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picasso (version 2.0.1)

predict.poisson: Prediction Method for an Object with S3 Class "poisson"

Description

Predict responses for new data using fitted models.

Usage

# S3 method for poisson
predict(object, newdata, lambda.idx = NULL, p.pred.idx = NULL,
  type = "response", s = NULL, newoffset = NULL, ...)

Value

Return type depends on type:

  • "response" (default): numeric matrix of predicted Poisson means \(\hat{\mu} = \exp(o_{new} + \hat{\beta}_0 + X \hat{\beta})\).

  • "link": numeric matrix of log-means \(o_{new} + \hat{\beta}_0 + X \hat{\beta}\).

  • "nonzero": list of integer vectors of nonzero coefficient indices, one element per selected lambda.

Rows correspond to observations; columns correspond to lambda.idx (or s values when s is specified).

Arguments

object

An object with S3 class "poisson".

newdata

Nonempty finite numeric matrix of new observations for prediction (\(n_{new} \times d\)) with the same number of columns as the fitted design.

lambda.idx

Positive integer indices of regularization parameters along the solution path used for prediction. By default, at most the first three fitted path points are used.

p.pred.idx

Optional row indices to subset returned predictions. NULL returns every prediction row.

type

Type of prediction. "response" (default) returns predicted Poisson means; "link" returns the log-mean; "nonzero" returns nonzero variable indices.

s

Optional nonempty vector of finite non-negative lambda values; see predict.gaussian.

newoffset

Optional finite numeric vector with one offset per row of newdata. It is required for response or link prediction when object was fitted with offset; type = "nonzero" does not use it. For a model fitted without offset, the default is a vector of zeros.

...

Arguments to be passed to methods.

Author

Jason Ge, Xingguo Li, Haoming Jiang, Mengdi Wang, Tong Zhang, Han Liu and Tuo Zhao
Maintainer: Tuo Zhao <tourzhao@gatech.edu>

Details

predict.poisson returns predicted Poisson means for newdata using fitted coefficients from object: $$ \hat{\mu} = e^{o_{new} + \hat{\beta}_0 + X_{new} \hat{\beta}}. $$

See Also

picasso and picasso-package.