ILIAS\Test\Statistics\Statistics Class Reference

Collaboration diagram for ILIAS\Test\Statistics\Statistics:

Public Member Functions
	__construct (\ilTestEvaluationData $eval_data)
	getEvaluationDataOfMedianUser ()
	min ()
	max ()
	Calculates the maximum value. More...
	count ()
	Calculates number of data values. More...
	sum_n (int $n)
	Calculates the sum of x_1^n + x_2^n + ... More...
	sum ()
	Calculates the sum of x_1 + x_2 + ... More...
	sum2 ()
	Calculates the sum of x_1^2 + x_2^2 + ... More...
	product_n (int $n)
	Calculates the product of x_1^n * x_2^n * ... More...
	product (int $n)
	Calculates the product of x_1 * x_2 * ... More...
	arithmeticMean ()
	Arithmetic mean of the data values xbar = (1/n)*∑x_i. More...
	geometricMean ()
	Geometric mean of the data values geometric_mean = (x_1 * x_2 * ... More...
	harmonicMean ()
	Harmonic mean of the data values harmonic_mean = n/(1/x_1 + 1/x_2 + ... More...
	median ()
	Median of the data values. More...
	rank (float $value)
	Returns the rank of a given value. More...
	rankMedian ()
	Returns the rank of the median. More...
	quantile (float $n)
	n-Quantile of the data values More...

Private Attributes
array	$stat_data = []
ilTestEvaluationUserData	$median_user = null

Detailed Description

Definition at line 23 of file Statistics.php.

Constructor & Destructor Documentation

__construct()

ILIAS\Test\Statistics\Statistics::__construct

(

\ilTestEvaluationData

$eval_data

)

Definition at line 28 of file Statistics.php.

References ilTestEvaluationData\getParticipant(), ilTestEvaluationData\getParticipants(), ilTestEvaluationUserData\getReached(), ILIAS\Test\Statistics\Statistics\median(), and ILIAS\UI\examples\Symbol\Glyph\Sort\sort().

    {
        $median_array = array_map(
            fn(\ilTestEvaluationUserData $v): float => $v->getReached(),
            $eval_data->getParticipants()
        );

        $this->stat_data = array_values($median_array);
        sort($this->stat_data);

        if (($median_user_id = array_search($this->median(), $median_array)) !== false) {
            $this->median_user = $eval_data->getParticipant($median_user_id);
        }
    }

Here is the call graph for this function:

Member Function Documentation

arithmeticMean()

ILIAS\Test\Statistics\Statistics::arithmeticMean

(

)

Arithmetic mean of the data values xbar = (1/n)*∑x_i.

Definition at line 142 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\count(), null, and ILIAS\Test\Statistics\Statistics\sum().

                                    : ?float
    {
        $sum = $this->sum();
        if ($sum === null) {
            return null;
        }

        $count = $this->count();
        if ($count === 0) {
            return null;
        }
        return (float) ($sum / $count);
    }

Here is the call graph for this function:

count()

ILIAS\Test\Statistics\Statistics::count

(

)

Calculates number of data values.

Definition at line 72 of file Statistics.php.

Referenced by ILIAS\Test\Statistics\Statistics\arithmeticMean(), ILIAS\Test\Statistics\Statistics\geometricMean(), ILIAS\Test\Statistics\Statistics\harmonicMean(), ILIAS\Test\Statistics\Statistics\median(), ILIAS\Test\Statistics\Statistics\quantile(), ILIAS\Test\Statistics\Statistics\rank(), and ILIAS\Test\Statistics\Statistics\rankMedian().

                           : int
    {
        return count($this->stat_data);
    }

Here is the caller graph for this function:

geometricMean()

ILIAS\Test\Statistics\Statistics::geometricMean

(

)

Geometric mean of the data values geometric_mean = (x_1 * x_2 * ...

• x_n)^(1/n)

The geometric mean of a set of positive data is defined as the product of all the members of the set, raised to a power equal to the reciprocal of the number of members.

Definition at line 164 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\count(), null, and ILIAS\Test\Statistics\Statistics\product().

                                   : ?float
    {
        $prod = $this->product(1);
        if (($prod === null) || ($prod === 0)) {
            return null;
        }
        $count = $this->count();
        if ($count === 0) {
            return null;
        }
        return pow((float) $prod, (float) (1 / $count));
    }

Here is the call graph for this function:

getEvaluationDataOfMedianUser()

ILIAS\Test\Statistics\Statistics::getEvaluationDataOfMedianUser

(

)

Definition at line 43 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\$median_user.

                                                   : ?\ilTestEvaluationUserData
    {
        return $this->median_user;
    }

harmonicMean()

ILIAS\Test\Statistics\Statistics::harmonicMean

(

)

Harmonic mean of the data values harmonic_mean = n/(1/x_1 + 1/x_2 + ...

• 1/x_n)

Definition at line 181 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\count(), ILIAS\Test\Statistics\Statistics\min(), and null.

                                  : ?float
    {
        $min = $this->min();
        if (($min === null) or ($min === 0)) {
            return null;
        }
        $count = $this->count();
        if ($count === 0) {
            return null;
        }
        $sum = 0.0;
        foreach ($this->stat_data as $value) {
            $sum += 1 / $value;
        }
        return $count / $sum;
    }

Here is the call graph for this function:

max()

ILIAS\Test\Statistics\Statistics::max

(

)

Calculates the maximum value.

Definition at line 60 of file Statistics.php.

References null.

                         : ?float
    {
        if ($this->stat_data === []) {
            return null;
        }

        return max($this->stat_data);
    }

median()

ILIAS\Test\Statistics\Statistics::median

(

)

Median of the data values.

Definition at line 201 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\count(), and null.

Referenced by ILIAS\Test\Statistics\Statistics\__construct().

                            : ?float
    {
        if ($this->stat_data === []) {
            return null;
        }

        $count = $this->count();
        if ((count($this->stat_data) % 2) === 0) {
            return ($this->stat_data[($count / 2) - 1] + $this->stat_data[($count / 2)]) / 2;
        }

        return $this->stat_data[(($count + 1) / 2) - 1];
    }

Here is the call graph for this function:

Here is the caller graph for this function:

min()

ILIAS\Test\Statistics\Statistics::min

(

)

Definition at line 48 of file Statistics.php.

References null.

Referenced by ILIAS\Test\Statistics\Statistics\harmonicMean(), and ILIAS\Test\Statistics\Statistics\product_n().

                         : ?float
    {
        if ($this->stat_data === []) {
            return null;
        }

        return min($this->stat_data);
    }

Here is the caller graph for this function:

product()

ILIAS\Test\Statistics\Statistics::product

(

int

$n

)

Calculates the product of x_1 * x_2 * ...

• x_i

Definition at line 133 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\product_n().

Referenced by ILIAS\Test\Statistics\Statistics\geometricMean().

                                   : ?float
    {
        return $this->product_n(1);
    }

Here is the call graph for this function:

Here is the caller graph for this function:

product_n()

ILIAS\Test\Statistics\Statistics::product_n

(

int

$n

)

Calculates the product of x_1^n * x_2^n * ...

• x_i^n

Definition at line 113 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\min(), and null.

Referenced by ILIAS\Test\Statistics\Statistics\product().

                                     : ?float
    {
        if ($this->stat_data === []) {
            return null;
        }

        if ($this->min() === 0) {
            return 0.0;
        }

        $prod_n = 1.0;
        foreach ($this->stat_data as $value) {
            $prod_n *= pow((float) $value, (float) $n);
        }
        return $prod_n;
    }

Here is the call graph for this function:

Here is the caller graph for this function:

quantile()

ILIAS\Test\Statistics\Statistics::quantile

(

float

$n

)

n-Quantile of the data values

Definition at line 252 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\count(), ILIAS\Repository\int(), and null.

                                      : ?float
    {
        $count = $this->count();
        if ($count === 0) {
            return null;
        }

        $nprod = ($n / 100) * $count;
        if (intval($nprod) != $nprod) {
            return $this->stat_data[ceil($nprod) - 1];
        }

        if ($nprod === 0.0) {
            return $this->stat_data[0];
        }

        if ($nprod === (float) $count) {
            return $this->stat_data[(int) $nprod - 1];
        }

        return ($this->stat_data[(int) $nprod - 1] + $this->stat_data[(int) $nprod]) / 2;
    }

Here is the call graph for this function:

rank()

ILIAS\Test\Statistics\Statistics::rank

(

float

$value

)

Returns the rank of a given value.

Definition at line 218 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\count(), and null.

                                      : ?int
    {
        $rank = array_search($value, $this->stat_data);
        if ($rank === false) {
            return null;
        }

        return $this->count() - $rank;
    }

Here is the call graph for this function:

rankMedian()

ILIAS\Test\Statistics\Statistics::rankMedian

(

)

Returns the rank of the median.

This method is different from the rank method because the median could be the arithmetic mean of the two middle values when the data size is even. In this case the median could a value which is not part of the data set.

Definition at line 235 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\count(), and null.

                                : ?int
    {
        $count = $this->count();
        if ($count === 0) {
            return null;
        }

        if (($count % 2) === 0) {
            return $count / 2;
        }

        return ($count + 1) / 2;
    }

Here is the call graph for this function:

sum()

ILIAS\Test\Statistics\Statistics::sum

(

)

Calculates the sum of x_1 + x_2 + ...

• x_i

Definition at line 96 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\sum_n().

Referenced by ILIAS\Test\Statistics\Statistics\arithmeticMean().

                         : ?float
    {
        return $this->sum_n(1);
    }

Here is the call graph for this function:

Here is the caller graph for this function:

sum2()

ILIAS\Test\Statistics\Statistics::sum2

(

)

Calculates the sum of x_1^2 + x_2^2 + ...

• x_i^2

Definition at line 105 of file Statistics.php.

References ILIAS\Test\Statistics\Statistics\sum_n().

                          : float
    {
        return $this->sum_n(2);
    }

Here is the call graph for this function:

sum_n()

ILIAS\Test\Statistics\Statistics::sum_n

(

int

$n

)

Calculates the sum of x_1^n + x_2^n + ...

• x_i^n

Definition at line 80 of file Statistics.php.

References null.

Referenced by ILIAS\Test\Statistics\Statistics\sum(), and ILIAS\Test\Statistics\Statistics\sum2().

                                 : ?float
    {
        if ($this->stat_data === []) {
            return null;
        }

        $sum_n = 0;
        foreach ($this->stat_data as $value) {
            $sum_n += pow((float) $value, (float) $n);
        }
        return $sum_n;
    }

Here is the caller graph for this function:

Field Documentation

$median_user

ilTestEvaluationUserData ILIAS\Test\Statistics\Statistics::$median_user = null

private

Definition at line 26 of file Statistics.php.

Referenced by ILIAS\Test\Statistics\Statistics\getEvaluationDataOfMedianUser().

$stat_data

array ILIAS\Test\Statistics\Statistics::$stat_data = []

private

Definition at line 25 of file Statistics.php.

---

The documentation for this class was generated from the following file:

• components/ILIAS/Test/src/Statistics/Statistics.php