Get the Slope of regression log(y) ~ x

It calculates the slope with linear regression of log(y) ~ x

Usage

Slope(x, y)

Arguments

x: vector values of the independent variable, usually time
y: vector values of the dependent variable, usually concentration

Details

With time-concentration curve, you frequently need to estimate slope in log(concentration) ~ time. This function is usually called by BestSlope function, and you seldom need to call this function directly.

Value

R2: R-squared
R2ADJ: adjusted R-squared
LAMZNPT: number of points used for slope
LAMZ: negative of the slope, lambda_z
b0: intercept of the regression line
CORRXY: correlation of log(y) and x
LAMZLL: earliest x for lambda_z
LAMZUL: last x for lambda_z

Author

Kyun-Seop Bae <[email protected]>

Examples

Slope(Indometh[Indometh$Subject==1, "time"], Indometh[Indometh$Subject==1, "conc"])
#>         R2      R2ADJ    LAMZNPT       LAMZ         b0     CORRXY     LAMZLL 
#>  0.5340746  0.4823051 11.0000000  0.1332090  0.8108532 -0.7308041  0.2500000 
#>     LAMZUL 
#>  8.0000000