case2202: Characteristics Associated with Salamander Habitat

In Sleuth2: Data Sets from Ramsey and Schafer's "Statistical Sleuth (2nd Ed)"

Description

The Del Norte Salamander (plethodon elongates) is a small (5–7 cm) salamander found among rock rubble, rock outcrops and moss-covered talus in a narrow range of northwest California. To study the habitat characteristics of the species and particularly the tendency of these salamanders to reside in dwindling old-growth forests, researchers selected 47 sites from plausible salamander habitat in national forest and parkland. Randomly chosen grid points were searched for the presence of a site with suitable rocky habitat. At each suitable site, a 7 metre by 7 metre search are was examined for the number of salamanders it contained. This data frame contains the counts of salamanders at the sites, along with the percentage of forest canopy and age of the forest in years.

Usage

case2202

Format

A data frame with 47 observations on the following 4 variables.

Site

Investigated site

Salaman

Number of salamanders found in 49 m$^2$ area

PctCover

Percentage of canopy cover

Forestage

Forest age

Source

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

References

Welsh, H.H. and Lind, A.J. (1995). Journal of Herpetology 29(2): 198–210.

Examples

str(case2202)

Example output

'data.frame':	47 obs. of  4 variables:
 $ Site     : num  1 2 3 4 5 6 7 8 9 10 ...
 $ Salaman  : num  13 11 11 9 8 7 6 6 5 5 ...
 $ PctCover : num  85 86 90 88 89 83 83 91 88 90 ...
 $ Forestage: num  316 88 548 64 43 368 200 71 42 551 ...

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