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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/permeability_qsar.R
\docType{data}
\name{permeability_qsar}
\alias{permeability_qsar}
\title{Predicting permeability from chemical information}
\source{
Kuhn, Max, and Kjell Johnson. \emph{Applied predictive modeling}. New York:
Springer, 2013.
}
\value{
\item{permeability_qsar}{a data frame}
}
\description{
A quantitative structure-activity relationship (QSAR) data set to predict
when a molecule can permeate cells.
}
\details{
This pharmaceutical data set was used to develop a model for predicting
compounds' permeability. In short, permeability is the measure of a
molecule's ability to cross a membrane. The body, for example, has notable
membranes between the body and brain, known as the blood-brain barrier, and
between the gut and body in the intestines. These membranes help the body
guard critical regions from receiving undesirable or detrimental substances.
For an orally taken drug to be effective in the brain, it first must pass
through the intestinal wall and then must pass through the blood-brain
barrier in order to be present for the desired neurological target.
Therefore, a compound's ability to permeate relevant biological membranes
is critically important to understand early in the drug discovery process.
Compounds that appear to be effective for a particular disease in research
screening experiments, but appear to be poorly permeable may need to be
altered in order improve permeability, and thus the compound's ability to
reach the desired target. Identifying permeability problems can help guide
chemists towards better molecules.
Permeability assays such as PAMPA and Caco-2 have been developed to help
measure compounds' permeability (Kansy et al, 1998). These screens are
effective at quantifying a compound's permeability, but the assay is
expensive labor intensive. Given a sufficient number of compounds that have
been screened, we could develop a predictive model for permeability in an
attempt to potentially reduce the need for the assay. In this project there
were 165 unique compounds; 1107 molecular fingerprints were determined for
each. A molecular fingerprint is a binary sequence of numbers that
represents the presence or absence of a specific molecular sub-structure.
The response is highly skewed, the predictors are sparse (15.5\% are present),
and many predictors are strongly associated.
Columns:
\itemize{
\item \code{permeability}: numeric
\item \code{chem_fp_0001} - \code{chem_fp_1107}: numeric
}
}
\examples{
data(permeability_qsar)
str(permeability_qsar)
}
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