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Description of Statistical Computation

Author's title

Author*The author of this computation has been verified*
R Software Modulerwasp_hypothesisvariance3.wasp
Title produced by softwareTesting Variance - Confidence Intervals for Sample Variance
Date of computationTue, 26 Oct 2010 18:36:03 +0000
Cite this page as followsStatistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?v=date/2010/Oct/26/t1288118070gihibn9sepwrxy2.htm/, Retrieved Sun, 28 Apr 2024 04:09:12 +0000
Statistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?pk=89538, Retrieved Sun, 28 Apr 2024 04:09:12 +0000
QR Codes:

Original text written by user:
IsPrivate?No (this computation is public)
User-defined keywords
Estimated Impact133

Tree of Dependent Computations

Family? (F = Feedback message, R = changed R code, M = changed R Module, P = changed Parameters, D = changed Data)
-     [Factor Analysis] [Sleep in Mammals ...] [2010-03-21 11:39:53] [b98453cac15ba1066b407e146608df68]
- RMPD  [Testing Mean with unknown Variance - Critical Value] [Hypothesis Test a...] [2010-10-19 11:45:26] [b98453cac15ba1066b407e146608df68]
-   PD    [Testing Mean with unknown Variance - Critical Value] [Intrinsic motivat...] [2010-10-22 14:27:55] [6bc4f9343b7ea3ef5a59412d1f72bb2b]
- RMPD      [Population Mean Test] [Smallest possible...] [2010-10-22 14:53:43] [6bc4f9343b7ea3ef5a59412d1f72bb2b]
- RMPD        [Testing Variance - Confidence Intervals for Sample Variance] [Variance = 13 Men] [2010-10-23 09:26:09] [6bc4f9343b7ea3ef5a59412d1f72bb2b]
F               [Testing Variance - Confidence Intervals for Sample Variance] [Variantie 13 mannen] [2010-10-26 18:28:53] [8ef75e99f9f5061c72c54640f2f1c3e7]
F   P               [Testing Variance - Confidence Intervals for Sample Variance] [Variantie 13 vrouwen] [2010-10-26 18:36:03] [e26438ba7029caa0090c95690001dbf5] [Current]
Feedback Forum
2010-10-29 11:06:09 [00c625c7d009d84797af914265b614f9] [reply] 
Voor vrouwen kunnen we eerst de eenzijdige test berekenen in de software via 'Testing Variance - Critical Value' ->
Critical value: 13.7753607125852
Conclusion: Reject the null hypothesis.
Dus de vrouwelijk L1 variantie is significant groter dan 13.
Voor de tweezijdige test gebruiken we in de software software 'Testing Variance - Confidence Intervals for Population Variance'.

We komen dit interval uit [12.0111466061063,16.8327022129086]-> 13 ligt binnen dit interval.

We kunnen dus concluderen dat waarde van de variantie voor L1 bij vrouwen significant groter is dan 13 maar ook niet significant verschilt van 13.
2010-11-02 14:50:25 [1951de723fd2749e12bc2f1a75bd3e74] [reply] 
Voor vrouwen krijgen we wel een variantie die verschillend is van 13, namelijk 13,77 (kritieke waarde). Aangezien 13,77 > 13, verwerpen we nul hypothese. We besluiten dat de variantie voor vrouwen verschilt van 13 indien we een type 1 fout gebruiken van 35.
Uit deze berekening kunnen we niet besluiten dat de variantie van vrouwen groter is dan die van mannen. Het is een eenzijdige test en we hebben 2 spreidingen nodig om dat de testen. Deze toetsen zijn altijd deterministisch, de 13 waartegen we toetsen ligt vast, maar we kunnen geen verschil besluiten tussen de 2. We kunnen (tweezijdig) het 65% betrouwbaarheidsinterval berekenen voor de sample variance. Dan zien we dat bij vrouwen de variantie groter is dan 13.

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Dataset

Tables (Output of Computation)





Summary of computational transaction
Raw Inputview raw input (R code)
Raw Outputview raw output of R engine
Computing time1 seconds
R Server'Sir Ronald Aylmer Fisher' @ 193.190.124.24

\begin{tabular}{lllllllll}
\hline
Summary of computational transaction \tabularnewline
Raw Input & view raw input (R code)  \tabularnewline
Raw Output & view raw output of R engine  \tabularnewline
Computing time & 1 seconds \tabularnewline
R Server & 'Sir Ronald Aylmer Fisher' @ 193.190.124.24 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=89538&T=0

[TABLE]
[ROW][C]Summary of computational transaction[/C][/ROW]
[ROW][C]Raw Input[/C][C]view raw input (R code) [/C][/ROW]
[ROW][C]Raw Output[/C][C]view raw output of R engine [/C][/ROW]
[ROW][C]Computing time[/C][C]1 seconds[/C][/ROW]
[ROW][C]R Server[/C][C]'Sir Ronald Aylmer Fisher' @ 193.190.124.24[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=89538&T=0

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=89538&T=0

As an alternative you can also use a QR Code:  
QR Code


The GUIDs for individual cells are displayed in the table below:

Summary of computational transaction
Raw Inputview raw input (R code)
Raw Outputview raw output of R engine
Computing time1 seconds
R Server'Sir Ronald Aylmer Fisher' @ 193.190.124.24






Testing Variance - Confidence Intervals for Sample Variance
Sample size63
Null hypothesis (H0)13
Confidence interval0.65
Type of IntervalLeft tailRight tail
Two-sided confidence interval at 0.6510.812286565637015.1525916690979
Left one-sided confidence interval at 0.6511.9870808512614+inf
Right one-sided confidence interval at 0.65013.7753607125852
more information about confidence interval

\begin{tabular}{lllllllll}
\hline
Testing Variance - Confidence Intervals for Sample Variance \tabularnewline
Sample size & 63 \tabularnewline
Null hypothesis (H0) & 13 \tabularnewline
Confidence interval & 0.65 \tabularnewline
Type of Interval & Left tail & Right tail \tabularnewline
Two-sided confidence interval at  0.65 & 10.8122865656370 & 15.1525916690979 \tabularnewline
Left one-sided confidence interval at  0.65 & 11.9870808512614 & +inf \tabularnewline
Right one-sided confidence interval at  0.65 & 0 & 13.7753607125852 \tabularnewline
more information about confidence interval \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=89538&T=1

[TABLE]
[ROW][C]Testing Variance - Confidence Intervals for Sample Variance[/C][/ROW]
[ROW][C]Sample size[/C][C]63[/C][/ROW]
[ROW][C]Null hypothesis (H0)[/C][C]13[/C][/ROW]
[ROW][C]Confidence interval[/C][C]0.65[/C][/ROW]
[ROW][C]Type of Interval[/C][C]Left tail[/C][C]Right tail[/C][/ROW]
[ROW][C]Two-sided confidence interval at  0.65[/C][C]10.8122865656370[/C][C]15.1525916690979[/C][/ROW]
[ROW][C]Left one-sided confidence interval at  0.65[/C][C]11.9870808512614[/C][C]+inf[/C][/ROW]
[ROW][C]Right one-sided confidence interval at  0.65[/C][C]0[/C][C]13.7753607125852[/C][/ROW]
[ROW][C]more information about confidence interval[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=89538&T=1

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=89538&T=1

As an alternative you can also use a QR Code:  
QR Code


The GUIDs for individual cells are displayed in the table below:

Testing Variance - Confidence Intervals for Sample Variance
Sample size63
Null hypothesis (H0)13
Confidence interval0.65
Type of IntervalLeft tailRight tail
Two-sided confidence interval at 0.6510.812286565637015.1525916690979
Left one-sided confidence interval at 0.6511.9870808512614+inf
Right one-sided confidence interval at 0.65013.7753607125852
more information about confidence interval


Figures (Output of Computation)

Input Parameters & R Code

Parameters (Session):
par1 = 63 ; par2 = 13 ; par3 = 0.65 ;
Parameters (R input):
par1 = 63 ; par2 = 13 ; par3 = 0.65 ;
R code (references can be found in the software module):
par1<-as.numeric(par1)
par2<-as.numeric(par2)
par3<-as.numeric(par3)
df <- par1 - 1
halfalpha <- (1 - par3) / 2
ua <- qchisq(halfalpha,df) * par2 / df
ub <- qchisq(1-halfalpha,df) * par2 / df
ua
ub
ul <- qchisq(1-par3,df) * par2 / df
ul
ur <- qchisq(par3,df) * par2 / df
ur
load(file='createtable')
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,hyperlink('ht_variance.htm','Testing Variance - Confidence Intervals for Sample Variance','learn more about Statistical Hypothesis Testing about the Variance'),3,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Sample size',header=TRUE)
a<-table.element(a,par1,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Null hypothesis (H0)',header=TRUE)
a<-table.element(a,par2,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Confidence interval',header=TRUE)
a<-table.element(a,par3,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Type of Interval',header=TRUE)
a<-table.element(a,'Left tail',header=TRUE)
a<-table.element(a,'Right tail',header=TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,paste('Two-sided confidence interval at ',par3), header=TRUE)
a<-table.element(a,ua)
a<-table.element(a,ub)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,paste('Left one-sided confidence interval at ',par3), header=TRUE)
a<-table.element(a,ul)
a<-table.element(a,'+inf')
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,paste('Right one-sided confidence interval at ',par3), header=TRUE)
a<-table.element(a,'0')
a<-table.element(a,ur)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a, hyperlink('ht_variance.htm#ex3', 'more information about confidence interval','example'),3,TRUE)
a<-table.row.end(a)
a<-table.end(a)
table.save(a,file='mytable.tab')