($standardDeviation * $standardDeviation * $standardDeviation)) : - 0; + my $skew; + if($standardDeviation > 0.0999 && $data->{$_.':studentCount'} > 0) { + $skew = (((sqrt($sumSquared)) / $data->{$_.':studentCount'}) / + ($standardDeviation * + $standardDeviation * + $standardDeviation)); + } else { + $skew = 0.0; + } - # Discrimination Factor 1 - $data->{$_.':discriminationFactor1'} = 0; + $data->{$_.':skewness'} = sprintf("%.1f", $skew); - # Discrimination Factor 2 - $data->{$_.':discriminationFactor2'} = 0; - } + # Discrimination Factor 1 + my ($sequence, $problem, $part) = split(':', $_); - return; -} + my @upper1 = split(':::', $data->{'studentsUpperListCriterion1'}); + my @lower1 = split(':::', $data->{'studentsLowerListCriterion1'}); -sub ProcessDiscriminant { - my ($List) = @_; - my @sortedList = sort (@$List); - my $Count = scalar @sortedList; - my $Problem; - my @Dis; - my $Slvd=0; - my $tmp; - my $Sum1=0; - my $Sum2=0; - my $nIndex=0; - my $nStudent=0; - my %Proc=undef; - while ($nIndex<$Count) { -# $jr->print("
$nIndex) $sortedList[$nIndex]"); - ($Problem,$tmp)=split(/\=/,$sortedList[$nIndex]); - @Dis=split(/\+/,$tmp); - my $Temp = $Problem; - do { - $nIndex++; - $nStudent++; - $Sum1 += $Dis[0]; - $Sum2 += $Dis[1]; - ($Problem,$tmp)=split(/\=/,$sortedList[$nIndex]); - @Dis=split(/\+/,$tmp); - } while ( $Problem eq $Temp && $nIndex < $Count ); - $Proc{$Temp}=($Sum1/$nStudent).':'.($Sum2/$nStudent); -# $jr->print("
$nIndex) $Temp --> ($nStudent) $Proc{$Temp}"); - $Sum1=0; - $Sum2=0; - $nStudent=0; - } - - return %Proc; -} - -#------- Creating Discimination factor -sub Discriminant { - my ($discriminant)=@_; - my @discriminantKeys=keys(%$discriminant); - 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 $str=$discriminant->{$key}; - foreach(split(/\&/,$str)){ - if($_) { - if($low<$UpCnt) { push(@LowList,$_); } - else { push(@UpList,$_); } - } - } + my $upper1Sum=0; + foreach my $name (@upper1) { + $upper1Sum += $cache->{"$name:$problem:$part:awarded"}; } - } - my %DisUp = &ProcessDiscriminant(\@UpList); - my %DisLow = &ProcessDiscriminant(\@LowList); - - return (\%DisUp, \%DisLow); -} - -#---- END Problem Statistics Web Page ---------------------------------------- + $upper1Sum = (scalar(@upper1)) ? ($upper1Sum/(scalar(@upper1))) : 0; -#---- Problem Statistics Graph Web Page -------------------------------------- + my $lower1Sum=0; + foreach my $name (@lower1) { + $lower1Sum += $cache->{"$name:$problem:$part:awarded"}; + } + $lower1Sum = (scalar(@lower1)) ? ($lower1Sum/(scalar(@lower1))) : 0; -# ------------------------------------------- Prepare data for Graphical chart + my $df1 = $upper1Sum - $lower1Sum; + $data->{$_.':discriminationFactor1'} = sprintf("%.2f", $df1); -sub BuildGraphicChart { - my ($ylab,$r,$cacheDB)=@_; - my %cache; - my $Col; - my $data=''; - my $count = 0; - my $Max = 0; + # Discrimination Factor 2 + my @upper2 = split(':::', $data->{'studentsUpperListCriterion2'}); + my @lower2 = split(':::', $data->{'studentsLowerListCriterion2'}); - unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) { - return 'Unable to tie database.'; - } - - my $p_count = $cache{'ProblemCount'}; + my $upper2Sum=0; + foreach my $name (@upper2) { + $upper2Sum += $cache->{"$name:$problem:$part:awarded"}; + } + $upper2Sum = (scalar(@upper2)) ? ($upper2Sum/(scalar(@upper2))) : 0; - for ( my $k=0; $k<$p_count;$k++) { - my @Temp=split(/\:/,$cache{'GraphGif:'.$k}); - my $inf = $Temp[$Col]; - if ( $Max < $inf ) {$Max = $inf;} - $data .= $inf.','; - $count++; - } - untie(%cache); -# $r->print("
count=$p_count >>data= $data"); + my $lower2Sum=0; + foreach my $name (@lower2) { + $lower2Sum += $cache->{"$name:$problem:$part:awarded"}; + } + $lower2Sum = (scalar(@lower2)) ? ($lower2Sum/(scalar(@lower2))) : 0; - if ( $Max > 1 ) { - $Max += (10 - $Max % 10); - $Max = int($Max); - } else { $Max = 1; } - - my $cid=$ENV{'request.course.id'}; - - if ( $ylab eq 'DoDiff Graph' ) { - $ylab = 'Degree-of-Difficulty'; - $Col = 0; - } else { - $ylab = 'Wrong-Percentage'; - $Col = 1; + my $df2 = $upper2Sum - $lower2Sum; + $data->{$_.':discriminationFactor2'} = sprintf("%.2f", $df2); } - my $Course = $ENV{'course.'.$cid.'.description'}; - $Course =~ s/\ /"_"/eg; - my $GData=$Course.'&'.'Problems#'.'&'.$ylab.'&'. - $Max.'&'.$count.'&'.$data; - - $r->print(''); return; } +#---- END Problem Statistics Web Page ---------------------------------------- + 1; __END__