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Description of Statistical Computation

Author's title

Author*Unverified author*
R Software Modulerwasp_hypothesismean6.wasp
Title produced by softwareTesting Sample Mean with known Variance - Confidence Interval
Date of computationThu, 13 Nov 2008 15:51:37 -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/t1226616718gqlz7r35pqhykgd.htm/, Retrieved Mon, 27 May 2024 07:16:36 +0000
Statistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?pk=24879, Retrieved Mon, 27 May 2024 07:16:36 +0000
QR Codes:

Original text written by user:
IsPrivate?No (this computation is public)
User-defined keywords
Estimated Impact139

Tree of Dependent Computations

Family? (F = Feedback message, R = changed R code, M = changed R Module, P = changed Parameters, D = changed Data)
F       [Testing Sample Mean with known Variance - Confidence Interval] [] [2008-11-13 22:51:37] [00d8a67dacc57b43a0eea87363e750e0] [Current]
Feedback Forum
2008-11-19 11:45:00 [Glenn Maras] [reply] 
De juiste berekeningen zijn uitgevoerd maar de conclusie is niet correct.
We gebruiken hier opnieuw de Right one-sided confidence interval at 0.95, en we zien dat bij de nieuwe H0 de grenswaarde gelijk is aan 0.1866
De sample mean van 0.1546 ligt dus opnieuw lager en dus binnen het btrouwbaarheidsinterval van 95%
2008-11-23 17:58:33 [c97d2ae59c98cf77a04815c1edffab5a] [reply] 
de student heeft wel de juiste conclusie gevormd en de gegevens correct ingevoerd, maar niet de nodige uitleg gegeven. volgens mij kan je kiezen of je 1-of 2-sided interval neemt, je moet er alleen de juiste verklaring voor geven.
2-sided: Ook al veranderen we de nulhypothese van 15% in 15,2%, dan nog ligt het steekproefgemiddelde van 15,46% tussen een vetpercentage van 11.06% en 19.33% en dus binnen het 2-zijdig betrouwbaarheidsinterval van 95%. Dit geldt wanneer we besluiten dat het vetpercentage niet te veel of te weinig mag zijn. Het vetpercentage mag niet onder de grens van 11,06% gaan en de 19,33% niet overschrijden. Zo wel? => fraude
1-sided: In het geval van het vermoeden van fraude, is er enkel een afwijking naar boven en maken we gebruik van het ‘Right one-sided confidence interval at 0.95’. hierbij kunnen we afleiden dat 15,46% nog altijd binnen het betrouwbaarheidsinterval [–inf, 18,67%]. En de nulhypothese dus niet verworpen moet worden. Hierbij mag het vetpercentage de 18,67% niet overschrijden. zo wel?=> fraude
2008-11-23 20:06:24 [Peter Van Doninck] [reply] 
De student heeft de juiste berekeningen gemaakt, enkel de conclusie is niet correct. Hier wordt er ook gekeken naar de right one sided confidence interval at 0,95. De rechter staart is nauwkeuriger omdat de volledige 5% foutenmarge een deze kant wordt toegewezen. Hier gebruiken we echter de waarde 15,2% ipv 15%. 0,1546 ligt echter lager dan 0,189, waardoor het binnen het 95% betrouwbaarheidsinterval ligt.
2008-11-24 19:29:28 [Annemiek Hoofman] [reply] 
Omdat ik tijdens de hele opdracht al voor een one-tailed heb gekozen, zou ik nu consistent blijven en kiezen voor Right one-sided confidence interval at 0.95. De bevindingen staan hierboven zeer goed uitgelegd.

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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 time2 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 & 2 seconds \tabularnewline
R Server & 'Gwilym Jenkins' @ 72.249.127.135 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=24879&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]2 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=24879&T=0

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=24879&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 time2 seconds
R Server'Gwilym Jenkins' @ 72.249.127.135






Testing Sample Mean with known Variance
Population variance0.012
Sample size27
Null hypothesis (H0)0.152
Confidence interval0.95
Type of IntervalLeft tailRight tail
Two-sided confidence interval at 0.950.1106803311796960.193319668820304
Left one-sided confidence interval at 0.950.117323440808296+inf
Right one-sided confidence interval at 0.95-inf0.186676559191704
more information about confidence interval

\begin{tabular}{lllllllll}
\hline
Testing Sample Mean with known Variance \tabularnewline
Population variance & 0.012 \tabularnewline
Sample size & 27 \tabularnewline
Null hypothesis (H0) & 0.152 \tabularnewline
Confidence interval & 0.95 \tabularnewline
Type of Interval & Left tail & Right tail \tabularnewline
Two-sided confidence interval at  0.95 & 0.110680331179696 & 0.193319668820304 \tabularnewline
Left one-sided confidence interval at  0.95 & 0.117323440808296 & +inf \tabularnewline
Right one-sided confidence interval at  0.95 & -inf & 0.186676559191704 \tabularnewline
more information about confidence interval \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=24879&T=1

[TABLE]
[ROW][C]Testing Sample Mean with known Variance[/C][/ROW]
[ROW][C]Population variance[/C][C]0.012[/C][/ROW]
[ROW][C]Sample size[/C][C]27[/C][/ROW]
[ROW][C]Null hypothesis (H0)[/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]0.110680331179696[/C][C]0.193319668820304[/C][/ROW]
[ROW][C]Left one-sided confidence interval at  0.95[/C][C]0.117323440808296[/C][C]+inf[/C][/ROW]
[ROW][C]Right one-sided confidence interval at  0.95[/C][C]-inf[/C][C]0.186676559191704[/C][/ROW]
[ROW][C]more information about confidence interval[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=24879&T=1

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=24879&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 Sample Mean with known Variance
Population variance0.012
Sample size27
Null hypothesis (H0)0.152
Confidence interval0.95
Type of IntervalLeft tailRight tail
Two-sided confidence interval at 0.950.1106803311796960.193319668820304
Left one-sided confidence interval at 0.950.117323440808296+inf
Right one-sided confidence interval at 0.95-inf0.186676559191704
more information about confidence interval


Figures (Output of Computation)

Input Parameters & R Code

Parameters (Session):
par1 = 0.012 ; par2 = 27 ; par3 = 0.152 ; par4 = 0.95 ;
Parameters (R input):
par1 = 0.012 ; par2 = 27 ; par3 = 0.152 ; par4 = 0.95 ;
R code (references can be found in the software module):
par1<-as.numeric(par1)
par2<-as.numeric(par2)
par3<-as.numeric(par3)
par4<-as.numeric(par4)
sigma <- sqrt(par1)
sqrtn <- sqrt(par2)
ua <- par3 - abs(qnorm((1-par4)/2))* sigma / sqrtn
ub <- par3 + abs(qnorm((1-par4)/2))* sigma / sqrtn
ua
ub
ul <- par3 - qnorm(par4) * sigma / sqrtn
ul
ur <- par3 + qnorm(par4) * sigma / sqrtn
ur
load(file='createtable')
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,hyperlink('ht_mean_knownvar.htm','Testing Sample Mean with known Variance','learn more about Statistical Hypothesis Testing about the Mean when the Variance is known'),3,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Population variance',header=TRUE)
a<-table.element(a,par1,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Sample size',header=TRUE)
a<-table.element(a,par2,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Null hypothesis (H0)',header=TRUE)
a<-table.element(a,par3,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Confidence interval',header=TRUE)
a<-table.element(a,par4,2)
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 ',par4), 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 ',par4), 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 ',par4), header=TRUE)
a<-table.element(a,'-inf')
a<-table.element(a,ur)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a, hyperlink('ht_mean_knownvar.htm#ex6', 'more information about confidence interval','example'),3,TRUE)
a<-table.row.end(a)
a<-table.end(a)
table.save(a,file='mytable.tab')