# Documentation

## Deviations

kurtosis()  : float|string
KURT.
skew()  : float|int|string
SKEW.
sumSquares()  : float|string
DEVSQ.

### Methods

#### kurtosis()

KURT.

``` public static kurtosis(array<string|int, mixed> ...\$args) : float|string```

Returns the kurtosis of a data set. Kurtosis characterizes the relative peakedness or flatness of a distribution compared with the normal distribution. Positive kurtosis indicates a relatively peaked distribution. Negative kurtosis indicates a relatively flat distribution.

##### Parameters
\$args : array<string|int, mixed>

Data Series

float|string

#### skew()

SKEW.

``` public static skew(array<string|int, mixed> ...\$args) : float|int|string```

Returns the skewness of a distribution. Skewness characterizes the degree of asymmetry of a distribution around its mean. Positive skewness indicates a distribution with an asymmetric tail extending toward more positive values. Negative skewness indicates a distribution with an asymmetric tail extending toward more negative values.

##### Parameters
\$args : array<string|int, mixed>

Data Series

##### Return values
float|int|string

The result, or a string containing an error

#### sumSquares()

DEVSQ.

``` public static sumSquares(mixed ...\$args) : float|string```

Returns the sum of squares of deviations of data points from their sample mean.

Excel Function: DEVSQ(value1[,value2[, ...]])

\$args : mixed

Data values

float|string