urine {cond}

Urine Data

Description

The urine data frame has 77 rows and 7 columns.

79 urine specimens were analyzed in an effort to determine if certain physical characteristics of the urine might be related to the formation of calcium oxalate crystals.

Usage

data(urine)

Format

This data frame contains the following columns:

r

indicator of the presence of calcium oxalate crystals;

gravity

the specific gravity of the urine, i.e. the density of urine relative to water;

ph

the pH reading of the urine;

osmo

the osmolarity of the urine. Osmolarity is proportional to the concentration of molecules in solution (mOsm).

conduct

The conductivity of the urine. Conductivity is proportional to the concentration of charged ions in solution (mMho milliMho).

urea

the urea concentration in millimoles per litre;

calc

the calcium concentration in millimoles per litre.

Source

The data were obtained from

Andrews, D. F. and Herzberg, A. M. (1985) Data: A Collection of Problems from Many Fields for the Student and Research Worker, Cambridge: Cambridge University Press.

References

Davison, A. C. and Hinkley, D. V. (1997). Bootstrap Methods and Their Application (Example 7.8). Cambridge: Cambridge University Press.

Examples

data(urine)
summary(urine)
pairs(urine)
##
data(urine)
urine.glm <- glm(r ~ gravity + ph + osmo + conduct + urea + log(calc), 
                 family = binomial, data = urine)
labels(coef(urine.glm))
urine.cond <- cond(urine.glm, log(calc))
##
## (large estimate of regression coefficient)
urine.glm <- glm(r ~ gravity + ph + osmo + conduct + urea + calc, 
                 family = binomial, data = urine)
coef(urine.glm)
urine.glm <- glm(r ~ I(gravity * 100) + ph + osmo + conduct + urea + calc, 
                 family = binomial, data = urine)
coef(urine.glm)
urine.cond <- cond(urine.glm, I(gravity * 100))