Simulation of Multivariate Linear Model data with response
Simulation of Multivariate Linear Model data with response
bisimrel( n =50, p =100, q = c(10,10,5), rho = c(0.8,0.4), relpos = list(c(1,2), c(2,3)), gamma =0.5, R2 = c(0.8,0.8), ntest =NULL, muY =NULL, muX =NULL, sim =NULL)
Arguments
n: Number of training samples
p: Number of x-variables
q: Vector of number of relevant predictor variables for first, second and common to both responses
rho: A 2-element vector, unconditional and conditional correlation between y_1 and y_2
relpos: A list of position of relevant component for predictor variables. The list contains vectors of position index, one vector or each response
gamma: A declining (decaying) factor of eigen value of predictors (X). Higher the value of gamma, the decrease of eigenvalues will be steeper
R2: Vector of coefficient of determination for each response
ntest: Number of test observation
muY: Vector of average (mean) for each response variable
muX: Vector of average (mean) for each predictor variable
sim: A simrel object for reusing parameters setting
Returns
A simrel object with all the input arguments along with following additional items - X: Simulated predictors
Y: Simulated responses
beta: True regression coefficients
beta0: True regression intercept
relpred: Position of relevant predictors
testX: Test Predictors
testY: Test Response
minerror: Minimum model error
Rotation: Rotation matrix of predictor (R)
type: Type of simrel object, in this case bivariate
lambda: Eigenvalues of predictors
Sigma: Variance-Covariance matrix of response and predictors
Examples
sobj <- bisimrel( n =100, p =10, q = c(5,5,3), rho = c(0.8,0.4), relpos = list(c(1,2,3), c(2,3,4)), gamma =0.7, R2 = c(0.8,0.8))# Regression Coefficients from this simulationsobj$beta
References
Sæbø, S., Almøy, T., & Helland, I. S. (2015). simrel—A versatile tool for linear model data simulation based on the concept of a relevant subspace and relevant predictors. Chemometrics and Intelligent Laboratory Systems, 146, 128-135.
Almøy, T. (1996). A simulation study on comparison of prediction methods when only a few components are relevant. Computational statistics & data analysis, 21(1), 87-107.