This report was automatically generated with the R package knitr (version 1.5).

library(faraway)
data(globwarm, package = "faraway")
lmod <- lm(nhtemp ~ wusa + jasper + westgreen + chesapeake + tornetrask + urals + 
    mongolia + tasman, globwarm)
sumary(lmod)
            Estimate Std. Error t value Pr(>|t|)
(Intercept) -0.24256    0.02701   -8.98    2e-15
wusa         0.07738    0.04293    1.80  0.07365
jasper      -0.22879    0.07811   -2.93  0.00399
westgreen    0.00958    0.04184    0.23  0.81917
chesapeake  -0.03211    0.03405   -0.94  0.34735
tornetrask   0.09267    0.04505    2.06  0.04161
urals        0.18537    0.09143    2.03  0.04457
mongolia     0.04197    0.04579    0.92  0.36100
tasman       0.11545    0.03011    3.83  0.00019

n = 145, p = 9, Residual SE = 0.18, R-Squared = 0.48
cor(residuals(lmod)[-1], residuals(lmod)[-length(residuals(lmod))])
[1] 0.5833
require(nlme)
Loading required package: nlme
glmod <- gls(nhtemp ~ wusa + jasper + westgreen + chesapeake + tornetrask + 
    urals + mongolia + tasman, correlation = corAR1(form = ~year), data = na.omit(globwarm))
summary(glmod)
Generalized least squares fit by REML
  Model: nhtemp ~ wusa + jasper + westgreen + chesapeake + tornetrask +      urals + mongolia + tasman 
  Data: na.omit(globwarm) 
     AIC    BIC logLik
  -108.2 -76.17   65.1

Correlation Structure: AR(1)
 Formula: ~year 
 Parameter estimate(s):
  Phi 
0.711 

Coefficients:
               Value Std.Error t-value p-value
(Intercept) -0.23011   0.06702  -3.433  0.0008
wusa         0.06674   0.09877   0.676  0.5004
jasper      -0.20244   0.18803  -1.077  0.2835
westgreen   -0.00440   0.08985  -0.049  0.9610
chesapeake  -0.00735   0.07350  -0.100  0.9205
tornetrask   0.03835   0.09483   0.404  0.6865
urals        0.24142   0.22871   1.056  0.2930
mongolia     0.05695   0.10490   0.543  0.5881
tasman       0.12035   0.07457   1.614  0.1089

 Correlation: 
           (Intr) wusa   jasper wstgrn chespk trntrs urals  mongol
wusa       -0.517                                                 
jasper     -0.058 -0.299                                          
westgreen   0.330 -0.533  0.121                                   
chesapeake  0.090 -0.314  0.230  0.147                            
tornetrask -0.430  0.499 -0.197 -0.328 -0.441                     
urals      -0.110 -0.142 -0.265  0.075 -0.064 -0.346              
mongolia    0.459 -0.437 -0.205  0.217  0.449 -0.343 -0.371       
tasman      0.037 -0.322  0.065  0.134  0.116 -0.434  0.416 -0.017

Standardized residuals:
     Min       Q1      Med       Q3      Max 
-2.31123 -0.53484  0.02343  0.50016  2.97225 

Residual standard error: 0.2046 
Degrees of freedom: 145 total; 136 residual
intervals(glmod, which = "var-cov")
Approximate 95% confidence intervals

 Correlation structure:
    lower  est.  upper
Phi  0.51 0.711 0.8384
attr(,"label")
[1] "Correlation structure:"

 Residual standard error:
 lower   est.  upper 
0.1541 0.2046 0.2716 
glmod <- gls(yield ~ variety, oatvar, correlation = corCompSymm(form = ~1 | 
    block))
intervals(glmod)
Approximate 95% confidence intervals

 Coefficients:
              lower  est.    upper
(Intercept) 291.543 334.4 377.2570
variety2     -4.904  42.2  89.3039
variety3    -18.904  28.2  75.3039
variety4    -94.704 -47.6  -0.4961
variety5     57.896 105.0 152.1039
variety6    -50.904  -3.8  43.3039
variety7    -63.104 -16.0  31.1039
variety8      2.696  49.8  96.9039
attr(,"label")
[1] "Coefficients:"

 Correlation structure:
      lower  est.  upper
Rho 0.06596 0.396 0.7494
attr(,"label")
[1] "Correlation structure:"

 Residual standard error:
lower  est. upper 
33.39 47.05 66.28 
data(fpe, package = "faraway")
fpe
                      EI   A   B   C   D  E  F  G  H  J  K  A2  B2  N
Ain                  260  51  64  36  23  9  5  4  4  3  3 105 114 17
Alpes                 75  14  17   9   9  3  1  2  1  1  1  32  31  5
Ariege               107  27  18  13  17  2  2  2  1  1  1  57  33  6
Bouches.du.Rhone    1036 191 204 119 205 29 13 13 10 10  6 466 364 30
Charente.Maritime    367  71  76  47  37  8 34  5  4  4  2 163 142 17
Cotes.du.Nord        396  93  90  57  54 13  5  9  4  3  5 193 155 15
Drome                257  57  55  31  30 10  4  5  4  3  3 116  99 13
Finistere            595 132 149  95  49 21  9 11  6  5 10 249 259 21
Gironde              735 195 137  98  83 20 16 13 13  8  5 356 261 29
Indre                181  34  39  28  28  4  3  4  3  2  1  82  72  8
Landes               219  62  47  31  26  5  3  3  3  2  1 107  84  8
Loire.Atlantique     653 149 156  94  49 23 15 13 10  7  8 274 275 25
Lozere                58  10  18   9   4  2  0  1  1  1  1  20  29  2
Marne                145  32  33  20  15  4  2  3  2  2  1  63  59  8
Morbihan             414  86 117  65  33 14  6  8  5  4  4 162 190 10
Oise                 416  87  88  59  62 13  7 10  6  5  3 192 160 12
Pyrenees.Atlantique  391  90  91  66  33 12  6  6  5  4  3 165 168 17
Rhin                 413  75 125  58  19 17  6  8  6  6  4 138 204 18
Sarthe               346  72  87  49  40 10  6  8  4  3  3 149 145 12
Seine.Maritime       783 171 181  91 123 24 13 18 10  7  6 370 297 23
Sevres               240  54  66  34  16  8  7  5  3  4  2  98 108  7
Val.D.Oise           533 111 100  74  81 22 12 10  7  7  6 252 192 14
Vendee               336  61 105  59  19 10 11  6  5  4  3 115 176  8
Yonne                216  44  52  31  24  7  4  4  3  3  2  91  91  8
lmod <- lm(A2 ~ A + B + C + D + E + F + G + H + J + K + N - 1, fpe, weights = 1/EI)
coef(lmod)
      A       B       C       D       E       F       G       H       J 
 1.0671 -0.1051  0.2460  0.9262  0.2494  0.7551  1.9722 -0.5662  0.6116 
      K       N 
 1.2107  0.5294 
lm(A2 ~ A + B + C + D + E + F + G + H + J + K + N - 1, fpe)$coef
      A       B       C       D       E       F       G       H       J 
 1.0751 -0.1246  0.2574  0.9045  0.6707  0.7825  2.1657 -0.8543  0.1444 
      K       N 
 0.5181  0.5583 
lm(A2 ~ A + B + C + D + E + F + G + H + J + K + N - 1, fpe, weights = 53/EI)$coef
      A       B       C       D       E       F       G       H       J 
 1.0671 -0.1051  0.2460  0.9262  0.2494  0.7551  1.9722 -0.5662  0.6116 
      K       N 
 1.2107  0.5294 
lm(A2 ~ offset(A + G + K) + C + D + E + F + N - 1, fpe, weights = 1/EI)$coef
     C      D      E      F      N 
0.2258 0.9700 0.3902 0.7442 0.6085 
require(mgcv)
Loading required package: mgcv
This is mgcv 1.7-29. For overview type 'help("mgcv-package")'.
M <- list(w = 1/fpe$EI, X = model.matrix(lmod), y = fpe$A2, Ain = rbind(diag(11), 
    -diag(11)), C = matrix(0, 0, 0), array(0, 0), S = list(), off = NULL, p = rep(0.5, 
    11), bin = c(rep(0, 11), rep(-1, 11)))
a <- pcls(M)
names(a) <- colnames(model.matrix(lmod))
round(a, 3)
    A     B     C     D     E     F     G     H     J     K     N 
1.000 0.000 0.208 0.969 0.359 0.743 1.000 0.367 0.000 1.000 0.575 
lmod <- lm(dist ~ speed, cars)
plot(residuals(lmod) ~ speed, cars)

plot of chunk unnamed-chunk-1

wlmod <- gls(dist ~ speed, data = cars, weight = varConstPower(1, form = ~speed))
summary(wlmod)
Generalized least squares fit by REML
  Model: dist ~ speed 
  Data: cars 
    AIC   BIC logLik
  412.8 422.2 -201.4

Variance function:
 Structure: Constant plus power of variance covariate
 Formula: ~speed 
 Parameter estimates:
const power 
3.160 1.022 

Coefficients:
              Value Std.Error t-value p-value
(Intercept) -11.085     4.052  -2.736  0.0087
speed         3.484     0.320  10.880  0.0000

 Correlation: 
      (Intr)
speed -0.9  

Standardized residuals:
    Min      Q1     Med      Q3     Max 
-1.4521 -0.6898 -0.1308  0.6375  3.0757 

Residual standard error: 0.7637 
Degrees of freedom: 50 total; 48 residual
data(corrosion, package = "faraway")
plot(loss ~ Fe, corrosion, xlab = "Iron content", ylab = "Weight loss")
lmod <- lm(loss ~ Fe, corrosion)
sumary(lmod)
            Estimate Std. Error t value Pr(>|t|)
(Intercept)   129.79       1.40    92.5  < 2e-16
Fe            -24.02       1.28   -18.8  1.1e-09

n = 13, p = 2, Residual SE = 3.06, R-Squared = 0.97
abline(coef(lmod))
lmoda <- lm(loss ~ factor(Fe), corrosion)
points(corrosion$Fe, fitted(lmoda), pch = 3)

plot of chunk unnamed-chunk-1

anova(lmod, lmoda)
Analysis of Variance Table

Model 1: loss ~ Fe
Model 2: loss ~ factor(Fe)
  Res.Df   RSS Df Sum of Sq    F Pr(>F)
1     11 102.9                         
2      6  11.8  5      91.1 9.28 0.0086
lmodp <- lm(loss ~ Fe + I(Fe^2) + I(Fe^3) + I(Fe^4) + I(Fe^5) + I(Fe^6), corrosion)
plot(loss ~ Fe, data = corrosion, ylim = c(60, 130))
points(corrosion$Fe, fitted(lmoda), pch = 3)
grid <- seq(0, 2, len = 50)
lines(grid, predict(lmodp, data.frame(Fe = grid)))

plot of chunk unnamed-chunk-1

summary(lmodp)$r.squared
[1] 0.9965
data(gala, package = "faraway")
lsmod <- lm(Species ~ Area + Elevation + Nearest + Scruz + Adjacent, gala)
sumary(lsmod)
            Estimate Std. Error t value Pr(>|t|)
(Intercept)  7.06822   19.15420    0.37   0.7154
Area        -0.02394    0.02242   -1.07   0.2963
Elevation    0.31946    0.05366    5.95  3.8e-06
Nearest      0.00914    1.05414    0.01   0.9932
Scruz       -0.24052    0.21540   -1.12   0.2752
Adjacent    -0.07480    0.01770   -4.23   0.0003

n = 30, p = 6, Residual SE = 60.98, R-Squared = 0.77
require(MASS)
Loading required package: MASS
rlmod <- rlm(Species ~ Area + Elevation + Nearest + Scruz + Adjacent, gala)
summary(rlmod)

Call: rlm(formula = Species ~ Area + Elevation + Nearest + Scruz + 
    Adjacent, data = gala)
Residuals:
   Min     1Q Median     3Q    Max 
-74.39 -18.35  -6.36  21.19 229.08 

Coefficients:
            Value  Std. Error t value
(Intercept)  6.361 12.390      0.513 
Area        -0.006  0.015     -0.421 
Elevation    0.248  0.035      7.132 
Nearest      0.359  0.682      0.527 
Scruz       -0.195  0.139     -1.401 
Adjacent    -0.055  0.011     -4.765 

Residual standard error: 29.7 on 24 degrees of freedom
wts <- rlmod$w
names(wts) <- row.names(gala)
head(sort(wts), 10)
   SantaCruz   SantaMaria SanCristobal        Pinta     Gardner1 
      0.1746       0.3078       0.4142       0.5376       0.6613 
    Espanola     Gardner2       Baltra    Bartolome     Caldwell 
      0.6795       0.8500       1.0000       1.0000       1.0000 
require(quantreg)
Loading required package: quantreg
Loading required package: SparseM

Attaching package: 'SparseM'

The following object is masked from 'package:base':

    backsolve
l1mod <- rq(Species ~ Area + Elevation + Nearest + Scruz + Adjacent, data = gala)
summary(l1mod)

Call: rq(formula = Species ~ Area + Elevation + Nearest + Scruz + Adjacent, 
    data = gala)

tau: [1] 0.5

Coefficients:
            coefficients lower bd  upper bd 
(Intercept)   1.31445    -19.87777  24.37411
Area         -0.00306     -0.03185   0.52800
Elevation     0.23211      0.12453   0.50196
Nearest       0.16366     -3.16339   2.98896
Scruz        -0.12314     -0.47987   0.13476
Adjacent     -0.05185     -0.10458   0.01739
set.seed(123)
ltsmod <- ltsreg(Species ~ Area + Elevation + Nearest + Scruz + Adjacent, gala)
coef(ltsmod)
(Intercept)        Area   Elevation     Nearest       Scruz    Adjacent 
   12.50668     1.54536     0.01673     0.52349    -0.09407    -0.14259 
ltsmod <- ltsreg(Species ~ Area + Elevation + Nearest + Scruz + Adjacent, gala, 
    nsamp = "exact")
coef(ltsmod)
(Intercept)        Area   Elevation     Nearest       Scruz    Adjacent 
    9.38115     1.54366     0.02412     0.81111    -0.11773    -0.19792 
bcoef <- matrix(0, 1000, 6)
for (i in 1:1000) {
    newy <- predict(ltsmod) + residuals(ltsmod)[sample(30, rep = T)]
    brg <- ltsreg(newy ~ Area + Elevation + Nearest + Scruz + Adjacent, gala, 
        nsamp = "best")
    bcoef[i, ] <- brg$coef
}
colnames(bcoef) <- names(coef(ltsmod))
apply(bcoef, 2, function(x) quantile(x, c(0.025, 0.975)))
      (Intercept)  Area Elevation Nearest    Scruz Adjacent
2.5%        1.918 1.494  -0.01462  0.1588 -0.26238  -0.2203
97.5%      21.467 1.607   0.07333  1.9147  0.09822  -0.1270
require(ggplot2)
bcoef <- data.frame(bcoef)
p1 <- ggplot(bcoef, aes(x = Area)) + geom_density() + xlim(1.45, 1.65)
p1 + geom_vline(xintercept = c(1.4976, 1.623), linetype = "dashed")
Warning: Removed 25 rows containing non-finite values (stat_density).

plot of chunk unnamed-chunk-1

p2 <- ggplot(bcoef, aes(x = Adjacent)) + geom_density() + xlim(-0.25, -0.13)
p2 + geom_vline(xintercept = c(-0.23375, -0.15138), linetype = "dashed")
Warning: Removed 39 rows containing non-finite values (stat_density).

plot of chunk unnamed-chunk-1

limod <- lm(Species ~ Area + Elevation + Nearest + Scruz + Adjacent, gala, subset = (row.names(gala) != 
    "Isabela"))
sumary(limod)
            Estimate Std. Error t value Pr(>|t|)
(Intercept)  22.5861    13.4019    1.69   0.1055
Area          0.2957     0.0619    4.78  8.0e-05
Elevation     0.1404     0.0497    2.82   0.0096
Nearest      -0.2552     0.7217   -0.35   0.7269
Scruz        -0.0901     0.1498   -0.60   0.5534
Adjacent     -0.0650     0.0122   -5.32  2.1e-05

n = 29, p = 6, Residual SE = 41.65, R-Squared = 0.87
data(star, package = "faraway")
plot(light ~ temp, star)
gs1 <- lm(light ~ temp, star)
abline(coef(gs1))
gs2 <- rlm(light ~ temp, star)
abline(coef(gs2), lty = 2)
gs3 <- ltsreg(light ~ temp, star, nsamp = "exact")
abline(coef(gs3), lty = 5)

plot of chunk unnamed-chunk-1

i <- order(pipeline$Field)
npipe <- pipeline[i, ]
ff <- gl(12, 9)[-108]
meanfield <- unlist(lapply(split(npipe$Field, ff), mean))
varlab <- unlist(lapply(split(npipe$Lab, ff), var))

The R session information (including the OS info, R version and all packages used):

sessionInfo()
R version 3.1.0 (2014-04-10)
Platform: x86_64-apple-darwin13.1.0 (64-bit)

locale:
[1] en_GB.UTF-8/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8

attached base packages:
[1] graphics  grDevices utils     datasets  methods   stats     base     

other attached packages:
[1] quantreg_5.05   SparseM_1.03    MASS_7.3-31     mgcv_1.7-29    
[5] nlme_3.1-117    faraway_1.0.6   knitr_1.5       ggplot2_0.9.3.1

loaded via a namespace (and not attached):
 [1] colorspace_1.2-4   dichromat_2.0-0    digest_0.6.4      
 [4] evaluate_0.5.3     formatR_0.10       grid_3.1.0        
 [7] gtable_0.1.2       labeling_0.2       lattice_0.20-29   
[10] Matrix_1.1-3       munsell_0.4.2      plyr_1.8.1        
[13] proto_0.3-10       RColorBrewer_1.0-5 Rcpp_0.11.1       
[16] reshape2_1.2.2     scales_0.2.3       stringr_0.6.2     
[19] tools_3.1.0       
Sys.time()
[1] "2014-06-16 14:02:09 BST"