dewpoint                package:DAAG                R Documentation

_D_e_w_p_o_i_n_t _D_a_t_a

_D_e_s_c_r_i_p_t_i_o_n:

     The 'dewpoint' data frame has 72 rows and 3 columns. Monthly data
     were obtained for a number of sites (in Australia) and a number of
     months.

_U_s_a_g_e:

     dewpoint

_F_o_r_m_a_t:

     This data frame contains the following columns:

     _m_a_x_t_e_m_p monthly minimum temperatures

     _m_i_n_t_e_m_p monthly maximum temperatures

     _d_e_w_p_t monthly average dewpoint for each combination of minimum and
          maximum temperature readings (formerly dewpoint)

_S_o_u_r_c_e:

     Dr Edward Linacre, visiting fellow in the Australian National
     University Department of Geography.

_E_x_a_m_p_l_e_s:

     print("Additive Model - Example 7.5")
     require(splines)
     attach(dewpoint)   
     ds.lm <- lm(dewpt ~ bs(maxtemp,5) + bs(mintemp,5), data=dewpoint)
     ds.fit <-predict(ds.lm, type="terms", se=TRUE)
     oldpar <- par(mfrow=c(1,2))
     plot(maxtemp, ds.fit$fit[,1], xlab="Maximum temperature",
          ylab="Change from dewpoint mean",type="n")
     lines(maxtemp,ds.fit$fit[,1])
     lines(maxtemp,ds.fit$fit[,1]-2*ds.fit$se[,1],lty=2)
     lines(maxtemp,ds.fit$fit[,1]+2*ds.fit$se[,1],lty=2)
     plot(mintemp,ds.fit$fit[,2],xlab="Minimum temperature",
          ylab="Change from dewpoint mean",type="n")
     ord<-order(mintemp)
     lines(mintemp[ord],ds.fit$fit[ord,2])
     lines(mintemp[ord],ds.fit$fit[ord,2]-2*ds.fit$se[ord,2],lty=2)
     lines(mintemp[ord],ds.fit$fit[ord,2]+2*ds.fit$se[ord,2],lty=2)
     detach(dewpoint)
     par(oldpar)

