RegressionEvaluator¶

class pyspark.ml.evaluation.RegressionEvaluator(*, predictionCol: str = 'prediction', labelCol: str = 'label', metricName: RegressionEvaluatorMetricType = 'rmse', weightCol: Optional[str] = None, throughOrigin: bool = False)¶

Evaluator for Regression, which expects input columns prediction, label and an optional weight column.

Examples

>>> scoreAndLabels = [(-28.98343821, -27.0), (20.21491975, 21.5),
...   (-25.98418959, -22.0), (30.69731842, 33.0), (74.69283752, 71.0)]
>>> dataset = spark.createDataFrame(scoreAndLabels, ["raw", "label"])
...
>>> evaluator = RegressionEvaluator()
>>> evaluator.setPredictionCol("raw")
RegressionEvaluator...
>>> evaluator.evaluate(dataset)
2.842...
>>> evaluator.evaluate(dataset, {evaluator.metricName: "r2"})
0.993...
>>> evaluator.evaluate(dataset, {evaluator.metricName: "mae"})
2.649...
>>> re_path = temp_path + "/re"
>>> evaluator.save(re_path)
>>> evaluator2 = RegressionEvaluator.load(re_path)
>>> str(evaluator2.getPredictionCol())
'raw'
>>> scoreAndLabelsAndWeight = [(-28.98343821, -27.0, 1.0), (20.21491975, 21.5, 0.8),
...   (-25.98418959, -22.0, 1.0), (30.69731842, 33.0, 0.6), (74.69283752, 71.0, 0.2)]
>>> dataset = spark.createDataFrame(scoreAndLabelsAndWeight, ["raw", "label", "weight"])
...
>>> evaluator = RegressionEvaluator(predictionCol="raw", weightCol="weight")
>>> evaluator.evaluate(dataset)
2.740...
>>> evaluator.getThroughOrigin()
False

Methods

`clear`(param)	Clears a param from the param map if it has been explicitly set.
`copy`([extra])	Creates a copy of this instance with the same uid and some extra params.
`evaluate`(dataset[, params])	Evaluates the output with optional parameters.
`explainParam`(param)	Explains a single param and returns its name, doc, and optional default value and user-supplied value in a string.
`explainParams`()	Returns the documentation of all params with their optionally default values and user-supplied values.
`extractParamMap`([extra])	Extracts the embedded default param values and user-supplied values, and then merges them with extra values from input into a flat param map, where the latter value is used if there exist conflicts, i.e., with ordering: default param values < user-supplied values < extra.
`getLabelCol`()	Gets the value of labelCol or its default value.
`getMetricName`()	Gets the value of metricName or its default value.
`getOrDefault`(param)	Gets the value of a param in the user-supplied param map or its default value.
`getParam`(paramName)	Gets a param by its name.
`getPredictionCol`()	Gets the value of predictionCol or its default value.
`getThroughOrigin`()	Gets the value of throughOrigin or its default value.
`getWeightCol`()	Gets the value of weightCol or its default value.
`hasDefault`(param)	Checks whether a param has a default value.
`hasParam`(paramName)	Tests whether this instance contains a param with a given (string) name.
`isDefined`(param)	Checks whether a param is explicitly set by user or has a default value.
`isLargerBetter`()	Indicates whether the metric returned by `evaluate()` should be maximized (True, default) or minimized (False).
`isSet`(param)	Checks whether a param is explicitly set by user.
`load`(path)	Reads an ML instance from the input path, a shortcut of read().load(path).
`read`()	Returns an MLReader instance for this class.
`save`(path)	Save this ML instance to the given path, a shortcut of ‘write().save(path)’.
`set`(param, value)	Sets a parameter in the embedded param map.
`setLabelCol`(value)	Sets the value of `labelCol`.
`setMetricName`(value)	Sets the value of `metricName`.
`setParams`(self, \*[, predictionCol, …])	Sets params for regression evaluator.
`setPredictionCol`(value)	Sets the value of `predictionCol`.
`setThroughOrigin`(value)	Sets the value of `throughOrigin`.
`setWeightCol`(value)	Sets the value of `weightCol`.
`write`()	Returns an MLWriter instance for this ML instance.

Attributes

`labelCol`
`metricName`
`params`	Returns all params ordered by name.
`predictionCol`
`throughOrigin`
`weightCol`

Methods Documentation

clear(param: pyspark.ml.param.Param) → None¶: Clears a param from the param map if it has been explicitly set.

copy(extra: Optional[ParamMap] = None) → JP¶

Creates a copy of this instance with the same uid and some extra params. This implementation first calls Params.copy and then make a copy of the companion Java pipeline component with extra params. So both the Python wrapper and the Java pipeline component get copied.

Parameters

extradict, optional: Extra parameters to copy to the new instance

Returns

JavaParams: Copy of this instance

evaluate(dataset: pyspark.sql.dataframe.DataFrame, params: Optional[ParamMap] = None) → float¶

Evaluates the output with optional parameters.

Parameters

datasetpyspark.sql.DataFrame: a dataset that contains labels/observations and predictions
paramsdict, optional: an optional param map that overrides embedded params

Returns

float: metric

explainParam(param: Union[str, pyspark.ml.param.Param]) → str¶: Explains a single param and returns its name, doc, and optional default value and user-supplied value in a string.

explainParams() → str¶: Returns the documentation of all params with their optionally default values and user-supplied values.

extractParamMap(extra: Optional[ParamMap] = None) → ParamMap¶

Extracts the embedded default param values and user-supplied values, and then merges them with extra values from input into a flat param map, where the latter value is used if there exist conflicts, i.e., with ordering: default param values < user-supplied values < extra.

Parameters

extradict, optional: extra param values

Returns

dict: merged param map

getLabelCol() → str¶: Gets the value of labelCol or its default value.

getMetricName() → RegressionEvaluatorMetricType¶: Gets the value of metricName or its default value.

getOrDefault(param: Union[str, pyspark.ml.param.Param[T]]) → Union[Any, T]¶: Gets the value of a param in the user-supplied param map or its default value. Raises an error if neither is set.

getParam(paramName: str) → pyspark.ml.param.Param ¶: Gets a param by its name.

getPredictionCol() → str¶: Gets the value of predictionCol or its default value.

getThroughOrigin() → bool¶: Gets the value of throughOrigin or its default value.

getWeightCol() → str¶: Gets the value of weightCol or its default value.

hasDefault(param: Union[str, pyspark.ml.param.Param[Any]]) → bool¶: Checks whether a param has a default value.

hasParam(paramName: str) → bool¶: Tests whether this instance contains a param with a given (string) name.

isDefined(param: Union[str, pyspark.ml.param.Param[Any]]) → bool¶: Checks whether a param is explicitly set by user or has a default value.

isLargerBetter() → bool¶: Indicates whether the metric returned by evaluate() should be maximized (True, default) or minimized (False). A given evaluator may support multiple metrics which may be maximized or minimized.

isSet(param: Union[str, pyspark.ml.param.Param[Any]]) → bool¶: Checks whether a param is explicitly set by user.

classmethod load(path: str) → RL¶: Reads an ML instance from the input path, a shortcut of read().load(path).

classmethod read() → pyspark.ml.util.JavaMLReader[RL]¶: Returns an MLReader instance for this class.

save(path: str) → None¶: Save this ML instance to the given path, a shortcut of ‘write().save(path)’.

set(param: pyspark.ml.param.Param, value: Any) → None¶: Sets a parameter in the embedded param map.

setLabelCol(value: str) → pyspark.ml.evaluation.RegressionEvaluator ¶: Sets the value of labelCol.

setMetricName(value: RegressionEvaluatorMetricType) → RegressionEvaluator¶: Sets the value of metricName.

setParams(self, \*, predictionCol="prediction", labelCol="label", metricName="rmse", weightCol=None, throughOrigin=False)¶: Sets params for regression evaluator.

setPredictionCol(value: str) → pyspark.ml.evaluation.RegressionEvaluator ¶: Sets the value of predictionCol.

setThroughOrigin(value: bool) → pyspark.ml.evaluation.RegressionEvaluator ¶: Sets the value of throughOrigin.

setWeightCol(value: str) → pyspark.ml.evaluation.RegressionEvaluator ¶: Sets the value of weightCol.

write() → pyspark.ml.util.JavaMLWriter¶: Returns an MLWriter instance for this ML instance.

Attributes Documentation

labelCol = Param(parent='undefined', name='labelCol', doc='label column name.')¶

metricName: pyspark.ml.param.Param[RegressionEvaluatorMetricType] = Param(parent='undefined', name='metricName', doc='metric name in evaluation - one of:\n rmse - root mean squared error (default)\n mse - mean squared error\n r2 - r^2 metric\n mae - mean absolute error\n var - explained variance.')¶

params¶: Returns all params ordered by name. The default implementation uses dir() to get all attributes of type Param.

predictionCol = Param(parent='undefined', name='predictionCol', doc='prediction column name.')¶

throughOrigin: pyspark.ml.param.Param[bool] = Param(parent='undefined', name='throughOrigin', doc='whether the regression is through the origin.')¶

weightCol = Param(parent='undefined', name='weightCol', doc='weight column name. If this is not set or empty, we treat all instance weights as 1.0.')¶

BinaryClassificationEvaluator

MulticlassClassificationEvaluator