\name{ozone}
\alias{ozone}
\title{
  Data set of ozone measurements at 20 Chicago monitoring stations. 
}
\description{
The \code{ozone} data is a list of 
components, x and y.  x 
component is longitude and latitude position of each of the 20 
Chicago monitoring stations, y is the average 
daily ozone values over the time period 6/3/87-8/30/87 and lon.lat is 
the longitude-latitude locations of the data.
}
\usage{
data(ozone)
}
\format{
This data set is a list containing the following components: 
}
\describe{
\item{x}{
Longitude-latitude postion of monitoring stations. 
}
\item{y}{
Average daily ozone values over 1987 summer. 
}
}
\source{
AIRS, the EPA air quality data base. 
}
\seealso{
Tps, Krig  
}
\examples{
fit<- Tps(ozone$x, ozone$y) 
# fitting a surface to ozone measurements. 
surface( fit, type="I")
}
\keyword{datasets}
% docclass is function
% Converted by Sd2Rd version 1.21.