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Author's title

Author*The author of this computation has been verified*
R Software Modulerwasp_linear_regression.wasp
Title produced by softwareLinear Regression Graphical Model Validation
Date of computationWed, 17 Nov 2010 08:28:03 +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/Nov/17/t1289982466dcmi6oul73fb822.htm/, Retrieved Thu, 25 Apr 2024 07:22:38 +0000
Statistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?pk=96522, Retrieved Thu, 25 Apr 2024 07:22:38 +0000
QR Codes:

Original text written by user:
IsPrivate?No (this computation is public)
User-defined keywords
Estimated Impact174
Family? (F = Feedback message, R = changed R code, M = changed R Module, P = changed Parameters, D = changed Data)
-     [Linear Regression Graphical Model Validation] [Colombia Coffee -...] [2008-02-26 10:22:06] [74be16979710d4c4e7c6647856088456]
-  M D  [Linear Regression Graphical Model Validation] [ws6vb] [2010-11-13 11:31:05] [c7506ced21a6c0dca45d37c8a93c80e0]
-    D    [Linear Regression Graphical Model Validation] [tt] [2010-11-13 12:51:28] [4a7069087cf9e0eda253aeed7d8c30d6]
-    D      [Linear Regression Graphical Model Validation] [W6tutorial] [2010-11-13 14:33:02] [c7506ced21a6c0dca45d37c8a93c80e0]
F    D          [Linear Regression Graphical Model Validation] [] [2010-11-17 08:28:03] [2e49bff66bb3e1f5d7fa8957e12fbb12] [Current]
Feedback Forum
2010-11-20 13:55:39 [48eb36e2c01435ad7e4ea7854a9d98fe] [reply
De student heeft hier gebruikt gemaakt van de correcte softwaremodule om een lineair regressiemodel op te stellen.

Als reviewer ben ik wel van mening dat de student iets meer aandacht zou moeten besteden aan het bespreken van de onderliggende assumpties. Deze zijn naar mijn mening namelijk niet allemaal voldaan. Zo zien we wel duidelijk dat er geen autocorrelatie (in de autocorrelatie functie en lag plot) bestaat tussen de twee gegevensreeksen (waarmee aan een belangrijke voorwaarde werd voldaan), maar we zien (bvb in Normal QQ plot)ook dat er geen normaalverdeling is, terwijl dit wel een voorwaarde is.

Ook het bespreken van de X en Y variabele zou naar mijn mening (vooral naar de paper toe) iets uitgebreider mogen. Zo zou de student duidelijker kunnen vermelden dat de Y variabele of de te verklaren variabele de verwachtingen van de ouders zijn. De X variabele of verklarende variabele is dan logischerwijze de mate waarin studenten zich slecht voelen wanneer ze slechte resultaten behalen.

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Dataseries X:
2
1
4
2
2
2
2
2
1
4
2
3
2
2
1
3
1
2
4
4
3
2
3
2
2
3
3
2
4
2
2
3
5
2
3
1
2
2
4
2
4
3
2
4
2
2
2
2
2
3
1
2
2
1
5
2
2
2
1
2
2
2
4
2
1
2
2
2
1
2
2
2
3
3
2
2
3
2
2
2
2
2
1
3
2
4
2
1
4
3
2
3
2
3
2
5
3
4
2
2
2
3
4
3
2
2
3
2
2
2
2
3
2
4
1
2
4
2
2
1
1
3
3
1
1
3
1
2
3
2
2
2
2
2
2
4
2
2
3
2
2
4
4
1
3
2
4
2
1
2
2
3
5
2
4
2
2
3
4
Dataseries Y:
1
2
2
2
2
2
2
3
4
2
3
4
4
2
1
1
3
2
3
4
4
4
4
4
2
3
2
4
3
2
3
4
4
5
3
3
4
2
4
2
3
2
2
2
3
3
2
4
4
4
3
1
4
2
3
4
4
2
1
2
2
4
3
2
2
4
4
2
1
2
4
3
4
2
4
1
2
4
4
4
3
2
2
4
3
4
3
1
2
3
4
1
3
3
2
4
4
4
3
2
3
1
3
2
4
3
4
3
3
2
2
4
3
4
1
2
4
2
2
4
5
2
4
2
2
2
2
3
2
4
3
2
2
1
2
4
2
2
4
2
4
5
2
4
3
4
3
2
2
4
3
4
5
3
1
3
4
4
4




Summary of computational transaction
Raw Inputview raw input (R code)
Raw Outputview raw output of R engine
Computing time5 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 & 5 seconds \tabularnewline
R Server & 'Gwilym Jenkins' @ 72.249.127.135 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=96522&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]5 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=96522&T=0

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=96522&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 time5 seconds
R Server'Gwilym Jenkins' @ 72.249.127.135







Simple Linear Regression
StatisticsEstimateS.D.T-STAT (H0: coeff=0)P-value (two-sided)
constant term2.223772564751030.21785464018893810.20759788647340
slope0.2707334089125320.08429525298689523.211727817634300.00160075221693168

\begin{tabular}{lllllllll}
\hline
Simple Linear Regression \tabularnewline
Statistics & Estimate & S.D. & T-STAT (H0: coeff=0) & P-value (two-sided) \tabularnewline
constant term & 2.22377256475103 & 0.217854640188938 & 10.2075978864734 & 0 \tabularnewline
slope & 0.270733408912532 & 0.0842952529868952 & 3.21172781763430 & 0.00160075221693168 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=96522&T=1

[TABLE]
[ROW][C]Simple Linear Regression[/C][/ROW]
[ROW][C]Statistics[/C][C]Estimate[/C][C]S.D.[/C][C]T-STAT (H0: coeff=0)[/C][C]P-value (two-sided)[/C][/ROW]
[ROW][C]constant term[/C][C]2.22377256475103[/C][C]0.217854640188938[/C][C]10.2075978864734[/C][C]0[/C][/ROW]
[ROW][C]slope[/C][C]0.270733408912532[/C][C]0.0842952529868952[/C][C]3.21172781763430[/C][C]0.00160075221693168[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=96522&T=1

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=96522&T=1

As an alternative you can also use a QR Code:  

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

Simple Linear Regression
StatisticsEstimateS.D.T-STAT (H0: coeff=0)P-value (two-sided)
constant term2.223772564751030.21785464018893810.20759788647340
slope0.2707334089125320.08429525298689523.211727817634300.00160075221693168



Parameters (Session):
par1 = 0 ;
Parameters (R input):
par1 = 0 ;
R code (references can be found in the software module):
par1 <- as.numeric(par1)
library(lattice)
z <- as.data.frame(cbind(x,y))
m <- lm(y~x)
summary(m)
bitmap(file='test1.png')
plot(z,main='Scatterplot, lowess, and regression line')
lines(lowess(z),col='red')
abline(m)
grid()
dev.off()
bitmap(file='test2.png')
m2 <- lm(m$fitted.values ~ x)
summary(m2)
z2 <- as.data.frame(cbind(x,m$fitted.values))
names(z2) <- list('x','Fitted')
plot(z2,main='Scatterplot, lowess, and regression line')
lines(lowess(z2),col='red')
abline(m2)
grid()
dev.off()
bitmap(file='test3.png')
m3 <- lm(m$residuals ~ x)
summary(m3)
z3 <- as.data.frame(cbind(x,m$residuals))
names(z3) <- list('x','Residuals')
plot(z3,main='Scatterplot, lowess, and regression line')
lines(lowess(z3),col='red')
abline(m3)
grid()
dev.off()
bitmap(file='test4.png')
m4 <- lm(m$fitted.values ~ m$residuals)
summary(m4)
z4 <- as.data.frame(cbind(m$residuals,m$fitted.values))
names(z4) <- list('Residuals','Fitted')
plot(z4,main='Scatterplot, lowess, and regression line')
lines(lowess(z4),col='red')
abline(m4)
grid()
dev.off()
bitmap(file='test5.png')
myr <- as.ts(m$residuals)
z5 <- as.data.frame(cbind(lag(myr,1),myr))
names(z5) <- list('Lagged Residuals','Residuals')
plot(z5,main='Lag plot')
m5 <- lm(z5)
summary(m5)
abline(m5)
grid()
dev.off()
bitmap(file='test6.png')
hist(m$residuals,main='Residual Histogram',xlab='Residuals')
dev.off()
bitmap(file='test7.png')
if (par1 > 0)
{
densityplot(~m$residuals,col='black',main=paste('Density Plot bw = ',par1),bw=par1)
} else {
densityplot(~m$residuals,col='black',main='Density Plot')
}
dev.off()
bitmap(file='test8.png')
acf(m$residuals,main='Residual Autocorrelation Function')
dev.off()
bitmap(file='test9.png')
qqnorm(x)
qqline(x)
grid()
dev.off()
load(file='createtable')
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,'Simple Linear Regression',5,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Statistics',1,TRUE)
a<-table.element(a,'Estimate',1,TRUE)
a<-table.element(a,'S.D.',1,TRUE)
a<-table.element(a,'T-STAT (H0: coeff=0)',1,TRUE)
a<-table.element(a,'P-value (two-sided)',1,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'constant term',header=TRUE)
a<-table.element(a,m$coefficients[[1]])
sd <- sqrt(vcov(m)[1,1])
a<-table.element(a,sd)
tstat <- m$coefficients[[1]]/sd
a<-table.element(a,tstat)
pval <- 2*(1-pt(abs(tstat),length(x)-2))
a<-table.element(a,pval)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'slope',header=TRUE)
a<-table.element(a,m$coefficients[[2]])
sd <- sqrt(vcov(m)[2,2])
a<-table.element(a,sd)
tstat <- m$coefficients[[2]]/sd
a<-table.element(a,tstat)
pval <- 2*(1-pt(abs(tstat),length(x)-2))
a<-table.element(a,pval)
a<-table.row.end(a)
a<-table.end(a)
table.save(a,file='mytable.tab')