AutorÃa | Ultima modificación | Ver Log |
<?php// This file is part of Moodle - http://moodle.org///// Moodle is free software: you can redistribute it and/or modify// it under the terms of the GNU General Public License as published by// the Free Software Foundation, either version 3 of the License, or// (at your option) any later version.//// Moodle is distributed in the hope that it will be useful,// but WITHOUT ANY WARRANTY; without even the implied warranty of// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the// GNU General Public License for more details.//// You should have received a copy of the GNU General Public License// along with Moodle. If not, see <http://www.gnu.org/licenses/>./*** Quiz statistics report, table for showing statistics of each question in the quiz.** @package quiz_statistics* @copyright 2008 Jamie Pratt* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later*/defined('MOODLE_INTERNAL') || die();require_once($CFG->libdir.'/tablelib.php');use \core_question\statistics\questions\calculated_question_summary;/*** This table has one row for each question in the quiz, with sub-rows when* random questions and variants appear.** There are columns for the various item and position statistics.** @copyright 2008 Jamie Pratt* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later*/class quiz_statistics_table extends flexible_table {/** @var stdClass the quiz settings. */protected $quiz;/** @var integer the quiz course_module id. */protected $cmid;/*** Constructor.*/public function __construct() {parent::__construct('mod-quiz-report-statistics-report');}/*** Set up the columns and headers and other properties of the table and then* call flexible_table::setup() method.** @param stdClass $quiz the quiz settings* @param int $cmid the quiz course_module id* @param moodle_url $reporturl the URL to redisplay this report.* @param int $s number of attempts included in the statistics.*/public function statistics_setup($quiz, $cmid, $reporturl, $s) {$this->quiz = $quiz;$this->cmid = $cmid;// Define the table columns.$columns = [];$headers = [];$columns[] = 'number';$headers[] = get_string('questionnumber', 'quiz_statistics');if (!$this->is_downloading()) {$columns[] = 'icon';$headers[] = '';$columns[] = 'actions';$headers[] = '';} else {$columns[] = 'qtype';$headers[] = get_string('questiontype', 'quiz_statistics');}$columns[] = 'name';$headers[] = get_string('questionname', 'quiz');$columns[] = 's';$headers[] = get_string('attempts', 'quiz_statistics');if ($s > 1) {$columns[] = 'facility';$headers[] = get_string('facility', 'quiz_statistics');$columns[] = 'sd';$headers[] = get_string('standarddeviationq', 'quiz_statistics');}$columns[] = 'random_guess_score';$headers[] = get_string('random_guess_score', 'quiz_statistics');$columns[] = 'intended_weight';$headers[] = get_string('intended_weight', 'quiz_statistics');$columns[] = 'effective_weight';$headers[] = get_string('effective_weight', 'quiz_statistics');$columns[] = 'discrimination_index';$headers[] = get_string('discrimination_index', 'quiz_statistics');$columns[] = 'discriminative_efficiency';$headers[] = get_string('discriminative_efficiency', 'quiz_statistics');$this->define_columns($columns);$this->define_headers($headers);$this->sortable(false);$this->column_class('s', 'numcol');$this->column_class('facility', 'numcol');$this->column_class('sd', 'numcol');$this->column_class('random_guess_score', 'numcol');$this->column_class('intended_weight', 'numcol');$this->column_class('effective_weight', 'numcol');$this->column_class('discrimination_index', 'numcol');$this->column_class('discriminative_efficiency', 'numcol');// Set up the table.$this->define_baseurl($reporturl->out());$this->collapsible(true);$this->set_attribute('id', 'questionstatistics');$this->set_attribute('class', 'generaltable generalbox boxaligncenter');parent::setup();}/*** Open a div tag to wrap statistics table.*/public function wrap_html_start() {// Horrible Moodle 2.0 wide-content work-around.if (!$this->is_downloading()) {echo html_writer::start_tag('div', ['id' => 'tablecontainer','class' => 'statistics-tablecontainer']);}}/*** Close a statistics table div.*/public function wrap_html_finish() {if (!$this->is_downloading()) {echo html_writer::end_tag('div');}}/*** The question number.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_number($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {return '';}if (!isset($questionstat->question->number)) {return '';}$number = $questionstat->question->number;if (isset($questionstat->subqdisplayorder)) {$number = $number . '.'.$questionstat->subqdisplayorder;}if ($questionstat->question->qtype != 'random' && !is_null($questionstat->variant)) {$number = $number . '.'.$questionstat->variant;}return $number;}/*** The question type icon.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_icon($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {return '';} else {$questionobject = $questionstat->question;return print_question_icon($questionobject);}}/*** Actions that can be performed on the question by this user (e.g. edit or preview).* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_actions($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {return '';} else if ($questionstat->question->qtype === 'missingtype') {return '';} else {return quiz_question_action_icons($this->quiz, $this->cmid,$questionstat->question, $this->baseurl, $questionstat->variant);}}/*** The question type name.** @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_qtype($questionstat) {return question_bank::get_qtype_name($questionstat->question->qtype);}/*** The question name.** @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_name($questionstat) {$name = $questionstat->question->name;if (!is_null($questionstat->variant)) {$a = new stdClass();$a->name = $name;$a->variant = $questionstat->variant;$name = get_string('nameforvariant', 'quiz_statistics', $a);}if ($this->is_downloading()) {return $name;}$baseurl = new moodle_url($this->baseurl);if (!is_null($questionstat->variant)) {if ($questionstat->subquestion) {// Variant of a sub-question.$url = new moodle_url($baseurl, ['qid' => $questionstat->questionid, 'variant' => $questionstat->variant]);$name = html_writer::link($url, $name, ['title' => get_string('detailedanalysisforvariant','quiz_statistics',$questionstat->variant)]);} else if ($questionstat->slot) {// Variant of a question in a slot.$url = new moodle_url($baseurl, ['slot' => $questionstat->slot, 'variant' => $questionstat->variant]);$name = html_writer::link($url, $name, ['title' => get_string('detailedanalysisforvariant','quiz_statistics',$questionstat->variant)]);}} else {if ($questionstat->subquestion && !$questionstat->get_variants()) {// Sub question without variants.$url = new moodle_url($baseurl, ['qid' => $questionstat->questionid]);$name = html_writer::link($url, $name, ['title' => get_string('detailedanalysis', 'quiz_statistics')]);} else if ($baseurl->param('slot') === null && $questionstat->slot) {// Question in a slot, we are not on a page showing structural analysis of one slot,// we don't want linking on those pages.$number = $questionstat->question->number;$israndomquestion = $questionstat->question->qtype == 'random';$url = new moodle_url($baseurl, ['slot' => $questionstat->slot]);if ($this->is_calculated_question_summary($questionstat)) {// Only make the random question summary row name link to the slot structure// analysis page with specific text to clearly indicate the link to the user.// Random and variant question rows will render the name without a link to improve clarity// in the UI.$name = html_writer::div(get_string('rangeofvalues', 'quiz_statistics'));} else if (!$israndomquestion && !$questionstat->get_variants() && !$questionstat->get_sub_question_ids()) {// Question cannot be broken down into sub-questions or variants. Link will show response analysis page.$name = html_writer::link($url,$name,['title' => get_string('detailedanalysis', 'quiz_statistics')]);}}}if ($this->is_dubious_question($questionstat)) {$name = html_writer::tag('div', $name, ['class' => 'dubious']);}if ($this->is_calculated_question_summary($questionstat)) {$name .= html_writer::link($url, get_string('viewanalysis', 'quiz_statistics'));} else if (!empty($questionstat->minmedianmaxnotice)) {$name = get_string($questionstat->minmedianmaxnotice, 'quiz_statistics') . '<br />' . $name;}return $name;}/*** The number of attempts at this question.** @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_s($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('s');$min = $min ?: 0;$max = $max ?: 0;return $this->format_range($min, $max);} else if (!isset($questionstat->s)) {return 0;} else {return $questionstat->s;}}/*** The facility index (average fraction).* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_facility($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('facility');return $this->format_percentage_range($min, $max);} else if (is_null($questionstat->facility)) {return '';} else {return $this->format_percentage($questionstat->facility);}}/*** The standard deviation of the fractions.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_sd($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('sd');return $this->format_percentage_range($min, $max);} else if (is_null($questionstat->sd) || $questionstat->maxmark == 0) {return '';} else {return $this->format_percentage($questionstat->sd / $questionstat->maxmark);}}/*** An estimate of the fraction a student would get by guessing randomly.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_random_guess_score($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('randomguessscore');return $this->format_percentage_range($min, $max);} else if (is_null($questionstat->randomguessscore)) {return '';} else {return $this->format_percentage($questionstat->randomguessscore);}}/*** The intended question weight. Maximum mark for the question as a percentage* of maximum mark for the quiz. That is, the indended influence this question* on the student's overall mark.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_intended_weight($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('maxmark');if (is_null($min) && is_null($max)) {return '';} else {$min = quiz_report_scale_summarks_as_percentage($min, $this->quiz);$max = quiz_report_scale_summarks_as_percentage($max, $this->quiz);return $this->format_range($min, $max);}} else {return quiz_report_scale_summarks_as_percentage($questionstat->maxmark, $this->quiz);}}/*** The effective question weight. That is, an estimate of the actual* influence this question has on the student's overall mark.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_effective_weight($questionstat) {global $OUTPUT;if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('effectiveweight');if (is_null($min) && is_null($max)) {return '';} else {list( , $negcovar) = $questionstat->get_min_max_of('negcovar');if ($negcovar) {$min = get_string('negcovar', 'quiz_statistics');}return $this->format_range($min, $max);}} else if (is_null($questionstat->effectiveweight)) {return '';} else if ($questionstat->negcovar) {$negcovar = get_string('negcovar', 'quiz_statistics');if (!$this->is_downloading()) {$negcovar = html_writer::tag('div',$negcovar . $OUTPUT->help_icon('negcovar', 'quiz_statistics'),['class' => 'negcovar']);}return $negcovar;} else {return $this->format_percentage($questionstat->effectiveweight, false);}}/*** Discrimination index. This is the product moment correlation coefficient* between the fraction for this question, and the average fraction for the* other questions in this quiz.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_discrimination_index($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('discriminationindex');if (isset($max)) {$min = $min ?: 0;}if (is_numeric($min)) {$min = $this->format_percentage($min, false);}if (is_numeric($max)) {$max = $this->format_percentage($max, false);}return $this->format_range($min, $max);} else if (!is_numeric($questionstat->discriminationindex)) {return $questionstat->discriminationindex;} else {return $this->format_percentage($questionstat->discriminationindex, false);}}/*** Discrimination efficiency, similar to, but different from, the Discrimination index.** @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return string contents of this table cell.*/protected function col_discriminative_efficiency($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {list($min, $max) = $questionstat->get_min_max_of('discriminativeefficiency');if (!is_numeric($min) && !is_numeric($max)) {return '';} else {return $this->format_percentage_range($min, $max, false);}} else if (!is_numeric($questionstat->discriminativeefficiency)) {return '';} else {return $this->format_percentage($questionstat->discriminativeefficiency, false);}}/*** This method encapsulates the test for wheter a question should be considered dubious.* @param \core_question\statistics\questions\calculated $questionstat stats for the question.* @return bool is this question possibly not pulling it's weight?*/protected function is_dubious_question($questionstat) {if ($this->is_calculated_question_summary($questionstat)) {// We only care about the minimum value here.// If the minimum value is less than the threshold, then we know that there is at least one value below the threshold.list($discriminativeefficiency) = $questionstat->get_min_max_of('discriminativeefficiency');} else {$discriminativeefficiency = $questionstat->discriminativeefficiency;}if (!is_numeric($discriminativeefficiency)) {return false;}return $discriminativeefficiency < 15;}/*** Check if the given stats object is an instance of calculated_question_summary.** @param \core_question\statistics\questions\calculated $questionstat Stats object* @return bool*/protected function is_calculated_question_summary($questionstat) {return $questionstat instanceof calculated_question_summary;}/*** Format inputs to represent a range between $min and $max.* This function does not check if $min is less than $max or not.* If both $min and $max are equal to null, this function returns an empty string.** @param string|null $min The minimum value in the range* @param string|null $max The maximum value in the range* @return string*/protected function format_range(string $min = null, string $max = null) {if (is_null($min) && is_null($max)) {return '';} else {$a = new stdClass();$a->min = $min;$a->max = $max;return get_string('rangebetween', 'quiz_statistics', $a);}}/*** Format a number to a localised percentage with specified decimal points.** @param float $number The number being formatted* @param bool $fraction An indicator for whether the number is a fraction or is already multiplied by 100* @param int $decimals Sets the number of decimal points* @return string*/protected function format_percentage(float $number, bool $fraction = true, int $decimals = 2) {$coefficient = $fraction ? 100 : 1;return get_string('percents', 'moodle', format_float($number * $coefficient, $decimals));}/*** Format $min and $max to localised percentages and form a string that represents a range between them.* This function does not check if $min is less than $max or not.* If both $min and $max are equal to null, this function returns an empty string.** @param float|null $min The minimum value of the range* @param float|null $max The maximum value of the range* @param bool $fraction An indicator for whether min and max are a fractions or are already multiplied by 100* @param int $decimals Sets the number of decimal points* @return string A formatted string that represents a range between $min to $max.*/protected function format_percentage_range(float $min = null, float $max = null, bool $fraction = true, int $decimals = 2) {if (is_null($min) && is_null($max)) {return '';} else {$min = $min ?: 0;$max = $max ?: 0;return $this->format_range($this->format_percentage($min, $fraction, $decimals),$this->format_percentage($max, $fraction, $decimals));}}}