Finding and removing outliers in PHP

Question

Suppose I sample a selection of database records that return the following numbers:

20.50, 80.30, 70.95, 15.25, 99.97, 85.56, 69.77

Is ther

Answer 1

For a normally distributed set of data, removes values more than 3 standard deviations from the mean.

 $outlier) {
            $ret[] = $a;
        }
    }
    return $ret;
}