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Author's title

Author*The author of this computation has been verified*
R Software Modulerwasp_hypothesisvariance4.wasp
Title produced by softwareTesting Variance - Confidence Intervals for Population Variance
Date of computationThu, 13 Nov 2008 13:07:17 -0700
Cite this page as followsStatistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?v=date/2008/Nov/13/t12266070152kdzckswcqwzmsk.htm/, Retrieved Sun, 19 May 2024 11:29:16 +0000
Statistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?pk=24817, Retrieved Sun, 19 May 2024 11:29:16 +0000
QR Codes:

Original text written by user:
IsPrivate?No (this computation is public)
User-defined keywords
Estimated Impact125

Tree of Dependent Computations

Family? (F = Feedback message, R = changed R code, M = changed R Module, P = changed Parameters, D = changed Data)
F       [Testing Variance - Confidence Intervals for Population Variance] [Q6: Porc] [2008-11-13 20:07:17] [d300b7a0882cee7d84584ad37a3d4ede] [Current]
Feedback Forum
2008-11-23 22:10:43 [Peter Van Doninck] [reply] 
De student heeft een verkeerde berekening gemaakt. Het moest met 'testing sample mean with known variance'.
Hier wordt er eveneens gebruik gemaakt van de one sided confidence interval van de right tail. Deze rechterstaart is nauwkeuriger omdat de volledige foutenmarge hier inzit. Er wordt naar de rechterkant gekeken omdat een teveel aan vet hierbij belangrijk is. Ook hier is de waarde 15,46% kleiner dan 18,92%, waardoor het dus binnen het 95% betrouwbaarheidsinterval ligt.
2008-11-24 14:21:04 [Julian De Ruyter] [reply] 
Er werd een verkeerde berekening gemaakt, dit is de correcte: http://www.freestatistics.org/blog/index.php?v=date/2008/Nov/24/t12275363831lkyb3q9rxr4i62.htm
we concluderen dan dat als we uit gaan van een 0-hypothese van 15,2% in plaats van een 0-hypothese van 15%, dan ligt het gemiddelde van de steekproef (0,1546) nog altijd lager dan 0.186676559191704. Dit ligt dan nog altijd binnen het 95%-betrouwbaarheidsinterval.
2008-11-24 16:10:10 [Sofie Sergoynne] [reply] 
Ik heb de foute berekening gemaakt. Het moest met 'testing sample mean with known variance'. Er wordt eveneens gebruikt gemaakt van de one-sided confidence interval in de right tail. De 5% foutmarge ligt hierbij volledig in het interval. De waarde 15,46% kleiner dan 18,92%, waardoor het dus binnen het 95% betrouwbaarheidsinterval ligt.

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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'Gwilym Jenkins' @ 72.249.127.135

\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 & 'Gwilym Jenkins' @ 72.249.127.135 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=24817&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]'Gwilym Jenkins' @ 72.249.127.135[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=24817&T=0

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=24817&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'Gwilym Jenkins' @ 72.249.127.135






Testing Variance - Confidence Intervals for Population Variance
Sample size27
Sample variance0.152
Confidence interval0.95
Type of IntervalLeft tailRight tail
Two-sided confidence interval at 0.950.09426768040004940.285468587449586
Left one-sided confidence interval at 0.950.101632658033507+inf
Right one-sided confidence interval at 0.9500.256971179050303
more information about confidence interval

\begin{tabular}{lllllllll}
\hline
Testing Variance - Confidence Intervals for Population Variance \tabularnewline
Sample size & 27 \tabularnewline
Sample variance & 0.152 \tabularnewline
Confidence interval & 0.95 \tabularnewline
Type of Interval & Left tail & Right tail \tabularnewline
Two-sided confidence interval at  0.95 & 0.0942676804000494 & 0.285468587449586 \tabularnewline
Left one-sided confidence interval at  0.95 & 0.101632658033507 & +inf \tabularnewline
Right one-sided confidence interval at  0.95 & 0 & 0.256971179050303 \tabularnewline
more information about confidence interval \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=24817&T=1

[TABLE]
[ROW][C]Testing Variance - Confidence Intervals for Population Variance[/C][/ROW]
[ROW][C]Sample size[/C][C]27[/C][/ROW]
[ROW][C]Sample variance[/C][C]0.152[/C][/ROW]
[ROW][C]Confidence interval[/C][C]0.95[/C][/ROW]
[ROW][C]Type of Interval[/C][C]Left tail[/C][C]Right tail[/C][/ROW]
[ROW][C]Two-sided confidence interval at  0.95[/C][C]0.0942676804000494[/C][C]0.285468587449586[/C][/ROW]
[ROW][C]Left one-sided confidence interval at  0.95[/C][C]0.101632658033507[/C][C]+inf[/C][/ROW]
[ROW][C]Right one-sided confidence interval at  0.95[/C][C]0[/C][C]0.256971179050303[/C][/ROW]
[ROW][C]more information about confidence interval[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=24817&T=1

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=24817&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 Population Variance
Sample size27
Sample variance0.152
Confidence interval0.95
Type of IntervalLeft tailRight tail
Two-sided confidence interval at 0.950.09426768040004940.285468587449586
Left one-sided confidence interval at 0.950.101632658033507+inf
Right one-sided confidence interval at 0.9500.256971179050303
more information about confidence interval


Figures (Output of Computation)

Input Parameters & R Code

Parameters (Session):
par1 = 27 ; par2 = 0.012 ; par3 = 0.1546 ; par4 = 0.15 ; par5 = 0.05 ; par6 = 0.152 ;
Parameters (R input):
par1 = 27 ; par2 = 0.152 ; par3 = 0.95 ;
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
ub <- par2 * df / qchisq(halfalpha,df)
ua <- par2 * df / qchisq(1-halfalpha,df)
ua
ub
ur <- par2 * df / qchisq(1-par3,df)
ur
ul <- par2 * df / qchisq(par3,df)
ul
load(file='createtable')
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,hyperlink('ht_variance.htm','Testing Variance - Confidence Intervals for Population 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,'Sample variance',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#ex4', 'more information about confidence interval','example'),3,TRUE)
a<-table.row.end(a)
a<-table.end(a)
table.save(a,file='mytable.tab')