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Author*Unverified author*
R Software Modulerwasp_hypothesismean2.wasp
Title produced by softwareTesting Mean with known Variance - p-value
Date of computationThu, 13 Nov 2008 01:23:06 -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/t1226564632p76agf33i2t0hwe.htm/, Retrieved Sun, 19 May 2024 10:09:40 +0000
Statistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?pk=24479, Retrieved Sun, 19 May 2024 10:09:40 +0000
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Original text written by user:
IsPrivate?No (this computation is public)
User-defined keywordsjulie govaerts
Estimated Impact173
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] [p value zoeken (p...] [2008-11-13 08:23:06] [ff1af8c6f1c2f1c0e8def9bfc9355be9] [Current]
Feedback Forum
2008-11-16 19:55:23 [Annemiek Hoofman] [reply
De eenzijdige p-value zegt dat er 41.47% kans is dat je je vergist dor te zeggen dat het vetpercentage te hoog is.
2008-11-17 09:06:25 [Ken Wright] [reply
p-value is lager als 50%, dus grote kans dat het niet waar is, en dat je waarschijnlijk je zaak zou verliezen als je voor de rechtbank kwam.
2008-11-18 14:04:38 [Julie Govaerts] [reply
De type I error (= alfafout, en dus de kans dat we ons vergissen bij het verwerpen van de nulhypothese) moet je zelf bepalen (hier bepaald door het management).
De p-value is de kans dat het te wijten is aan toeval. De p-value is dus de werkelijke kans dat u zich vergist.
De werkelijke kans dat we ons vergissen is dus veel groter dan de kans die we ons hadden voorgenomen.
2008-11-18 17:19:33 [72e979bcc364082694890d2eccc1a66f] [reply
We moeten inderdaad de p-waarde zoeken. In de tabel vind je dan bij de 1-sided test dat deze 41% bedraagt. Daaruit kan je concluderen dat er 41% kans is dat je je vergist bij het verwerpen.
De p-waarde ligt ook boven de 5%, we zullen dus niet verwerpen.
2008-11-23 15:24:20 [Hannes Van Hoof] [reply
Hier moet je gebruik maken van de one tailed test, omdat de fraude van de producent maar naar 1 kant kan uitgaan.
Hierbij is de p waarde 41%, dit is de kans dat je je vergist als je klacht indient dat het vetpercentage te hoog is. Deze 41% ligt hoger dan de type 1 fout.

Hieruit kan je dan concluderen dat je best geen klacht indient.
2008-11-23 22:46:56 [Anouk Greeve] [reply
De type I error (alfa-fout) wordt meestal door het management bepaald. In dit geval hebben we deze zelf bepaald.
De p-value is de werkelijke kans dat men zich vergist en deze moeten we inderdaad zoeken. De kans dat men zich vergist, indien men een klacht indient, is 41% (p-value).
De p-value is duidelijk veel groter dan de alfa-fout. De nulhypothese mag niet verworpen worden.
2008-11-24 15:49:02 [Jules De Bruycker] [reply
De waarschijnlijkheid dat de klacht ongerechtvaardigd is, bedraagt 41.36%. Omdat de waarschijnlijkheid (41.36%) groter is dan alfa (5%), is er geen reden om de nulhypothese te verwerpen.De alternatieve hypothese zal dus wel worden verworpen, want je moet oftewel de nulhypothese of de alternatieve hypothese verwerpen. We gaan dus geen klacht indienen.

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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=24479&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=24479&T=0

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=24479&T=0

As an alternative you can also use a 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 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=24479&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=24479&T=1

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=24479&T=1

As an alternative you can also use a 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



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')