\HeaderA{environmental}{Atmospheric environmental conditions in New York City}{environmental}
\keyword{datasets}{environmental}
\begin{Description}\relax
Daily measurements of ozone concentration, wind speed, temperature and
solar radiation in New York City from May to September of 1973.
\end{Description}
\begin{Usage}
\begin{verbatim}environmental\end{verbatim}
\end{Usage}
\begin{Format}\relax
A data frame with 111 observations on the following 4 variables.
\describe{
\item[ozone] Average ozone concentration (of hourly measurements) of
in parts per billion.
\item[radiation] Solar radiation (from 08:00 to 12:00) in langleys.
\item[temperature] Maximum daily emperature in degrees Fahrenheit.
\item[wind] Average wind speed (at 07:00 and 10:00) in miles per hour.
}
\end{Format}
\begin{Author}\relax
Documentation contributed by Kevin Wright.
\end{Author}
\begin{Source}\relax
Bruntz, S. M., W. S. Cleveland, B. Kleiner, and J. L. Warner.  (1974).
The Dependence of Ambient Ozone on Solar Radiation, Wind, Temperature,
and Mixing Height.  In \emph{Symposium on Atmospheric Diffusion and
Air Pollution}, pages 125--128.  American Meterological Society,
Boston.
\end{Source}
\begin{References}\relax
Cleveland, William S. (1993). \emph{Visualizing Data}.  Hobart Press,
Summit, New Jersey.
\end{References}
\begin{Examples}
\begin{ExampleCode}
# Scatter plot matrix with loess lines
splom(~environmental,
  panel=function(x,y){
    panel.xyplot(x,y)
    panel.loess(x,y)
  }
)

# Conditioned plot similar to figure 5.3 from Cleveland
attach(environmental)
Temperature <- equal.count(temperature, 4, 1/2)
Wind <- equal.count(wind, 4, 1/2)
xyplot((ozone^(1/3)) ~ radiation | Temperature * Wind,
  aspect=1,
        prepanel = function(x, y) 
                prepanel.loess(x, y, span = 1),
        panel = function(x, y){
                panel.grid(h = 2, v = 2)
                panel.xyplot(x, y, cex = .5)
                panel.loess(x, y, span = 1)
        },
        xlab = "Solar radiation (langleys)",
        ylab = "Ozone (cube root ppb)")
detach()

# Similar display using the coplot function
with(environmental,{
  coplot((ozone^.33) ~ radiation | temperature * wind,
  number=c(4,4),
  panel = function(x, y, ...) panel.smooth(x, y, span = .8, ...),
  xlab="Solar radiation (langleys)",
  ylab="Ozone (cube root ppb)")
})
\end{ExampleCode}
\end{Examples}

