> 
> pdf("E:\\sta4210\\CH03TA07.pdf")
> 
> plot(X,Y)
> 
> saletrn.reg1 <- lm(Y~X)
> summary(saletrn.reg1)

Call:
lm(formula = Y ~ X)

Residuals:
     Min       1Q   Median       3Q      Max 
-12.0700  -2.2262  -0.3925   4.3187  11.0000 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)   34.945      5.948   5.875 0.000372 ***
X             35.770      3.587   9.973 8.66e-06 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

Residual standard error: 8.02 on 8 degrees of freedom
Multiple R-squared: 0.9256,     Adjusted R-squared: 0.9163 
F-statistic: 99.46 on 1 and 8 DF,  p-value: 8.66e-06 

> plot(saletrn.reg1)
> 
> 
> dev.off()
null device 
          1 
> saletrn <- read.table("E:\\sta4210\\CH03TA07.txt",header=F,col.names=c("X","Y"))
> 
> attach(saletrn)
The following object(s) are masked from 'saletrn (position 3)':

    X, Y
The following object(s) are masked from 'toluca (position 4)':

    X, Y
The following object(s) are masked from 'toluca (position 5)':

    X, Y
> 
> pdf("E:\\sta4210\\CH03TA07.pdf")
> 
> plot(X,Y)
> 
> saletrn.reg1 <- lm(Y~X)
> summary(saletrn.reg1)

Call:
lm(formula = Y ~ X)

Residuals:
     Min       1Q   Median       3Q      Max 
-12.0700  -2.2262  -0.3925   4.3187  11.0000 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)   34.945      5.948   5.875 0.000372 ***
X             35.770      3.587   9.973 8.66e-06 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

Residual standard error: 8.02 on 8 degrees of freedom
Multiple R-squared: 0.9256,     Adjusted R-squared: 0.9163 
F-statistic: 99.46 on 1 and 8 DF,  p-value: 8.66e-06 

> plot(saletrn.reg1)
> 
> sqrtX <- sqrt(X)
> 
> plot(sqrtX,Y)
> 
> saletrn.reg2 <- lm(Y~sqrtX)
> summary(saletrn.reg2)

Call:
lm(formula = Y ~ sqrtX)

Residuals:
    Min      1Q  Median      3Q     Max 
-9.3221 -4.1884 -0.2367  4.1007  7.7200 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)  -10.328      7.892  -1.309    0.227    
sqrtX         83.453      6.444  12.951  1.2e-06 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

Residual standard error: 6.272 on 8 degrees of freedom
Multiple R-squared: 0.9545,     Adjusted R-squared: 0.9488 
F-statistic: 167.7 on 1 and 8 DF,  p-value: 1.197e-06 

> plot(saletrn.reg2)
> 
> 
> 
> dev.off()