- X
An object of class FBM.
- y01.train
Vector of responses, corresponding to ind.train
.
Must be only 0s and 1s.
- ind.train
An optional vector of the row indices that are used,
for the training part. If not specified, all rows are used.
Don't use negative indices.
- ind.col
An optional vector of the column indices that are used.
If not specified, all columns are used. Don't use negative indices.
- covar.train
Matrix of covariables to be added in each model to correct
for confounders (e.g. the scores of PCA), corresponding to ind.train
.
Default is NULL
and corresponds to only adding an intercept to each model.
You can use covar_from_df()
to convert from a data frame.
- base.train
Vector of base predictions. Model will be learned starting
from these predictions. This can be useful if you want to previously fit
a model with large-effect variables that you don't want to penalize.
- pf.X
A multiplicative factor for the penalty applied to each coefficient.
If supplied, pf.X
must be a numeric vector of the same length as ind.col
.
Default is all 1
. The purpose of pf.X
is to apply differential
penalization if some coefficients are thought to be more likely than others
to be in the model. Setting SOME to 0 allows to have unpenalized coefficients.
- pf.covar
Same as pf.X
, but for covar.train
.
You might want to set some to 0 as variables with large effects can mask
small effects in penalized regression.
- alphas
The elastic-net mixing parameter that controls the relative
contribution from the lasso (l1) and the ridge (l2) penalty. The penalty is
defined as $$ \alpha||\beta||_1 + (1-\alpha)/2||\beta||_2^2.$$
alpha = 1
is the lasso penalty and alpha
in between 0
(1e-4
) and 1
is the elastic-net penalty. Default is 1
. You can
pass multiple values, and only one will be used (optimized by grid-search).
- power_scale
When using lasso (alpha = 1), penalization to apply that
is equivalent to scaling genotypes dividing by (standard deviation)^power_scale.
Default is 1 and corresponding to standard scaling. Using 0 would correspond
to using unscaled variables and using 0.5 is Pareto scaling. If you e.g. use
power_scale = c(0, 0.5, 1)
, the best value in CMSA will be used
(just like with alphas
).
- power_adaptive
Multiplicative penalty factor to apply to variables
in the form of 1 / m_j^power_adaptive, where m_j is the marginal statistic
for variable j. Default is 0, which effectively disables this option.
If you e.g. use power_adaptive = c(0, 0.5, 1.5)
, the best value in CMSA
will be used (just like with alphas
).
- K
Number of sets used in the Cross-Model Selection and Averaging
(CMSA) procedure. Default is 10
.
- ind.sets
Integer vectors of values between 1
and K
specifying
which set each index of the training set is in. Default randomly assigns
these values but it can be useful to set this vector for reproducibility,
or if you want to refine the grid-search over alphas
using the same sets.
- nlambda
The number of lambda values. Default is 200
.
- nlam.min
Minimum number of lambda values to investigate. Default is 50
.
- n.abort
Number of lambda values for which prediction on the validation
set must decrease before stopping. Default is 10
.
- dfmax
Upper bound for the number of nonzero coefficients. Default is
50e3
because, for large data sets, computational burden may be
heavy for models with a large number of nonzero coefficients.
- warn
Whether to warn if some models may not have reached a minimum.
Default is TRUE
.
- ncores
Number of cores used. Default doesn't use parallelism.
You may use nb_cores.
- ...
Arguments passed on to COPY_biglasso_main
lambda.min.ratio
The smallest value for lambda, as a fraction of
lambda.max. Default is .0001
if the number of observations is larger than
the number of variables and .001
otherwise.
eps
Convergence threshold for inner coordinate descent.
The algorithm iterates until the maximum change in the objective after any
coefficient update is less than eps
times the null deviance.
Default value is 1e-5
.
max.iter
Maximum number of iterations. Default is 1000
.
return.all
Deprecated. Now always return all models.