prater                package:betareg                R Documentation

_P_r_a_t_e_r'_s _g_a_s_o_l_i_n_e _d_a_t_a

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

     Operational data of the proportion of crude oil converted to
     gasoline after distilation and fractionation.

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

     data(prater)

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

     A data frame with 32 observations on 5 variables.

     [,1] 'oil'        The proportion of crude oil converted to
     gasoline after distilation and fractionation. [,2] 'apigrav'   
     The crude oil gravity (degrees API). [,3] 'vaporpress' The vapor
     pressure of the crude oil (lbf/in2 ). [,4] 'tempten'    The crude
     oil 10 [,5] 'temp'       The temperature (degrees F) at which all
     the gasoline is vaporized.

_D_e_t_a_i_l_s:

     This dataset was collected by Prater (1956), its dependent
     variable is the proportion of crude oil after distilation and
     fractionation. This dataset was analyzed by Atkunson (1985), who
     used the linear regression model and noted that there is
     ``indication that the error distribution is not quite symmetrical,
     giving rise to some unduly large and small residuals'' (p. 60).

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

     Prater, N.H. (1956). Estimate gasoline yields from crudes. New
     York: Springer-Verlag.

_R_e_f_e_r_e_n_c_e_s:

     Atkinson, A.C. (1985). _Plots, Transformations and Regression: An
     Introduction to Graphical Methods of Diagnostic Regression
     Analysis._ New York: Oxford University Press.

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

     data(prater)
     fit <- betareg(oil ~ apigrav + vaporpress + tempten + temp, data=prater)
     plot(fit)

