WorksheetFunction.NegBinom_Dist Method

Returns the negative binomial distribution. NegBinom_Dist returns the probability that there will be number_f failures before the number_s-th success, when the constant probability of a success is probability_s. This function is similar to the binomial distribution, except that the number of successes is fixed, and the number of trials is variable. Like the binomial, trials are assumed to be independent.

Namespace:  Microsoft.Office.Interop.Excel
Assembly:  Microsoft.Office.Interop.Excel (in Microsoft.Office.Interop.Excel.dll)

Syntax

'Declaration
Function NegBinom_Dist ( _
    Arg1 As Double, _
    Arg2 As Double, _
    Arg3 As Double, _
    Arg4 As Boolean _
) As Double
'Usage
Dim instance As WorksheetFunction
Dim Arg1 As Double
Dim Arg2 As Double
Dim Arg3 As Double
Dim Arg4 As Boolean
Dim returnValue As Double

returnValue = instance.NegBinom_Dist(Arg1, _
    Arg2, Arg3, Arg4)

double NegBinom_Dist(
    double Arg1,
    double Arg2,
    double Arg3,
    bool Arg4
)

Parameters

• Arg1
  Type: System.Double

  Number_f - the number of failures.

• Arg2
  Type: System.Double

  Number_s - the threshold number of successes.

• Arg3
  Type: System.Double

  Probability_s - the probability of a success.

• Arg4
  Type: System.Boolean

  Cumulative - A logical value that determines the form of the function. If cumulative is true, NegBinom_Dist returns the cumulative distribution function; if false, it returns the probability density function.

Return Value

Type: System.Double

Remarks

For example, you need to find 10 people with excellent reflexes, and you know the probability that a candidate has these qualifications is 0.3. NegBinom_Dist calculates the probability that you will interview a certain number of unqualified candidates before finding all 10 qualified candidates:

Number_f and number_s are truncated to integers.

If any argument is nonnumeric, NegBinom_Dist returns the #VALUE! error value.

If probability_s < 0 or if probability > 1, NegBinom_Dist returns the #NUM! error value.

If number_f < 0 or number_s < 1, NegBinom_Dist returns the #NUM! error value.

The equation for the negative binomial distribution is:

Figure 1: Equation for the negative binomial distribution

where:

x is number_f, r is number_s, and p is probability_s.

See Also

Reference

WorksheetFunction Interface

WorksheetFunction Members

Microsoft.Office.Interop.Excel Namespace