# case1002: The Energy Costs of Echolocation by Bats In Sleuth2: Data Sets from Ramsey and Schafer's "Statistical Sleuth (2nd Ed)"

## Description

The data are on in–flight energy expenditure and body mass from 20 energy studies on three types of flying vertebrates: echolocating bats, non–echolocating bats and non–echolocating birds.

## Usage

 `1` ```case1002 ```

## Format

A data frame with 20 observations on the following 4 variables.

`Species`

species

`Mass`

mass (in grams)

`Type`

a factor with 3 levels indicating the type of flying vertebrate

`Energy`

in–flight energy expenditure (in W)

## Source

Ramsey, F.L. and Schafer, D.W. (2002). The Statistical Sleuth: A Course in Methods of Data Analysis (2nd ed), Duxbury.

## References

Speakman, J.R. and Racey, P.A. (1991). No cost of Echolocation for Bats in Flight, Nature 350: 421–423.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22``` ```str(case1002) plot(log(Energy)~log(Mass), case1002, pch = ifelse(Type=="echolocating bats", 19, ifelse(Type=="non-echolocating birds", 21, 24))) plot(Energy~Mass, case1002, log="xy", xlab = "Body Mass (g) (log scale)", ylab = "Energy Expenditure (W) (log scale)", pch = ifelse(Type=="echolocating bats", 19, ifelse(Type=="non-echolocating birds", 21, 24))) legend(7, 50, pch=c(24, 21, 19), c("Non-echolocating bats", "Non-echolocating birds","Echolocating bats")) library(lattice) yticks <- c(1,2,5,10,20,50) xticks <- c(10,20,50,100,200,500) xyplot(Energy ~ Mass, case1002, groups=Type, scales = list(log=TRUE, y=list(at=yticks), x=list(at=xticks)), ylab = "Energy Expenditure (W) (log scale)", xlab = "Body Mass (g) (log scale)", auto.key = list(x = 0.2, y = 0.9, corner = c(0, 1), border = TRUE)) ```

### Example output

```'data.frame':	20 obs. of  4 variables:
\$ Species: chr  "Pteropus gouldii" "Pteropus poliocephalus" "Hypsignathus monstrosus" "Eidolon helvum" ...
\$ Mass   : num  779 628 258 315 24.3 ...
\$ Type   : Factor w/ 3 levels "non-echolocating bats",..: 1 1 1 1 2 2 2 2 2 2 ...
\$ Energy : num  43.7 34.8 23.3 22.4 2.46 ...
```

Sleuth2 documentation built on May 2, 2019, 7:01 a.m.