h2o.adaBoost function

Build an AdaBoost model

Build an AdaBoost model

Builds an AdaBoost model on an H2OFrame.

h2o.adaBoost( x, y, training_frame, model_id = NULL, ignore_const_cols = TRUE, categorical_encoding = c("AUTO", "Enum", "OneHotInternal", "OneHotExplicit", "Binary", "Eigen", "LabelEncoder", "SortByResponse", "EnumLimited"), weights_column = NULL, nlearners = 50, weak_learner = c("AUTO", "DRF", "GLM", "GBM", "DEEP_LEARNING"), learn_rate = 0.5, weak_learner_params = NULL, seed = -1 )

Arguments

  • x: (Optional) A vector containing the names or indices of the predictor variables to use in building the model. If x is missing, then all columns except y are used.
  • y: The name or column index of the response variable in the data. The response must be either a numeric or a categorical/factor variable. If the response is numeric, then a regression model will be trained, otherwise it will train a classification model.
  • training_frame: Id of the training data frame.
  • model_id: Destination id for this model; auto-generated if not specified.
  • ignore_const_cols: Logical. Ignore constant columns. Defaults to TRUE.
  • categorical_encoding: Encoding scheme for categorical features Must be one of: "AUTO", "Enum", "OneHotInternal", "OneHotExplicit", "Binary", "Eigen", "LabelEncoder", "SortByResponse", "EnumLimited". Defaults to AUTO.
  • weights_column: Column with observation weights. Giving some observation a weight of zero is equivalent to excluding it from the dataset; giving an observation a relative weight of 2 is equivalent to repeating that row twice. Negative weights are not allowed. Note: Weights are per-row observation weights and do not increase the size of the data frame. This is typically the number of times a row is repeated, but non-integer values are supported as well. During training, rows with higher weights matter more, due to the larger loss function pre-factor. If you set weight = 0 for a row, the returned prediction frame at that row is zero and this is incorrect. To get an accurate prediction, remove all rows with weight == 0.
  • nlearners: Number of AdaBoost weak learners. Defaults to 50.
  • weak_learner: Choose a weak learner type. Defaults to AUTO, which means DRF. Must be one of: "AUTO", "DRF", "GLM", "GBM", "DEEP_LEARNING". Defaults to AUTO.
  • learn_rate: Learning rate (from 0.0 to 1.0) Defaults to 0.5.
  • weak_learner_params: Customized parameters for the weak_learner algorithm. E.g list(ntrees=3, max_depth=2, histogram_type='UniformAdaptive'))
  • seed: Seed for random numbers (affects certain parts of the algo that are stochastic and those might or might not be enabled by default). Defaults to -1 (time-based random number).

Returns

Creates a H2OModel object of the right type.

Examples

## Not run: library(h2o) h2o.init() # Import the airlines dataset f <- "https://s3.amazonaws.com/h2o-public-test-data/smalldata/prostate/prostate.csv" data <- h2o.importFile(f) # Set predictors and response; set response as a factor data["CAPSULE"] <- as.factor(data["CAPSULE"]) predictors <- c("AGE","RACE","DPROS","DCAPS","PSA","VOL","GLEASON") response <- "CAPSULE" # Train the AdaBoost model h2o_adaboost <- h2o.adaBoost(x = predictors, y = response, training_frame = data, seed = 1234) ## End(Not run)

See Also

predict.H2OModel for prediction

  • Maintainer: Tomas Fryda
  • License: Apache License (== 2.0)
  • Last published: 2024-01-11