refund (version 0.1-37)

vb_mult_fpca: Multilevel FoSR using Variational Bayes and FPCA

Description

Fitting function for function-on-scalar regression for multilevel data. This function estimates model parameters using a VB and estimates the residual covariance surface using FPCA.

Usage

vb_mult_fpca(
  formula,
  data = NULL,
  verbose = TRUE,
  Kt = 5,
  Kp = 2,
  alpha = 0.1,
  argvals = NULL
)

Arguments

formula

a formula indicating the structure of the proposed model.

data

an optional data frame, list or environment containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which the function is called.

verbose

logical defaulting to TRUE -- should updates on progress be printed?

Kt

number of spline basis functions used to estimate coefficient functions

Kp

number of FPCA basis functions to be estimated

alpha

tuning parameter balancing second-derivative penalty and zeroth-derivative penalty (alpha = 0 is all second-derivative penalty)

argvals

not currently implemented

Author

Jeff Goldsmith

References

Goldsmith, J., Kitago, T. (2016). Assessing Systematic Effects of Stroke on Motor Control using Hierarchical Function-on-Scalar Regression. Journal of the Royal Statistical Society: Series C, 65 215-236.