data {roben} | R Documentation |
simulated data for demonstrating the features of roben
Description
Simulated gene expression data for demonstrating the features of roben.
Usage
data("GxE_small")
data("GxE_large")
Format
GxE_small consists of five components: X, Y, E, clin and coeff. coeff contains the true values of parameters used for generating Y.
GxE_large contains larger datasets: X2, Y2, E2 and clin2
Details
The data model for generating Y
Use subscript i
to denote the i
th subject. Let (X_{i}, Y_{i}, E_{i}, Clin_{i})
, (i=1,\ldots,n
) be
independent and identically distributed random vectors. Y_{i}
is a continuous response variable representing the
disease phenotype. X_{i}
is the p
–dimensional vector of G factors. The environmental factors and clinical covariates
are denoted as the k
-dimensional vector E_{i}
and the q
-dimensional vector Clin_{i}
, respectively.
The \epsilon
follows some heavy-tailed distribution.
Considering the following model:
Y_{i} = \alpha_{0} + \sum_{t=1}^{q}\alpha_{t}Clin_{it} + \sum_{m=1}^{k}\theta_{m}E_{im} + \sum_{j=1}^{p}\gamma_{j}X_{ij} + \sum_{j=1}^{p}\sum_{m=1}^{k}\zeta_{jm}E_{im}X_{ij} +\epsilon_{i},
where \alpha_{0}
is the intercept; \alpha_{t}
's, \theta_{m}
's, \gamma_{j}
's and \zeta_{jm}
's are
the regression coefficients for the clinical covariates, environmental factors, genetic factors and G\times
E interactions, respectively.
Define \beta_{j}=(\gamma_{j}, \zeta_{j1},\ldots,\zeta_{jk})^\top \equiv (\beta_{j1},\ldots,\beta_{jL})^\top
and
U_{ij}=(X_{ij},X_{ij}E_{i1}\ldots,X_{ij}E_{ik})^\top \equiv (U_{ij1},\dots,U_{ijL})^\top
, where L=k+1
.
The model can be written as
Y_{i} = \alpha_{0} + \sum_{t=1}^{q}\alpha_{t}Clin_{it} + \sum_{m=1}^{k}\theta_{m}E_{im} + \sum_{j=1}^{p} \big(U_{ij}^\top\beta_{j}\big) +\epsilon_{i},
where the coefficient vector \beta_{j}
represents all the main and interaction effects corresponding to the j
th genetic measurement.
The object coeff in GxE_small is a list of four components, corresponding to \alpha_{0}
, \alpha_{t}
's, \theta_{m}
's and \beta_{j}
's.
See Also
Examples
data(GxE_small)
dim(X)
print(coeff)
data(GxE_large)
dim(X)
print(coeff)