Leaf and Air Temperature Data

Description

These data consist of measurements of vapour pressure and of the difference between leaf and air temperature.

Usage

leaftemp

Format

This data frame contains the following columns:

CO2level

Carbon Dioxide level low, medium, high

vapPress

Vapour pressure

tempDiff

Difference between leaf and air temperature

BtempDiff

a numeric vector

Source

Katharina Siebke and Susan von Cammerer, Australian National University.

Examples

print("Fitting Multiple Lines - Example 7.3")

leaf.lm1 <- lm(tempDiff ~ 1 , data = leaftemp)
leaf.lm2 <- lm(tempDiff ~ vapPress, data = leaftemp)
leaf.lm3 <- lm(tempDiff ~ CO2level + vapPress, data = leaftemp)
leaf.lm4 <- lm(tempDiff ~ CO2level + vapPress + vapPress:CO2level,
  data = leaftemp)

anova(leaf.lm1, leaf.lm2, leaf.lm3, leaf.lm4)

summary(leaf.lm2)
plot(leaf.lm2)

Results

R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

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'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
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> library(DAAG)
Loading required package: lattice
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/DAAG/leaftemp.Rd_%03d_medium.png", width=480, height=480)
> ### Name: leaftemp
> ### Title: Leaf and Air Temperature Data
> ### Aliases: leaftemp
> ### Keywords: datasets
> 
> ### ** Examples
> 
> print("Fitting Multiple Lines - Example 7.3")
[1] "Fitting Multiple Lines - Example 7.3"
> 
> leaf.lm1 <- lm(tempDiff ~ 1 , data = leaftemp)
> leaf.lm2 <- lm(tempDiff ~ vapPress, data = leaftemp)
> leaf.lm3 <- lm(tempDiff ~ CO2level + vapPress, data = leaftemp)
> leaf.lm4 <- lm(tempDiff ~ CO2level + vapPress + vapPress:CO2level,
+   data = leaftemp)
> 
> anova(leaf.lm1, leaf.lm2, leaf.lm3, leaf.lm4)
Analysis of Variance Table

Model 1: tempDiff ~ 1
Model 2: tempDiff ~ vapPress
Model 3: tempDiff ~ CO2level + vapPress
Model 4: tempDiff ~ CO2level + vapPress + vapPress:CO2level
  Res.Df    RSS Df Sum of Sq       F   Pr(>F)   
1     61 39.999                                 
2     60 34.727  1    5.2720 11.3305 0.001383 **
3     58 28.183  2    6.5441  7.0322 0.001885 **
4     56 26.056  2    2.1262  2.2848 0.111205   
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
> 
> summary(leaf.lm2)

Call:
lm(formula = tempDiff ~ vapPress, data = leaftemp)

Residuals:
     Min       1Q   Median       3Q      Max 
-1.36804 -0.61190  0.08227  0.50402  1.77327 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)   3.0970     0.5836   5.307  1.7e-06 ***
vapPress     -0.8566     0.2838  -3.018  0.00373 ** 
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Residual standard error: 0.7608 on 60 degrees of freedom
Multiple R-squared:  0.1318,	Adjusted R-squared:  0.1173 
F-statistic: 9.109 on 1 and 60 DF,  p-value: 0.00373

> plot(leaf.lm2)
> 
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>