findFClog             package:factDesign             R Documentation

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

     'findFClog' contructs a point estimate of fold change using the
     linear model coefficients in an lm object for data that has been
     log-transformed.

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

     findFClog(model, lambdaNum, lambdaDenom)

_A_r_g_u_m_e_n_t_s:

   model: An lm object.

lambdaNum: A numeric vector of coefficients for the parameters to be
          used in the numerator of the fold change estimate. 

lambdaDenom: A numeric vector of coefficients for the parameters to be
          used in the denominator of the fold change estimate.

_V_a_l_u_e:

     A point estimate of the fold change between the experimental
     conditions specified in the lambdaNum and lambdaDenom vectors for
     data that has been log-transformed for the linear model
     estimation.

_A_u_t_h_o_r(_s):

     Denise Scholtens

_S_e_e _A_l_s_o:

     'par2lambda', 'findFC'

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

     data(estrogen)
     ES <- pData(estrogen)[["ES"]]
     TIME <- pData(estrogen)[["TIME"]]
     fit <- lm(log(exprs(estrogen)[6,]) ~ ES + TIME + ES*TIME)
     betaNames <- names(fit[["coef"]])
     betas <- list(c("(Intercept)","ESP","TIME48h","ESP:TIME48h"),
                                             c("(Intercept)","ESP"))
     coefs <- list(c(1,1),c(1,1))
     lambda <- par2lambda(betaNames,betas,coefs)
     findFClog(fit,lambda[1,],lambda[2,])

