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Description of Statistical Computation

Author's title

Author*The author of this computation has been verified*
R Software Modulerwasp_hypothesismean2.wasp
Title produced by softwareTesting Mean with known Variance - p-value
Date of computationMon, 10 Nov 2008 04:43:21 -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/10/t1226317447wm2rkrg1z0s1k2v.htm/, Retrieved Sun, 19 May 2024 10:45:40 +0000
Statistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?pk=22959, Retrieved Sun, 19 May 2024 10:45:40 +0000
QR Codes:

Original text written by user:
IsPrivate?No (this computation is public)
User-defined keywordsQ2
Estimated Impact189

Tree of Dependent Computations

Family? (F = Feedback message, R = changed R code, M = changed R Module, P = changed Parameters, D = changed Data)
F       [Testing Mean with known Variance - p-value] [Q2] [2008-11-10 11:43:21] [783db4b4a0f63b73ca8b14666b7f4329] [Current]
F         [Testing Mean with known Variance - p-value] [q2] [2008-11-11 15:11:56] [988ab43f527fc78aae41c84649095267]
Feedback Forum
2008-11-14 14:04:20 [Dana Molenberghs] [reply] 
De p-value (41%) is veel groter dan de alfa-fout (5%). De nulhypothese mag niet verworpen worden. Het verschil, tussen 15% en 15,46%, is dus aan toeval te wijten. Er is dus niet opzettelijk slecht vlees geleverd. Ik zou dus geen advocaat inhuren omdat de kans op vergissing te groot is.
2008-11-18 08:33:26 [Ellen Smolders] [reply] 
De student heeft de vraag correct beantwoord maar er kunnen nog enkele dingen worden bijgevoegd. Wanneer we de opdracht zorgvuldig lezen kunnen we uit ‘a strong suspicion’ afleiden dat we een sterk VERMOEDEN hebben dat het varkensvlees te veel vet bevat, dit vermoeden wordt geuit. Doordat we vermoeden dat er TE VEEL vet (dit gaat dus naar één richting) in het varkensvlees zit, sluiten we de optie naar de andere richting uit, en gebruiken we dus een eenzijdige test.
We kunnen opmerken dat er een hoge p waarde wordt gegeven, nl. 0.41363.., dit betekent dat de kans dat de klacht ongegrond is, groot is, nl. 41%. Dit betekent dat je grote risico’s pakt, maar deze beslissing neemt het management zelf. Je kan de risico’s vermijden door dit te spreiden over veel beleggingen, daardoor zal je globaal gezien wel winst maken. We kunnen besluiten dat we geen klacht zullen indien want de kans dat we ons vergissen bij het verwerpen van de nullhypothese is veel te groot.
2008-11-20 15:49:17 [Julie Leurentop] [reply] 
Ik sluit me aan bij het antwoord van de vorige 2 studenten. De kans dat we ons vergissen is 41%. Dit is te groot om ons effectief te vergissen.
2008-11-24 11:04:59 [Lindsay Heyndrickx] [reply] 
Dit is een correct antwoord.
Hier moet je de p waarde gebruiken. Dit is eenzijdig want je hebt het vermoeden dat het in 1 richting gaat. De p waarde is groter dan de alfa waarde dus hier is dit niet significant. Je moet hier dus geen kosten doen om een advocaat te nemen. Kans om de nul hypothese te verwerpen is 41%. We doen hier dus geen aangifte.

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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 time4 seconds
R Server'George Udny Yule' @ 72.249.76.132

\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 & 4 seconds \tabularnewline
R Server & 'George Udny Yule' @ 72.249.76.132 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=22959&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]4 seconds[/C][/ROW]
[ROW][C]R Server[/C][C]'George Udny Yule' @ 72.249.76.132[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=22959&T=0

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=22959&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 time4 seconds
R Server'George Udny Yule' @ 72.249.76.132






Testing Mean with known Variance
sample size27
population variance0.012
sample mean0.1546
null hypothesis about mean0.15
type I error0.05
Z-value0.218197158551618
p-value (one-tailed)0.413637749448374
p-value (two-tailed)0.827275498896748
conclusion for one-tailed test
Do not reject the null hypothesis.
conclusion for two-tailed test
Do not reject the null hypothesis

\begin{tabular}{lllllllll}
\hline
Testing Mean with known Variance \tabularnewline
sample size & 27 \tabularnewline
population variance & 0.012 \tabularnewline
sample mean & 0.1546 \tabularnewline
null hypothesis about mean & 0.15 \tabularnewline
type I error & 0.05 \tabularnewline
Z-value & 0.218197158551618 \tabularnewline
p-value (one-tailed) & 0.413637749448374 \tabularnewline
p-value (two-tailed) & 0.827275498896748 \tabularnewline
conclusion for one-tailed test \tabularnewline
Do not reject the null hypothesis. \tabularnewline
conclusion for two-tailed test \tabularnewline
Do not reject the null hypothesis \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=22959&T=1

[TABLE]
[ROW][C]Testing Mean with known Variance[/C][/ROW]
[ROW][C]sample size[/C][C]27[/C][/ROW]
[ROW][C]population variance[/C][C]0.012[/C][/ROW]
[ROW][C]sample mean[/C][C]0.1546[/C][/ROW]
[ROW][C]null hypothesis about mean[/C][C]0.15[/C][/ROW]
[ROW][C]type I error[/C][C]0.05[/C][/ROW]
[ROW][C]Z-value[/C][C]0.218197158551618[/C][/ROW]
[ROW][C]p-value (one-tailed)[/C][C]0.413637749448374[/C][/ROW]
[ROW][C]p-value (two-tailed)[/C][C]0.827275498896748[/C][/ROW]
[ROW][C]conclusion for one-tailed test[/C][/ROW]
[ROW][C]Do not reject the null hypothesis.[/C][/ROW]
[ROW][C]conclusion for two-tailed test[/C][/ROW]
[ROW][C]Do not reject the null hypothesis[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=22959&T=1

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=22959&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 Mean with known Variance
sample size27
population variance0.012
sample mean0.1546
null hypothesis about mean0.15
type I error0.05
Z-value0.218197158551618
p-value (one-tailed)0.413637749448374
p-value (two-tailed)0.827275498896748
conclusion for one-tailed test
Do not reject the null hypothesis.
conclusion for two-tailed test
Do not reject the null hypothesis


Figures (Output of Computation)

Input Parameters & R Code

Parameters (Session):
par1 = 27 ; par2 = 0.012 ; par3 = 0.1546 ; par4 = 0.15 ; par5 = 0.05 ;
Parameters (R input):
par1 = 27 ; par2 = 0.012 ; par3 = 0.1546 ; par4 = 0.15 ; par5 = 0.05 ;
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)
par5<-as.numeric(par5)
c <- 'NA'
csn <- abs(qnorm(par5))
csn2 <- abs(qnorm(par5/2))
z <- (par3 - par4) / (sqrt(par2/par1))
p <- 1-pnorm(z)
if (par3 == par4)
{
conclusion <- 'Error: the null hypothesis and sample mean must not be equal.'
conclusion2 <- conclusion
} else {
if (p < par5/2)
{
conclusion2 <- 'Reject the null hypothesis'
} else {
conclusion2 <- 'Do not reject the null hypothesis'
}
}
if (p < par5)
{
conclusion <- 'Reject the null hypothesis.'
} else {
conclusion <- 'Do not reject the null hypothesis.'
}
p
conclusion
load(file='createtable')
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,hyperlink('ht_mean_knownvar.htm','Testing Mean with known Variance','learn more about Statistical Hypothesis Testing about the Mean when the Variance is known'),2,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'sample size',header=TRUE)
a<-table.element(a,par1)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'population variance',header=TRUE)
a<-table.element(a,par2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'sample mean',header=TRUE)
a<-table.element(a,par3)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'null hypothesis about mean',header=TRUE)
a<-table.element(a,par4)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'type I error',header=TRUE)
a<-table.element(a,par5)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Z-value',header=TRUE)
a<-table.element(a,z)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'p-value (one-tailed)',header=TRUE)
a<-table.element(a,p)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'p-value (two-tailed)',header=TRUE)
a<-table.element(a,p*2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'conclusion for one-tailed test',2,header=TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,conclusion,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'conclusion for two-tailed test',2,header=TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,conclusion2,2)
a<-table.row.end(a)
a<-table.end(a)
table.save(a,file='mytable.tab')