［R］例2.2 風速と直流発電量（「線形回帰分析」（朝倉書店）pp.62-67）その1

p.63に掲載されている3つのモデルについて、それぞれlm関数を使って計算している。表2.1（p.62）の値をCSV形式で入力したtable2_1.csvをカレントディレクトリに置いておくこと。

> dtf <- read.csv("table2_1.csv", header = TRUE)
> xxi <- as.double(dtf$WV)
> yyi <- as.double(dtf$DC)
> # 式(2.28)
> r1 <- lm(yyi ~ 1 + xxi)
> print(summary(r1))
Call:
lm(formula = yyi ~ 1 + xxi)
Residuals:
     Min       1Q   Median       3Q      Max 
-0.59869 -0.14099  0.06059  0.17262  0.32184 
Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)  0.13088    0.12599   1.039     0.31    
xxi          0.24115    0.01905  12.659 7.55e-12 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 0.2361 on 23 degrees of freedom
Multiple R-squared:  0.8745,    Adjusted R-squared:  0.869 
F-statistic: 160.3 on 1 and 23 DF,  p-value: 7.546e-12
> # 式(2.29)
> r2 <- lm(yyi ~ 1 + log(xxi))
> print(summary(r2))
Call:
lm(formula = yyi ~ 1 + log(xxi))
Residuals:
     Min       1Q   Median       3Q      Max 
-0.31619 -0.07685  0.02395  0.11139  0.23029 
Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept) -0.83036    0.11083  -7.493  1.3e-07 ***
log(xxi)     1.41677    0.06234  22.728  < 2e-16 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 0.1376 on 23 degrees of freedom
Multiple R-squared:  0.9574,    Adjusted R-squared:  0.9555 
F-statistic: 516.6 on 1 and 23 DF,  p-value: < 2.2e-16
> # 式(2.30)
> r3 <- lm(yyi ~ 1 + I(1 / xxi))
> print(summary(r3))
Call:
lm(formula = yyi ~ 1 + I(1/xxi))
Residuals:
     Min       1Q   Median       3Q      Max 
-0.20547 -0.04940  0.01100  0.08352  0.12204 
Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)   2.9789     0.0449   66.34   <2e-16 ***
I(1/xxi)     -6.9345     0.2064  -33.59   <2e-16 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 0.09417 on 23 degrees of freedom
Multiple R-squared:   0.98,     Adjusted R-squared:  0.9792 
F-statistic:  1128 on 1 and 23 DF,  p-value: < 2.2e-16