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Author's title

Author*Unverified author*
R Software Modulerwasp_autocorrelation.wasp
Title produced by software(Partial) Autocorrelation Function
Date of computationWed, 03 Dec 2008 00:40:58 -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/Dec/03/t1228290126bo1tmok4sj32atf.htm/, Retrieved Sun, 19 May 2024 07:07:21 +0000
Statistical Computations at FreeStatistics.org, Office for Research Development and Education, URL https://freestatistics.org/blog/index.php?pk=28552, Retrieved Sun, 19 May 2024 07:07:21 +0000
QR Codes:

Original text written by user:
IsPrivate?No (this computation is public)
User-defined keywords
Estimated Impact217
Family? (F = Feedback message, R = changed R code, M = changed R Module, P = changed Parameters, D = changed Data)
F       [(Partial) Autocorrelation Function] [] [2008-12-03 07:40:58] [e02910eed3830f1815f587e12f46cbdb] [Current]
-   PD    [(Partial) Autocorrelation Function] [] [2008-12-06 11:35:59] [996314793dac993597edc1ca2281ff39]
Feedback Forum
2008-12-06 10:57:12 [Angelique Van de Vijver] [reply
goede berekening en juiste vaststellingen van de student, wel weinig uitleg.
We zien op de ACF inderdaad een langzaam dalend patroon wat dus op een langetermijntrend wijst. We zien hier een positieve autocorrelatie : Het verleden van de reeks geeft ons informatie over de daaropvolgende waarden. Waarden worden bepaald door het verleden( als de vorige waarde groot is, zal de huidige waarde ook groot zijn). We zien ook dat de meeste balkjes zich boven het 95% betrouwbaarheidsinterval bevinden en dus significant verschillend van 0 zijn. De laatste balkjes vallen onder het betrouwbaarheidsinterval en zijn dus niet significant verschillend van 0.
Hier moeten we niet-seizoenaal differentieren om zo tot een stationaire tijdreeks te komen.
2008-12-06 11:41:09 [Angelique Van de Vijver] [reply
Student heeft wel een verkeerde berekening gemaakt, merk ik nu op. Number of time lags stond bij haar op default. Ik heb de berekening opnieuw gemaakt met number of time lags gelijk aan 36:
http://www.freestatistics.org/blog/date/2008/Dec/06/t1228563476sucjulrt1w2cl7d.htm
Nu krijgen we wel een andere ACF. Er is wel nog altijd een langzaam dalend verloop en dus een langetermijntrend. We moeten dus nog altijd niet-seizoenaal differentiëren om deze tren eruit te halen.

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Dataseries X:
118,4
121,4
128,8
131,7
141,7
142,9
139,4
134,7
125,0
113,6
111,5
108,5
112,3
116,6
115,5
120,1
132,9
128,1
129,3
132,5
131,0
124,9
120,8
122,0
122,1
127,4
135,2
137,3
135,0
136,0
138,4
134,7
138,4
133,9
133,6
141,2
151,8
155,4
156,6
161,6
160,7
156,0
159,5
168,7
169,9
169,9
185,9
190,8
195,8
211,9
227,1
251,3
256,7
251,9
251,2
270,3
267,2
243,0
229,9
187,2




Summary of computational transaction
Raw Inputview raw input (R code)
Raw Outputview raw output of R engine
Computing time0 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 & 0 seconds \tabularnewline
R Server & 'Gwilym Jenkins' @ 72.249.127.135 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=28552&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]0 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=28552&T=0

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=28552&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 time0 seconds
R Server'Gwilym Jenkins' @ 72.249.127.135







Autocorrelation Function
Time lag kACF(k)T-STATP-value
10.9665477.48680
20.904777.00830
30.8319776.44450
40.7478445.79280
50.6663055.16121e-06
60.5890384.56271.3e-05
70.5124663.96959.8e-05
80.4400783.40880.000586
90.3776722.92540.002425
100.3219842.49410.007701
110.2743882.12540.01884
120.2309621.7890.039329
130.187591.45310.075708
140.1483651.14920.127511
150.1109320.85930.196805
160.0760070.58870.27912
170.0462450.35820.36072

\begin{tabular}{lllllllll}
\hline
Autocorrelation Function \tabularnewline
Time lag k & ACF(k) & T-STAT & P-value \tabularnewline
1 & 0.966547 & 7.4868 & 0 \tabularnewline
2 & 0.90477 & 7.0083 & 0 \tabularnewline
3 & 0.831977 & 6.4445 & 0 \tabularnewline
4 & 0.747844 & 5.7928 & 0 \tabularnewline
5 & 0.666305 & 5.1612 & 1e-06 \tabularnewline
6 & 0.589038 & 4.5627 & 1.3e-05 \tabularnewline
7 & 0.512466 & 3.9695 & 9.8e-05 \tabularnewline
8 & 0.440078 & 3.4088 & 0.000586 \tabularnewline
9 & 0.377672 & 2.9254 & 0.002425 \tabularnewline
10 & 0.321984 & 2.4941 & 0.007701 \tabularnewline
11 & 0.274388 & 2.1254 & 0.01884 \tabularnewline
12 & 0.230962 & 1.789 & 0.039329 \tabularnewline
13 & 0.18759 & 1.4531 & 0.075708 \tabularnewline
14 & 0.148365 & 1.1492 & 0.127511 \tabularnewline
15 & 0.110932 & 0.8593 & 0.196805 \tabularnewline
16 & 0.076007 & 0.5887 & 0.27912 \tabularnewline
17 & 0.046245 & 0.3582 & 0.36072 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=28552&T=1

[TABLE]
[ROW][C]Autocorrelation Function[/C][/ROW]
[ROW][C]Time lag k[/C][C]ACF(k)[/C][C]T-STAT[/C][C]P-value[/C][/ROW]
[ROW][C]1[/C][C]0.966547[/C][C]7.4868[/C][C]0[/C][/ROW]
[ROW][C]2[/C][C]0.90477[/C][C]7.0083[/C][C]0[/C][/ROW]
[ROW][C]3[/C][C]0.831977[/C][C]6.4445[/C][C]0[/C][/ROW]
[ROW][C]4[/C][C]0.747844[/C][C]5.7928[/C][C]0[/C][/ROW]
[ROW][C]5[/C][C]0.666305[/C][C]5.1612[/C][C]1e-06[/C][/ROW]
[ROW][C]6[/C][C]0.589038[/C][C]4.5627[/C][C]1.3e-05[/C][/ROW]
[ROW][C]7[/C][C]0.512466[/C][C]3.9695[/C][C]9.8e-05[/C][/ROW]
[ROW][C]8[/C][C]0.440078[/C][C]3.4088[/C][C]0.000586[/C][/ROW]
[ROW][C]9[/C][C]0.377672[/C][C]2.9254[/C][C]0.002425[/C][/ROW]
[ROW][C]10[/C][C]0.321984[/C][C]2.4941[/C][C]0.007701[/C][/ROW]
[ROW][C]11[/C][C]0.274388[/C][C]2.1254[/C][C]0.01884[/C][/ROW]
[ROW][C]12[/C][C]0.230962[/C][C]1.789[/C][C]0.039329[/C][/ROW]
[ROW][C]13[/C][C]0.18759[/C][C]1.4531[/C][C]0.075708[/C][/ROW]
[ROW][C]14[/C][C]0.148365[/C][C]1.1492[/C][C]0.127511[/C][/ROW]
[ROW][C]15[/C][C]0.110932[/C][C]0.8593[/C][C]0.196805[/C][/ROW]
[ROW][C]16[/C][C]0.076007[/C][C]0.5887[/C][C]0.27912[/C][/ROW]
[ROW][C]17[/C][C]0.046245[/C][C]0.3582[/C][C]0.36072[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=28552&T=1

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=28552&T=1

As an alternative you can also use a QR Code:  

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

Autocorrelation Function
Time lag kACF(k)T-STATP-value
10.9665477.48680
20.904777.00830
30.8319776.44450
40.7478445.79280
50.6663055.16121e-06
60.5890384.56271.3e-05
70.5124663.96959.8e-05
80.4400783.40880.000586
90.3776722.92540.002425
100.3219842.49410.007701
110.2743882.12540.01884
120.2309621.7890.039329
130.187591.45310.075708
140.1483651.14920.127511
150.1109320.85930.196805
160.0760070.58870.27912
170.0462450.35820.36072







Partial Autocorrelation Function
Time lag kPACF(k)T-STATP-value
10.9665477.48680
2-0.447564-3.46680.00049
3-0.025285-0.19590.422691
4-0.179163-1.38780.085167
50.1428051.10620.136536
6-0.063118-0.48890.313343
7-0.052296-0.40510.343428
8-0.013999-0.10840.457005
90.0960530.7440.229884
10-0.043902-0.34010.367498
110.0398220.30850.3794
12-0.108762-0.84250.201437
13-0.022603-0.17510.430802
140.0283140.21930.413572
15-0.047531-0.36820.35702
160.0127240.09860.460909
170.0042970.03330.486779

\begin{tabular}{lllllllll}
\hline
Partial Autocorrelation Function \tabularnewline
Time lag k & PACF(k) & T-STAT & P-value \tabularnewline
1 & 0.966547 & 7.4868 & 0 \tabularnewline
2 & -0.447564 & -3.4668 & 0.00049 \tabularnewline
3 & -0.025285 & -0.1959 & 0.422691 \tabularnewline
4 & -0.179163 & -1.3878 & 0.085167 \tabularnewline
5 & 0.142805 & 1.1062 & 0.136536 \tabularnewline
6 & -0.063118 & -0.4889 & 0.313343 \tabularnewline
7 & -0.052296 & -0.4051 & 0.343428 \tabularnewline
8 & -0.013999 & -0.1084 & 0.457005 \tabularnewline
9 & 0.096053 & 0.744 & 0.229884 \tabularnewline
10 & -0.043902 & -0.3401 & 0.367498 \tabularnewline
11 & 0.039822 & 0.3085 & 0.3794 \tabularnewline
12 & -0.108762 & -0.8425 & 0.201437 \tabularnewline
13 & -0.022603 & -0.1751 & 0.430802 \tabularnewline
14 & 0.028314 & 0.2193 & 0.413572 \tabularnewline
15 & -0.047531 & -0.3682 & 0.35702 \tabularnewline
16 & 0.012724 & 0.0986 & 0.460909 \tabularnewline
17 & 0.004297 & 0.0333 & 0.486779 \tabularnewline
\hline
\end{tabular}
%Source: https://freestatistics.org/blog/index.php?pk=28552&T=2

[TABLE]
[ROW][C]Partial Autocorrelation Function[/C][/ROW]
[ROW][C]Time lag k[/C][C]PACF(k)[/C][C]T-STAT[/C][C]P-value[/C][/ROW]
[ROW][C]1[/C][C]0.966547[/C][C]7.4868[/C][C]0[/C][/ROW]
[ROW][C]2[/C][C]-0.447564[/C][C]-3.4668[/C][C]0.00049[/C][/ROW]
[ROW][C]3[/C][C]-0.025285[/C][C]-0.1959[/C][C]0.422691[/C][/ROW]
[ROW][C]4[/C][C]-0.179163[/C][C]-1.3878[/C][C]0.085167[/C][/ROW]
[ROW][C]5[/C][C]0.142805[/C][C]1.1062[/C][C]0.136536[/C][/ROW]
[ROW][C]6[/C][C]-0.063118[/C][C]-0.4889[/C][C]0.313343[/C][/ROW]
[ROW][C]7[/C][C]-0.052296[/C][C]-0.4051[/C][C]0.343428[/C][/ROW]
[ROW][C]8[/C][C]-0.013999[/C][C]-0.1084[/C][C]0.457005[/C][/ROW]
[ROW][C]9[/C][C]0.096053[/C][C]0.744[/C][C]0.229884[/C][/ROW]
[ROW][C]10[/C][C]-0.043902[/C][C]-0.3401[/C][C]0.367498[/C][/ROW]
[ROW][C]11[/C][C]0.039822[/C][C]0.3085[/C][C]0.3794[/C][/ROW]
[ROW][C]12[/C][C]-0.108762[/C][C]-0.8425[/C][C]0.201437[/C][/ROW]
[ROW][C]13[/C][C]-0.022603[/C][C]-0.1751[/C][C]0.430802[/C][/ROW]
[ROW][C]14[/C][C]0.028314[/C][C]0.2193[/C][C]0.413572[/C][/ROW]
[ROW][C]15[/C][C]-0.047531[/C][C]-0.3682[/C][C]0.35702[/C][/ROW]
[ROW][C]16[/C][C]0.012724[/C][C]0.0986[/C][C]0.460909[/C][/ROW]
[ROW][C]17[/C][C]0.004297[/C][C]0.0333[/C][C]0.486779[/C][/ROW]
[/TABLE]
Source: https://freestatistics.org/blog/index.php?pk=28552&T=2

Globally Unique Identifier (entire table): ba.freestatistics.org/blog/index.php?pk=28552&T=2

As an alternative you can also use a QR Code:  

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

Partial Autocorrelation Function
Time lag kPACF(k)T-STATP-value
10.9665477.48680
2-0.447564-3.46680.00049
3-0.025285-0.19590.422691
4-0.179163-1.38780.085167
50.1428051.10620.136536
6-0.063118-0.48890.313343
7-0.052296-0.40510.343428
8-0.013999-0.10840.457005
90.0960530.7440.229884
10-0.043902-0.34010.367498
110.0398220.30850.3794
12-0.108762-0.84250.201437
13-0.022603-0.17510.430802
140.0283140.21930.413572
15-0.047531-0.36820.35702
160.0127240.09860.460909
170.0042970.03330.486779



Parameters (Session):
par1 = Default ; par2 = 1 ; par3 = 0 ; par4 = 0 ; par5 = 12 ;
Parameters (R input):
par1 = Default ; par2 = 1 ; par3 = 0 ; par4 = 0 ; par5 = 12 ;
R code (references can be found in the software module):
if (par1 == 'Default') {
par1 = 10*log10(length(x))
} else {
par1 <- as.numeric(par1)
}
par2 <- as.numeric(par2)
par3 <- as.numeric(par3)
par4 <- as.numeric(par4)
par5 <- as.numeric(par5)
if (par2 == 0) {
x <- log(x)
} else {
x <- (x ^ par2 - 1) / par2
}
if (par3 > 0) x <- diff(x,lag=1,difference=par3)
if (par4 > 0) x <- diff(x,lag=par5,difference=par4)
bitmap(file='pic1.png')
racf <- acf(x,par1,main='Autocorrelation',xlab='lags',ylab='ACF')
dev.off()
bitmap(file='pic2.png')
rpacf <- pacf(x,par1,main='Partial Autocorrelation',xlab='lags',ylab='PACF')
dev.off()
(myacf <- c(racf$acf))
(mypacf <- c(rpacf$acf))
lengthx <- length(x)
sqrtn <- sqrt(lengthx)
load(file='createtable')
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,'Autocorrelation Function',4,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Time lag k',header=TRUE)
a<-table.element(a,hyperlink('basics.htm','ACF(k)','click here for more information about the Autocorrelation Function'),header=TRUE)
a<-table.element(a,'T-STAT',header=TRUE)
a<-table.element(a,'P-value',header=TRUE)
a<-table.row.end(a)
for (i in 2:(par1+1)) {
a<-table.row.start(a)
a<-table.element(a,i-1,header=TRUE)
a<-table.element(a,round(myacf[i],6))
mytstat <- myacf[i]*sqrtn
a<-table.element(a,round(mytstat,4))
a<-table.element(a,round(1-pt(abs(mytstat),lengthx),6))
a<-table.row.end(a)
}
a<-table.end(a)
table.save(a,file='mytable.tab')
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,'Partial Autocorrelation Function',4,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Time lag k',header=TRUE)
a<-table.element(a,hyperlink('basics.htm','PACF(k)','click here for more information about the Partial Autocorrelation Function'),header=TRUE)
a<-table.element(a,'T-STAT',header=TRUE)
a<-table.element(a,'P-value',header=TRUE)
a<-table.row.end(a)
for (i in 1:par1) {
a<-table.row.start(a)
a<-table.element(a,i,header=TRUE)
a<-table.element(a,round(mypacf[i],6))
mytstat <- mypacf[i]*sqrtn
a<-table.element(a,round(mytstat,4))
a<-table.element(a,round(1-pt(abs(mytstat),lengthx),6))
a<-table.row.end(a)
}
a<-table.end(a)
table.save(a,file='mytable1.tab')