stdCurve_fitcompare: Compare two fitted standard curves

In shirewoman2/LaurasHelpers: Miscellaneous Helper Functions for Common PK or Analytical Chemistry Tasks

Compare two fitted standard curves

Description

To use this function, use stdCurve to fit the same data.frame two different ways. For example, for one fit, include all data points and for the other, omit troublesome data points to see their effect on the curve. Other examples: Try comparing different weighting schemes or comparing 1st- vs. 2nd-order polynomials. Input to this function is the output from stdCurve from each of the two different ways.

Usage

stdCurve_fitcompare(stdCurve1, stdCurve2, fitNames = NA)

Arguments

stdCurve1	The list output from stdCurve
stdCurve2	The list output from a variation on stdCurve on the same data.frame or on a data.frame with the same columns
fitNames	A preferably succinct character vector with two items describing what the differences are between stdCurve1 and stdCurve2 (optional)

Value

Output is a list of the following named objects:

CurvePlot

A plot of the data and the fitted lines. The two fits will be in different colors.

Data

The input data, including the nominal concentration or mass, columns of the calculated concentration for each of the two fit methods, and columns of the calculated concentration or mass as a percent of nominal concentration or mass for each of the two fits.

Examples

data(ExStdCurve)

# Comparing no weights vs. weighting by 1/x^2
stdCurve1 <- stdCurve(ExStdCurve,
                      normPeak = MET.peakarearatio,
                      nominal = MET.nominalmass,
                      poly = "2nd")

stdCurve2 <- stdCurve(ExStdCurve,
                      normPeak = MET.peakarearatio,
                      nominal = MET.nominalmass,
                      poly = "2nd", weights = "1/x^2")

stdCurve_fitcompare(stdCurve1, stdCurve2)
stdCurve_fitcompare(stdCurve1, stdCurve2, fitNames = c("no weighting", "1/x2 weighting"))


# Comparing all points vs. omitting one point.
stdCurve1 <- stdCurve(ExStdCurve,
                      normPeak = MET.peakarearatio,
                      nominal = MET.nominalmass,
                      poly = "2nd", IDcol = SampleID)

stdCurve2 <- stdCurve(ExStdCurve %>%  dplyr::filter(SampleID != "standard 200"),
                      normPeak = MET.peakarearatio,
                      nominal = MET.nominalmass,
                      poly = "2nd", IDcol = SampleID)

stdCurve_fitcompare(stdCurve1, stdCurve2)
stdCurve_fitcompare(stdCurve1, stdCurve2,
                    fitNames = c("all points", "omit standard 200"))

shirewoman2/LaurasHelpers documentation built on Oct. 22, 2023, 2:07 p.m.