Package org.apache.spark.ml.tuning
Class CrossValidatorModel
- All Implemented Interfaces:
Serializable
,org.apache.spark.internal.Logging
,Params
,HasSeed
,CrossValidatorParams
,ValidatorParams
,Identifiable
,MLWritable
public class CrossValidatorModel
extends Model<CrossValidatorModel>
implements CrossValidatorParams, MLWritable
CrossValidatorModel contains the model with the highest average cross-validation
metric across folds and uses this model to transform input data. CrossValidatorModel
also tracks the metrics for each param map evaluated.
param: bestModel The best model selected from k-fold cross validation.
param: avgMetrics Average cross-validation metrics for each paramMap in
CrossValidator.estimatorParamMaps
, in the corresponding order.
- See Also:
-
Nested Class Summary
Modifier and TypeClassDescriptionstatic final class
Writer for CrossValidatorModel.Nested classes/interfaces inherited from interface org.apache.spark.internal.Logging
org.apache.spark.internal.Logging.LogStringContext, org.apache.spark.internal.Logging.SparkShellLoggingFilter
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Method Summary
Modifier and TypeMethodDescriptiondouble[]
Model<?>
Creates a copy of this instance with the same UID and some extra params.param for the estimator to be validatedparam for estimator param mapsparam for the evaluator used to select hyper-parameters that maximize the validated metricfoldCol()
Param for the column name of user specified fold number.boolean
static CrossValidatorModel
numFolds()
Param for number of folds for cross validation.static MLReader<CrossValidatorModel>
read()
final LongParam
seed()
Param for random seed.Model<?>[][]
toString()
Transforms the input dataset.transformSchema
(StructType schema) Check transform validity and derive the output schema from the input schema.uid()
An immutable unique ID for the object and its derivatives.write()
Returns anMLWriter
instance for this ML instance.Methods inherited from class org.apache.spark.ml.Transformer
transform, transform, transform
Methods inherited from class org.apache.spark.ml.PipelineStage
params
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface org.apache.spark.ml.tuning.CrossValidatorParams
getFoldCol, getNumFolds
Methods inherited from interface org.apache.spark.internal.Logging
initializeForcefully, initializeLogIfNecessary, initializeLogIfNecessary, initializeLogIfNecessary$default$2, isTraceEnabled, log, logDebug, logDebug, logDebug, logDebug, logError, logError, logError, logError, logInfo, logInfo, logInfo, logInfo, logName, LogStringContext, logTrace, logTrace, logTrace, logTrace, logWarning, logWarning, logWarning, logWarning, org$apache$spark$internal$Logging$$log_, org$apache$spark$internal$Logging$$log__$eq, withLogContext
Methods inherited from interface org.apache.spark.ml.util.MLWritable
save
Methods inherited from interface org.apache.spark.ml.param.Params
clear, copyValues, defaultCopy, defaultParamMap, explainParam, explainParams, extractParamMap, extractParamMap, get, getDefault, getOrDefault, getParam, hasDefault, hasParam, isDefined, isSet, onParamChange, paramMap, params, set, set, set, setDefault, setDefault, shouldOwn
Methods inherited from interface org.apache.spark.ml.tuning.ValidatorParams
getEstimator, getEstimatorParamMaps, getEvaluator, logTuningParams, transformSchemaImpl
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Method Details
-
read
-
load
-
numFolds
Description copied from interface:CrossValidatorParams
Param for number of folds for cross validation. Must be >= 2. Default: 3- Specified by:
numFolds
in interfaceCrossValidatorParams
- Returns:
- (undocumented)
-
foldCol
Description copied from interface:CrossValidatorParams
Param for the column name of user specified fold number. Once this is specified,CrossValidator
won't do random k-fold split. Note that this column should be integer type with range [0, numFolds) and Spark will throw exception on out-of-range fold numbers.- Specified by:
foldCol
in interfaceCrossValidatorParams
- Returns:
- (undocumented)
-
estimator
Description copied from interface:ValidatorParams
param for the estimator to be validated- Specified by:
estimator
in interfaceValidatorParams
- Returns:
- (undocumented)
-
estimatorParamMaps
Description copied from interface:ValidatorParams
param for estimator param maps- Specified by:
estimatorParamMaps
in interfaceValidatorParams
- Returns:
- (undocumented)
-
evaluator
Description copied from interface:ValidatorParams
param for the evaluator used to select hyper-parameters that maximize the validated metric- Specified by:
evaluator
in interfaceValidatorParams
- Returns:
- (undocumented)
-
seed
Description copied from interface:HasSeed
Param for random seed. -
uid
Description copied from interface:Identifiable
An immutable unique ID for the object and its derivatives.- Specified by:
uid
in interfaceIdentifiable
- Returns:
- (undocumented)
-
bestModel
-
avgMetrics
public double[] avgMetrics() -
subModels
- Returns:
- submodels represented in two dimension array. The index of outer array is the fold index, and the index of inner array corresponds to the ordering of estimatorParamMaps
- Throws:
IllegalArgumentException
- if subModels are not available. To retrieve subModels, make sure to set collectSubModels to true before fitting.
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hasSubModels
public boolean hasSubModels() -
transform
Description copied from class:Transformer
Transforms the input dataset.- Specified by:
transform
in classTransformer
- Parameters:
dataset
- (undocumented)- Returns:
- (undocumented)
-
transformSchema
Description copied from class:PipelineStage
Check transform validity and derive the output schema from the input schema.We check validity for interactions between parameters during
transformSchema
and raise an exception if any parameter value is invalid. Parameter value checks which do not depend on other parameters are handled byParam.validate()
.Typical implementation should first conduct verification on schema change and parameter validity, including complex parameter interaction checks.
- Specified by:
transformSchema
in classPipelineStage
- Parameters:
schema
- (undocumented)- Returns:
- (undocumented)
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copy
Description copied from interface:Params
Creates a copy of this instance with the same UID and some extra params. Subclasses should implement this method and set the return type properly. SeedefaultCopy()
.- Specified by:
copy
in interfaceParams
- Specified by:
copy
in classModel<CrossValidatorModel>
- Parameters:
extra
- (undocumented)- Returns:
- (undocumented)
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write
Description copied from interface:MLWritable
Returns anMLWriter
instance for this ML instance.- Specified by:
write
in interfaceMLWritable
- Returns:
- (undocumented)
-
toString
- Specified by:
toString
in interfaceIdentifiable
- Overrides:
toString
in classObject
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