| Type: | Package | 
| Title: | Iterative Hard Thresholding Extensions to Cyclops | 
| Version: | 1.0.3 | 
| Date: | 2025-7-21 | 
| Maintainer: | Marc A. Suchard <msuchard@ucla.edu> | 
| Description: | Fits large-scale regression models with a penalty that restricts the maximum number of non-zero regression coefficients to a prespecified value. While Chu et al (2020) <doi:10.1093/gigascience/giaa044> describe the basic algorithm, this package uses Cyclops for an efficient implementation. | 
| License: | Apache License 2.0 | 
| Depends: | R (≥ 3.2.2), Cyclops (≥ 1.3.0) | 
| Imports: | ParallelLogger | 
| Suggests: | testthat, knitr, rmarkdown | 
| Encoding: | UTF-8 | 
| RoxygenNote: | 7.3.2 | 
| NeedsCompilation: | no | 
| Packaged: | 2025-07-21 18:55:07 UTC; msuchard | 
| Author: | Marc A. Suchard [aut, cre], Patrick Ryan [aut], Observational Health Data Sciences and Informatics [cph] | 
| Repository: | CRAN | 
| Date/Publication: | 2025-07-21 19:11:35 UTC | 
Create a fastIHT Cyclops prior object
Description
createFastIhtPrior creates a fastIHT Cyclops prior object for use with fitCyclopsModel.
Usage
createFastIhtPrior(
  K,
  penalty = 0,
  exclude = c(),
  forceIntercept = FALSE,
  fitBestSubset = FALSE,
  initialRidgeVariance = 10000,
  tolerance = 1e-08,
  maxIterations = 10000,
  threshold = 1e-06
)
Arguments
K | 
 Maximum # of non-zero covariates  | 
penalty | 
 Specifies the IHT penalty  | 
exclude | 
 A vector of numbers or covariateId names to exclude from prior  | 
forceIntercept | 
 Logical: Force intercept coefficient into regularization  | 
fitBestSubset | 
 Logical: Fit final subset with no regularization  | 
initialRidgeVariance | 
 Numeric: variance used for algorithm initiation  | 
tolerance | 
 Numeric: maximum abs change in coefficient estimates from successive iterations to achieve convergence  | 
maxIterations | 
 Numeric: maximum iterations to achieve convergence  | 
threshold | 
 Numeric: absolute threshold at which to force coefficient to 0  | 
Value
An IHT Cyclops prior object of class inheriting from
"cyclopsPrior" for use with fitCyclopsModel.
Examples
nobs = 500; ncovs = 100
prior <- createFastIhtPrior(K = 3, penalty = log(ncovs), initialRidgeVariance = 1 / log(ncovs))
Create an IHT Cyclops prior object
Description
createIhtPrior creates an IHT Cyclops prior object for use with fitCyclopsModel.
Usage
createIhtPrior(
  K,
  penalty = "bic",
  exclude = c(),
  forceIntercept = FALSE,
  fitBestSubset = FALSE,
  initialRidgeVariance = 0.1,
  tolerance = 1e-08,
  maxIterations = 10000,
  threshold = 1e-06,
  delta = 0
)
Arguments
K | 
 Maximum # of non-zero covariates  | 
penalty | 
 Specifies the IHT penalty; possible values are 'BIC' or 'AIC' or a numeric value  | 
exclude | 
 A vector of numbers or covariateId names to exclude from prior  | 
forceIntercept | 
 Logical: Force intercept coefficient into regularization  | 
fitBestSubset | 
 Logical: Fit final subset with no regularization  | 
initialRidgeVariance | 
 Numeric: variance used for algorithm initiation  | 
tolerance | 
 Numeric: maximum abs change in coefficient estimates from successive iterations to achieve convergence  | 
maxIterations | 
 Numeric: maximum iterations to achieve convergence  | 
threshold | 
 Numeric: absolute threshold at which to force coefficient to 0  | 
delta | 
 Numeric: change from 2 in ridge norm dimension  | 
Value
An IHT Cyclops prior object of class inheriting from
"cyclopsPrior" for use with fitCyclopsModel.
Examples
prior <- createIhtPrior(K = 10)