Introdução

O banco de dados deste trabalho estĆ” disponĆ­vel no software Rstudio, ā€œheadā€ que traz em seu interior 29 observaƧƵes de aquiferos, contendo coodenadas ā€œx, yā€ e os dados em questĆ£o ā€œzā€ em determinada regiĆ£o de estudo.

Vamos aos cƔlculos

Para da início as atividades, se necessÔrio fazer a istalação dos pacotes (geoR) e (MASS), caso não se tenha previamente instalado em sua maquina, e a requerição dos mesmos.

if(!require(geoR)){install.packages("geoR")}
## Loading required package: geoR
## Warning: package 'geoR' was built under R version 3.4.4
## --------------------------------------------------------------
##  Analysis of Geostatistical Data
##  For an Introduction to geoR go to http://www.leg.ufpr.br/geoR
##  geoR version 1.7-5.2.1 (built on 2016-05-02) is now loaded
## --------------------------------------------------------------
if(!require(MASS)){install.packages("MASS")}
## Loading required package: MASS
## Warning: package 'MASS' was built under R version 3.4.4

Sobre os Dados

Os dados disponĆ­veis no software Rstudio foram reorganizados e salvos em formato ā€œtxtā€, afim de se ter uma melhor visualização das informaƧƵes.

setwd("F:/Estatistica Espacial")
dados <- read.table("BDinf.txt", head=T); dados
##        x     y    z
## 1   6.86  6.41 1061
## 2   4.32  5.02 1194
## 3   5.98  6.01 1117
## 4  11.61  4.99  880
## 5   5.52  3.79 1202
## 6  10.87  8.27  757
## 7   8.61  3.92 1038
## 8  12.64  6.77  817
## 9  14.70 10.43  630
## 10 13.91 10.91  617
## 11  9.47  5.62  986
## 12 14.36 11.03  625
## 13  8.99  7.31  840
## 14 11.93  6.78  847
## 15 11.75 10.80  645
## 16 13.23 10.18  662
## 17 13.56  9.74  685
## 18  8.06  5.76 1023
## 19 10.95  3.72  998
## 20 14.71 11.41  584
## 21 16.27  7.27  611
## 22 12.33  6.87  847
## 23 13.01  7.05  745
## 24 13.56  7.42  725
## 25 13.76  8.35  688
## 26 12.54  9.04  676
## 27  8.97  8.60  768
## 28  9.22  8.55  782
## 29  9.64  3.38 1022

InformaƧƵes dos dados

Leitura dos dados

head(dados)
##       x    y    z
## 1  6.86 6.41 1061
## 2  4.32 5.02 1194
## 3  5.98 6.01 1117
## 4 11.61 4.99  880
## 5  5.52 3.79 1202
## 6 10.87 8.27  757

Dimensão dos dados

dim(dados)
## [1] 29  3

Nome das colunas dos dados

colnames(dados)
## [1] "x" "y" "z"

Quantidade de observaƧƵes dos dados

rownames(dados)
##  [1] "1"  "2"  "3"  "4"  "5"  "6"  "7"  "8"  "9"  "10" "11" "12" "13" "14"
## [15] "15" "16" "17" "18" "19" "20" "21" "22" "23" "24" "25" "26" "27" "28"
## [29] "29"

Dimenção dobanco de dados

dimnames(dados)
## [[1]]
##  [1] "1"  "2"  "3"  "4"  "5"  "6"  "7"  "8"  "9"  "10" "11" "12" "13" "14"
## [15] "15" "16" "17" "18" "19" "20" "21" "22" "23" "24" "25" "26" "27" "28"
## [29] "29"
## 
## [[2]]
## [1] "x" "y" "z"

AnƔlise exploratoria dos dados

SerĆ” dado o nome de ā€œINFā€ para informação dos dados.

INF <-as.geodata(dados)

Resumo dos dados

AtravĆ©s do comando Summary, temos uma sĆ©rie de informaƧƵes sobre os dados, Ou seja, o valor maximo e minimo das coodenadas, a distĆ¢ncia minima e mĆ”xima entre as observaƧƵes, e mĆ©dia e etc…

summary(INF)
## Number of data points: 29 
## 
## Coordinates summary
##         x     y
## min  4.32  3.38
## max 16.27 11.41
## 
## Distance summary
##       min       max 
##  0.254951 12.197713 
## 
## Data summary
##     Min.  1st Qu.   Median     Mean  3rd Qu.     Max. 
##  584.000  676.000  782.000  830.069  998.000 1202.000

visualização grÔfica dos dados

GrÔfico dos dados originais sem adição de efeito, para visualizar seu respectivo comportamento.

plot(INF)

GrÔfico dos dados originais sem adição de efeito, com a linha de ajuste de estacionÔriedade.

plot(INF, low=T)

GrĆ”fico dos dados com efeito de tendĆŖncia de primeira ordem ā€œ1stā€

plot(INF, low=T, trend="1st")

Adição de algumas perfumarias para melhorar a estĆ©tica do grĆ”fico dos dados com efeito de tendĆŖncia de primeira ordem ā€œ1stā€, com adição dos quintis.

args(points.geodata)
## function (x, coords = x$coords, data = x$data, data.col = 1, 
##     borders = x$borders, pt.divide = c("data.proportional", "rank.proportional", 
##         "quintiles", "quartiles", "deciles", "equal"), lambda = 1, 
##     trend = "cte", abs.residuals = FALSE, weights.divide = "units.m", 
##     cex.min, cex.max, cex.var, pch.seq, col.seq, add.to.plot = FALSE, 
##     x.leg, y.leg = NULL, dig.leg = 2, round.quantiles = FALSE, 
##     permute = FALSE, ...) 
## NULL
points(INF, trend="1st", pt.div="quint", perm=T)

Variograma

Variograma dos dados originais sem adição de efeito e seu respectivo grÔfico.

INFO <- variog(INF)
## variog: computing omnidirectional variogram
plot(INFO)

Variograma com efeito de tendĆŖncia de primeira ordem ā€œ1stā€ e seu respectivo grĆ”fico.

INFO <- variog(INF, trend = "1st")
## variog: computing omnidirectional variogram
plot(INFO)

Variograma com efeito de tendência na coordenada X e seu respectivo grÔfico.

INFO <- variog(INF,trend = ~coords[,1])
## variog: computing omnidirectional variogram
plot(INFO)

Variograma com efeito de tendência na coordenada y e seu respectivo grÔfico.

INFO <- variog(INF,trend = ~coords[,2])
## variog: computing omnidirectional variogram
plot(INFO)

Variograma com 1/3 da distância mÔxima, e seu respectivo grÔfico.

INFO <- variog(INF, max.dist=5)
## variog: computing omnidirectional variogram
plot(INFO)

O variograma com efeito de tendĆŖncia de primeira ordem ā€œ1stā€, mostra aparentemente um comportamento com maior influĆŖncia com efeito de tendencia de primeira ordem.

INFO1 <- variog(INF, trend = "1st")
## variog: computing omnidirectional variogram
plot(INFO1)

Envelope simulado

GrĆ”fico do envelope simulado para verificar se existe pontos fora dos limites de predição ā€œEnvelopeā€.

INFO1.env <- variog.mc.env(INF, obj=INFO)
## variog.env: generating 99 simulations by permutating data values
## variog.env: computing the empirical variogram for the 99 simulations
## variog.env: computing the envelops
plot(INFO, env=INFO1.env)
lines(INFO1.env)

MƔxima VerosimilhanƧa

Ajuste dos modelos pelo mƩtodo de mƔxima verosimilhanƧa, afim de encontrar um melhor modelo que se adeque com os dados.

Função wave

Ajuste do modelo inicial ā€œml1ā€ sem efeito de tendĆŖncia e sem trasformação.

ml1 <- likfit(INF, ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml1
## likfit: estimated model parameters:
##        beta       tausq     sigmasq         phi 
## "   865.85" "     0.00" "103420.24" "    79.81" 
## Practical Range with cor=0.05 for asymptotic range: 239.0881
## 
## likfit: maximised log-likelihood = -154.5

Valores de AIC e BIC respectivamente para o ml1

aicbic1=c(ml1$AIC,ml1$BIC);aicbic1
## [1] 317.0398 322.5090

Ajuste do modelo ā€œml2ā€ sem efeito de tendĆŖncia e com Trasformação.

ml2 <- likfit(INF,lam=0, ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml2
## likfit: estimated model parameters:
##      beta     tausq   sigmasq       phi 
## " 6.6966" " 0.0000" " 0.1431" "76.3245" 
## Practical Range with cor=0.05 for asymptotic range: 228.6476
## 
## likfit: maximised log-likelihood = -153.8

Valores de AIC e BIC respectivamente para o ml2

aicbic2=c(ml2$AIC,ml2$BIC);aicbic2
## [1] 315.5280 320.9972

Ajuste do modelo ā€œml3ā€com efeito de tendĆŖncia de primeira ordem ā€œ1stā€ e sem trasformação.

ml3 <- likfit(INF, trend="1st", ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml3
## likfit: estimated model parameters:
##      beta0      beta1      beta2      tausq    sigmasq        phi 
## "1536.547" " -37.656" " -39.559" "   0.000" "1401.524" "   1.705" 
## Practical Range with cor=0.05 for asymptotic range: 5.107397
## 
## likfit: maximised log-likelihood = -139.8

Valores de AIC e BIC respectivamente para o ml3

aicbic3=c(ml3$AIC,ml3$BIC);aicbic3
## [1] 291.5319 299.7357

Ajuste do modelo ā€œml4ā€com efeito de tendĆŖncia de primeira ordem ā€œ1stā€ com trasformação.

ml4 <- likfit(INF, trend="1st",lam=0, ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml4
## likfit: estimated model parameters:
##     beta0     beta1     beta2     tausq   sigmasq       phi 
## " 7.5220" "-0.0426" "-0.0487" " 0.0000" " 0.0015" " 1.0496" 
## Practical Range with cor=0.05 for asymptotic range: 3.144218
## 
## likfit: maximised log-likelihood = -138

Valores de AIC e BIC respectivamente para o ml4

aicbic4=c(ml4$AIC,ml4$BIC);aicbic4
## [1] 288.0426 296.2464

Ajuste do modelo ā€œml5ā€ com efeito de tendĆŖncia na coordenada x sem trasformação.

ml5 <- likfit(INF,trend = ~coords[,1], ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml5
## likfit: estimated model parameters:
##      beta0      beta1      tausq    sigmasq        phi 
## " 1336.50" "  -44.75" "    0.00" "19806.10" "   22.26" 
## Practical Range with cor=0.05 for asymptotic range: 66.69733
## 
## likfit: maximised log-likelihood = -148.1

Valores de AIC e BIC respectivamente para o ml5

aicbic5=c(ml5$AIC,ml5$BIC);aicbic5
## [1] 306.2378 313.0743

Ajuste do modelo ā€œml6ā€ com efeito de tendĆŖncia na coordenada x com trasformação.

ml6 <- likfit(INF,trend = ~coords[,1],lam=0, ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml6
## likfit: estimated model parameters:
##     beta0     beta1     tausq   sigmasq       phi 
## " 7.2535" "-0.0523" " 0.0000" " 0.0284" "21.4481" 
## Practical Range with cor=0.05 for asymptotic range: 64.25264
## 
## likfit: maximised log-likelihood = -147.8

Valores de AIC e BIC respectivamente para o ml6

aicbic6=c(ml6$AIC,ml6$BIC);aicbic6
## [1] 305.5666 312.4031

Ajuste do modelo ā€œml7ā€ com efeito de tendĆŖncia na coordenada y sem trasformação.

ml7 <- likfit(INF,trend = ~coords[,2], ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml7
## likfit: estimated model parameters:
##      beta0      beta1      tausq    sigmasq        phi 
## " 1194.34" "  -46.80" "    0.00" "38730.95" "   40.83" 
## Practical Range with cor=0.05 for asymptotic range: 122.3032
## 
## likfit: maximised log-likelihood = -149.6

Valores de AIC e BIC respectivamente para o ml7

aicbic7=c(ml7$AIC,ml7$BIC);aicbic7
## [1] 309.1024 315.9388

Ajuste do modelo ā€œml8ā€ com efeito de tendĆŖncia na coordenada y com trasformação.

ml8 <- likfit(INF,trend = ~coords[,2],lam=0, ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml8
## likfit: estimated model parameters:
##     beta0     beta1     tausq   sigmasq       phi 
## " 7.0961" "-0.0565" " 0.0000" " 0.0502" "36.5207" 
## Practical Range with cor=0.05 for asymptotic range: 109.4063
## 
## likfit: maximised log-likelihood = -148.7

Valores de AIC e BIC respectivamente para o ml8

aicbic8=c(ml8$AIC,ml8$BIC);aicbic8
## [1] 307.4990 314.3354

Função matern

Ajuste do modelo inicial ā€œml9ā€ sem efeito de tendĆŖncia e sem trasformação.

ml9 <- likfit(INF, ini=c(343145.5 , 2.54 ),nug= 0, kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml9
## likfit: estimated model parameters:
##        beta       tausq     sigmasq         phi 
## "  783.652" "  564.608" "50871.521" "    1.305" 
## Practical Range with cor=0.05 for asymptotic range: 14.53213
## 
## likfit: maximised log-likelihood = -150.7

Valores de AIC e BIC respectivamente para o ml9

aicbic9=c(ml9$AIC,ml9$BIC);aicbic9
## [1] 309.4885 314.9577

Ajuste do modelo ā€œml10ā€ sem efeito de tendĆŖncia e com Trasformação.

ml10 <- likfit(INF,lam=0, ini=c(343145.5 , 2.54 ),nug= 0, kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml10
## likfit: estimated model parameters:
##     beta    tausq  sigmasq      phi 
## "6.4173" "0.0011" "0.3442" "2.4725" 
## Practical Range with cor=0.05 for asymptotic range: 27.52899
## 
## likfit: maximised log-likelihood = -152.2

Valores de AIC e BIC respectivamente para o ml10

aicbic10=c(ml10$AIC,ml10$BIC);aicbic10
## [1] 312.3285 317.7977

Ajuste do modelo ā€œml11ā€com efeito de tendĆŖncia de primeira ordem ā€œ1stā€ e sem trasformação.

ml11 <- likfit(INF, trend="1st", ini=c(343145.5 , 2.54 ),nug= 0, kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml11
## likfit: estimated model parameters:
##     beta0     beta1     beta2     tausq   sigmasq       phi 
## "1515.77" " -35.89" " -38.77" "1561.09" "   0.00" "   0.00" 
## Practical Range with cor=0.05 for asymptotic range: 0.0001159668
## 
## likfit: maximised log-likelihood = -147.8

Valores de AIC e BIC respectivamente para o ml11

aicbic11=c(ml11$AIC,ml11$BIC);aicbic11
## [1] 307.5395 315.7432

Ajuste do modelo ā€œml12ā€com efeito de tendĆŖncia de primeira ordem ā€œ1stā€ com trasformação.

ml12 <- likfit(INF, trend="1st",lam=0, ini=c(343145.5 , 2.54 ),nug= 0, 
               kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml12
## likfit: estimated model parameters:
##     beta0     beta1     beta2     tausq   sigmasq       phi 
## " 7.5057" "-0.0401" "-0.0489" " 0.0017" " 0.0000" " 0.0000" 
## Practical Range with cor=0.05 for asymptotic range: 0.0001159668
## 
## likfit: maximised log-likelihood = -142.7

Valores de AIC e BIC respectivamente para o ml12

aicbic12=c(ml12$AIC,ml12$BIC);aicbic12
## [1] 297.4945 305.6983

Ajuste do modelo ā€œml13ā€ com efeito de tendĆŖncia na coordenada x sem trasformação.

ml13 <- likfit(INF,trend = ~coords[,1], ini=c(343145.5 , 2.54 ),nug= 0,
               kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml13
## likfit: estimated model parameters:
##        beta0        beta1        tausq      sigmasq          phi 
## " 1306.8927" "  -44.6548" "  555.9753" "12223.2661" "    0.9811" 
## Practical Range with cor=0.05 for asymptotic range: 10.92419
## 
## likfit: maximised log-likelihood = -147.5

Valores de AIC e BIC respectivamente para o ml13

aicbic13=c(ml13$AIC,ml13$BIC);aicbic13
## [1] 304.9874 311.8239

Ajuste do modelo ā€œml14ā€ com efeito de tendĆŖncia na coordenada x com trasformação.

ml14 <- likfit(INF,trend = ~coords[,1],lam=0, ini=c(343145.5 , 2.54 ),nug= 0,
               kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml14
## likfit: estimated model parameters:
##     beta0     beta1     tausq   sigmasq       phi 
## " 7.2357" "-0.0533" " 0.0008" " 0.0181" " 1.0026" 
## Practical Range with cor=0.05 for asymptotic range: 11.16285
## 
## likfit: maximised log-likelihood = -147

Valores de AIC e BIC respectivamente para o ml14

aicbic14=c(ml14$AIC,ml14$BIC);aicbic14
## [1] 303.9325 310.7690

Ajuste do modelo ā€œml15ā€ com efeito de tendĆŖncia na coordenada y sem trasformação.

ml15 <- likfit(INF,trend = ~coords[,2], ini=c(343145.5 , 2.54 ),nug= 0,
               kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml15
## likfit: estimated model parameters:
##        beta0        beta1        tausq      sigmasq          phi 
## " 1140.5829" "  -45.2068" "  523.3132" "19657.4201" "    0.9958" 
## Practical Range with cor=0.05 for asymptotic range: 11.0876
## 
## likfit: maximised log-likelihood = -149.1

Valores de AIC e BIC respectivamente para o ml15

aicbic15=c(ml15$AIC,ml15$BIC);aicbic15
## [1] 308.1299 314.9664

Ajuste do modelo ā€œml16ā€ com efeito de tendĆŖncia na coordenada y com trasformação.

ml16 <- likfit(INF,trend = ~coords[,2],lam=0, ini=c(343145.5 , 2.54 ),nug= 0,
               kappa = 9.86)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml16
## likfit: estimated model parameters:
##     beta0     beta1     tausq   sigmasq       phi 
## " 7.0367" "-0.0541" " 0.0008" " 0.0281" " 1.0085" 
## Practical Range with cor=0.05 for asymptotic range: 11.22885
## 
## likfit: maximised log-likelihood = -148.6

Valores de AIC e BIC respectivamente para o ml16

aicbic16=c(ml16$AIC,ml16$BIC);aicbic16
## [1] 307.2130 314.0495

TABELA: Mostra os valores de AIC e BIC dos betas, do tau sigma phi, para os respectivos modelos. Tem-se como base a aceitação do modelo pelo critério de menor AIC ou BIC.

Modelos AIC BIC Beta0 Beta1 Beta2 Tau Sigma Phi
ml1 317.0398 322.5090 865.85 —- —- 0.00 103420.24 79.81
ml2 315.5280 320.9972 6.6966 —- —- 0.00 0.1431 76.32
ml3 291.5319 299.7357 1536.55 -37.656 -39.559 0.00 1401.524 1.705
ml4 288.0426 296.2464 7.5220 -0.0426 -0.0487 0.00 0.0015 1.0496
ml5 306.2378 313.0743 1336.50 -44.75 —- 0.00 19806.10 22.26
ml6 305.5566 312.4031 7.2535 -0.0523 —- 0.00 0.0284 21.4481
ml7 309.1024 315.9388 1194.34 -46.80 —- 0.00 38730.95 40.83
ml8 307.4990 314.3354 7.0961 -0.0565 —- 0.00 0.0502 36.5207
ml9 309.4885 314.9577 783.652 —- —- 0.00 50871.521 1.305
ml10 312.3285 317.7977 6.4173 —- —- 0.00 0.3442 2.4725
ml11 307.5395 315.7432 1515.77 -35.89 -38.77 1561.09 0.00 0.00
ml12 297.4945 305.6983 7.5057 -0.0401 -0.0489 0.0017 0.00 0.00
ml13 304.9874 311.8239 1306.89 -44.655 —- 555.975 12223.266 0.9811
ml14 303.9325 310.7690 7.2357 -0.0533 —- 0.0008 0.0181 1.0026
ml15 308.1299 314.9664 1140.59 -45.207 —- 523.31 19657.32 19657.4
ml16 307.2131 314.0495 7.0367 -0.0541 —- 0.0008 0.0281 1.0085

Melhor modelo

O melhor modelo escolhido foi por meio do critƩrio do menor AIC, portanto o modelo que apresentou esta caracteristica foi o ml3.

Ajuste do modelo

Ajustes dos modelos com as funções de Semivariância.

##############
##   WAVE   ##
##############


salvar=variog(INF)
## variog: computing omnidirectional variogram
plot(salvar,ylab=expression("Semivariância ("*Wave*")"),
     xlab="Distancia (m)", main = "Semivariograma")
lines.variomodel(cov.model="wave", cov.pars=c(343145.5, 6.66 ),nug= 0,kappa =.5)

################
##   MATERN   ##
################

salvar=variog(INF)
## variog: computing omnidirectional variogram
plot(salvar,ylab=expression("Semivariância ("*matern*")"),
     xlab="Distancia (m)", main = "Semivariograma")
lines.variomodel(cov.model="matern", cov.pars=c(343145.5 , 2.54 ),nug= 0,
               kappa = 9.86)

Definindo as bordas arbitrƔrias

Bordas do modelo.

points(INF, pt.div="quartiles", xlab="Leste", ylab="Norte")

setwd("F:/Estatistica Espacial")
borda=read.table("bordaINF.txt",h=T)
INF$borders <- with(borda, cbind(x,y))

points(INF, pt.div="quartiles", xlab="leste", ylab="norte")

plot(INF,lowess = T)

Tomando apenas como base o grÔfico acima, pode-se observar que os dados não apresentam normalidade.

Boxcox

Por meio do Boxcox verifica-se se o 1 estÔ contido no intervalo, se caso estiver,conclui-se que os dados nececitam de trasformação.

boxcox(INF,lam=seq(-3,2,1/10))

Interpolação

par(mfrow=c(1,1))
ml3 <- likfit(INF, trend="1st", ini=c(343145.5, 6.66 ),nug= 0)
## ---------------------------------------------------------------
## likfit: likelihood maximisation using the function optim.
## likfit: Use control() to pass additional
##          arguments for the maximisation function.
##         For further details see documentation for optim.
## likfit: It is highly advisable to run this function several
##         times with different initial values for the parameters.
## likfit: WARNING: This step can be time demanding!
## ---------------------------------------------------------------
## likfit: end of numerical maximisation.
ml3
## likfit: estimated model parameters:
##      beta0      beta1      beta2      tausq    sigmasq        phi 
## "1536.547" " -37.656" " -39.559" "   0.000" "1401.524" "   1.705" 
## Practical Range with cor=0.05 for asymptotic range: 5.107397
## 
## likfit: maximised log-likelihood = -139.8
gr=pred_grid(INF$borders,by=0.2)
points(INF)
points(gr,col=2,pch=19,cex=.3)

gr0=gr[.geoR_inout(gr,INF$borders),]
points(gr0,col=3,pch=19,cex=0.3)

Processo de Krigagem

O processo de Krigagem permite construir mapas de incerteza espacial, no qual fornece uma visão global da congruência dos resultados.

kc <- krige.conv(INF, loc=gr, bor=borda, krige=krige.control(obj=ml3))
## krige.conv: results will be returned only for prediction locations inside the borders
## krige.conv: model with mean given by a 1st order polynomial on the coordinates
## krige.conv: Kriging performed using global neighbourhood
names(kc)
## [1] "predict"      "krige.var"    "beta.est"     "distribution"
## [5] "message"      "call"
kc$pred[1:10]
##  [1] 1043.831 1036.046 1028.895 1025.360 1023.141 1020.784 1206.516
##  [8] 1197.951 1050.759 1043.152
image(kc,main="Mapa de Interpolação")

image(kc, main="Mapa de Interpolação",col=gray(seq(1,0.2,len=10)), x.leg=c(-220,-50), y.leg=c(150,180))

kc1 <- krige.conv(INF, loc=gr, bor=borda, krige=krige.control(obj=ml3))
## krige.conv: results will be returned only for prediction locations inside the borders
## krige.conv: model with mean given by a 1st order polynomial on the coordinates
## krige.conv: Kriging performed using global neighbourhood
plot(kc$pred, INF$pred, asp=10)
abline(0,1, col=2)

image(kc1, main="Mapa de Interpolação",col=gray(seq(1,0.2,len=20)), x.leg=c(-220,-50), y.leg=c(150,180))

contour(kc1,main="Mapa de Interpolação",f=T,col= terrain.colors(20), nlev = 20)

numlevel=10
contour(kc1,main="Mapa de Interpolação",c=T,col= terrain.colors(50), nlev = 50)

numlevel=10