TINV Function

Returns a quantile from the t distribution.

Category:	Quantile
Returned data type:	DOUBLE

Syntax

Syntax

TINV(p, df[, nc])

Arguments

p

specifies any valid expression that evaluates to a numeric probability.

Range	0 < p < 1
Data type	DOUBLE
See	<sql-expression>
See	FedSQL Expressions

df

specifies any valid expression that evaluates to a numeric degrees of freedom parameter.

Range	df > 0
Data type	DOUBLE
See	<sql-expression>
See	FedSQL Expressions

nc

specifies any valid expression that evaluates to a numeric noncentrality parameter.

Data type	DOUBLE
See	<sql-expression>
See	FedSQL Expressions

Details

The TINV function returns the p^th quantile from the Student's t distribution with degrees of freedom df and a noncentrality parameter nc. The probability that an observation from a t distribution is less than or equal to the returned quantile is p.

TINV accepts a noninteger degree of freedom parameter df. If the optional parameter nc is not specified or is 0, the quantile from the central t distribution is returned.

CAUTION:

For large values of nc, the algorithm can fail.

In that case, a missing value is returned.

Comparisons

TINV is the inverse of the PROBT function.

Example

The following statements illustrate the TINV function:

Statement	Result
select tinv(.95, 2);	2.9199855804
select tinv(.95, 2.5, 3);	11.033833625

TINV Function

Syntax

Arguments

p

df

nc

Details

Comparisons

Example

See Also