data {pqrBayes}R Documentation

simulated data for demonstrating the features of pqrBayes

Description

Simulated gene expression data for demonstrating the features of pqrBayes.

Format

The data object consists of five components: g, y, u, e and coeff. coeff contains the true values of parameters used for generating the response variable yy.

Details

The model for generating Y

Use subscript ii to denote the iith subject. Let (Xi,Yi,Vi,Ei)(\boldsymbol X_{i}, Y_{i}, V_{i}, \boldsymbol E_{i}), (i=1,,ni=1,\ldots,n) be independent and identically distributed random vectors. YiY_{i} is a continuous response variable representing the disease phenotype. Xi=(Xi0,...,Xip)\boldsymbol X_{i}=(X_{i0},...,X_{ip})^\top denotes a (1+p)(1+p)–dimensional vector of predictors (e.g. genetic factors) with the first element Xi0=1X_{i0}=1. The environmental factor ViI ⁣R1V_i \in \rm I\!R^1 is a univariate index variable. Ei=(Ei1,...,Eiq)\boldsymbol E_{i}=(E_{i1},...,E_{iq})^\top is the qq-dimensional vector of clinical covariates. At a given quantile level τ\tau, considering the following quantile varying coefficient model:

Yi=k=1qEikβk,τ+j=0pγj,τ(Vi)Xij+ϵi,τ,Y_{i}=\sum_{k=1}^{q} E_{ik} \beta_{k,\tau} +\sum_{j=0}^{p}\gamma_{j,\tau}(V_i)X_{ij} +\epsilon_{i,\tau},

where βk,τ\beta_{k,\tau}'s are the regression coefficients for the clinical covariates and γj,τ()\gamma_{j,\tau}(\cdot)'s are unknown smooth varying-coefficient functions. The regression coefficients of X\boldsymbol X vary with the univariate index variable v=(v1,...,vn)\boldsymbol v=(v_1,...,v_n)^\top. The ϵi,τ\epsilon_{i,\tau} is the random error. For simplicity of notation, the quantile level τ\tau has been suppressed hereafter.

The true model that we used to generate Y:

Yi=γ0(vi)+γ1(vi)Xi1+γ2(vi)Xi2+γ3(vi)Xi3+ϵi,Y_i=\gamma_0(v_i)+\gamma_1(v_i)X_{i1}+\gamma_2(v_i)X_{i2}+\gamma_3(v_i)X_{i3}+\epsilon_i,

where ϵiN(0,1)\epsilon_i\sim N(0,1), γ0=1.5sin(0.2πvi\gamma_{0}=1.5\sin(0.2\pi*v_i), γ1=2exp(0.2vi1)1.5\gamma_{1}=2\exp(0.2v_i-1)-1.5 , γ2=22vi\gamma_{2}=2-2v_i and γ3=4+(vi2)3/6\gamma_3=-4+(v_i-2)^3/6.

See Also

pqrBayes

Examples

data(data)
g=data$g
dim(g)
coeff=data$coeff
print(coeff)



[Package pqrBayes version 1.0.2 Index]