CriticalRightTail





http://www.QuantTools.com
CapeTools Query Statistical Hypothesis Objects function list

Welcome | Documentation format | QuantTools Groups | QuantTools Categories | Licence

Key TAGs | Excel Index | API Index



Given a hypothesis test object and an alpha risk value this function tests if the hypothesis is true.

A critical value is computed using the inverse cumulative distribution function.

The value of the sample statistic within the hypothesis object (mean, difference of means, variance or ratio of variance) is compared to the critical value to decide if the hypothesis can be rejected.

This function returns that critical value for the right-tail of the normal distribution.

This function requires the input of a hypothesis object key, which must have been produced via one of the following functions : HypMeanKnownSigma(), HypMeanDiffKnownSigma(), HypMean(), HypMeanDiff(), HypVariance() or HypVarianceRatio(). These functions would have returned a string 'KEY' which is to be passed to the 'HypKey' parameter of this function.



Note: Within Excel, the function is named - CT.STAT.CriticalRightTail




High level graphic of CriticalRightTail() function with parameters. Blue square node is the actual function with the parameters ordered.



Parameter Description


  1. HypKey parameter

    Key to an already created Hypothesis object.
  2. alpha parameter

    Whatever our criteria may be, if the hypothesis is true and we repeated a test of this type many times some fraction of our results would be incorrect, allowing sampling error to mislead us into believing the population mean was different than we thought. You should decide in advance how much risk we are willing to take. This number (a probability) controls that risk.


Extended information

Function Syntax

VB Syntax


Double CTQryStatHypothesisObjects.CriticalRightTail( _
String HypKey, _
Double alpha)


Excel Spreadsheet Syntax


=CT.STAT.CriticalRightTail(
Excel String Cell HypKey,
Excel Numeric Cell alpha)


C++ Syntax


static double CriticalRightTail(
std::string HypKey,
double alpha);


DotNET Syntax


System.Double CTQryStatHypothesisObjectsSA.CriticalRightTail(
System.String HypKey,
System.Double alpha);

Parameter data types

ArgNameArgTypeIsKey
HypKeyStringTRUE
alphaDoubleFALSE


Example Inputs

The first column represents the name of the parameters. The second column specifies whether the parameters are optional or not. Finally the last column provides some sample input data.
Function call input string-keys are always in the format : "NAME.EXTTAG.TICKER" The "EXTTAG.TICKER" part is determined from the output of other, capetools, object creation functions.


ArgNameIsOptional (Excel only)Example
HypKeyFALSEHypKeyNAME.EXTTAG.TICKER (from a function call)
alphaFALSE0.05


Example function usage


The C# example below contains all the sub-function calls leading up to this function call. As a result, the example can contain a lot of code.

The VB.NET, J#, C++.NET, Java, Excel VBA, Visual Basic 6 (via COM) and C++ examples below contain function code stubs for the calls leading up to this function call. However, the function call for this function is displayed.
You can easily reproduce the stub functions code from the C# example.


If you are accessing this functrion via the MiniXL libraries, this function is present within the CT.QL.Statistics20 MiniXL Excel Addin.

Within our Excel Example Addin Generator, we have used the following QuantTools sub-functions in order to prepare the arguments needed to call the CriticalRightTail() function. If you are executing this function via the MiniXL libraries, the module addin name, (in brackets, to the right of the sub-functions listed below), indicates the MiniXL library in which the sub-function is held. You will need to load this library into your Excel session (along with any other libraries that the sub-function call within the addin requires (ie - CT.QT.Utils20 addin in almost all cases) in order for the example to compute successfully.

These are the financial QuantTools sub-function calls that are used within the examples :





The objects generated by these sub-functions are inter-connected in the following way :




The following four examples demostrate calling this function within a Microsoft .NET environment

The following four examples demostrate calling this function within a non .NET environment

The following is a sample output from executing the CriticalRightTail() function call


100

Copyright (c) 2003-2007 CapeTools - All Rights Reserved.