# -*- encoding: utf-8 -*-
"""
Regression model.
:copyright: (c) 2016 H2O.ai
:license: Apache License Version 2.0 (see LICENSE for details)
"""
from __future__ import absolute_import, division, print_function, unicode_literals
import imp
from h2o.model.confusion_matrix import ConfusionMatrix
from h2o.utils.backward_compatibility import backwards_compatible
from h2o.utils.compatibility import * # NOQA
from h2o.utils.typechecks import assert_is_type, assert_satisfies, numeric
[docs]class MetricsBase(backwards_compatible()):
"""
A parent class to house common metrics available for the various Metrics types.
The methods here are available across different model categories.
"""
def __init__(self, metric_json, on=None, algo=""):
super(MetricsBase, self).__init__()
# Yep, it's messed up...
if isinstance(metric_json, MetricsBase): metric_json = metric_json._metric_json
self._metric_json = metric_json
# train and valid and xval are not mutually exclusive -- could have a test. train and
# valid only make sense at model build time.
self._on_train = False
self._on_valid = False
self._on_xval = False
self._algo = algo
if on == "training_metrics":
self._on_train = True
elif on == "validation_metrics":
self._on_valid = True
elif on == "cross_validation_metrics":
self._on_xval = True
elif on is None:
pass
else:
raise ValueError("on expected to be train,valid,or xval. Got: " + str(on))
@classmethod
[docs] def make(cls, kvs):
"""Factory method to instantiate a MetricsBase object from the list of key-value pairs."""
return cls(metric_json=dict(kvs))
def __repr__(self):
# FIXME !!! __repr__ should never print anything, but return a string
self.show()
return ""
# TODO: convert to actual fields list
def __getitem__(self, key):
return self._metric_json.get(key)
@staticmethod
def _has(dictionary, key):
return key in dictionary and dictionary[key] is not None
[docs] def show(self):
"""Display a short summary of the metrics."""
metric_type = self._metric_json['__meta']['schema_type']
types_w_glm = ['ModelMetricsRegressionGLM', 'ModelMetricsBinomialGLM']
types_w_clustering = ['ModelMetricsClustering']
types_w_mult = ['ModelMetricsMultinomial']
types_w_bin = ['ModelMetricsBinomial', 'ModelMetricsBinomialGLM']
types_w_r2 = ['ModelMetricsRegressionGLM']
types_w_mean_residual_deviance = ['ModelMetricsRegressionGLM', 'ModelMetricsRegression']
types_w_mean_absolute_error = ['ModelMetricsRegressionGLM', 'ModelMetricsRegression']
types_w_logloss = types_w_bin + types_w_mult
types_w_dim = ["ModelMetricsGLRM"]
print()
print(metric_type + ": " + self._algo)
reported_on = "** Reported on {} data. **"
if self._on_train:
print(reported_on.format("train"))
elif self._on_valid:
print(reported_on.format("validation"))
elif self._on_xval:
print(reported_on.format("cross-validation"))
else:
print(reported_on.format("test"))
print()
print("MSE: " + str(self.mse()))
print("RMSE: " + str(self.rmse()))
if metric_type in types_w_mean_absolute_error:
print("MAE: " + str(self.mae()))
print("RMSLE: " + str(self.rmsle()))
if metric_type in types_w_r2:
print("R^2: " + str(self.r2()))
if metric_type in types_w_mean_residual_deviance:
print("Mean Residual Deviance: " + str(self.mean_residual_deviance()))
if metric_type in types_w_logloss:
print("LogLoss: " + str(self.logloss()))
if metric_type == 'ModelMetricsBinomial':
# second element for first threshold is the actual mean per class error
print("Mean Per-Class Error: %s" % self.mean_per_class_error()[0][1])
if metric_type == 'ModelMetricsMultinomial':
print("Mean Per-Class Error: " + str(self.mean_per_class_error()))
if metric_type in types_w_glm:
print("Null degrees of freedom: " + str(self.null_degrees_of_freedom()))
print("Residual degrees of freedom: " + str(self.residual_degrees_of_freedom()))
print("Null deviance: " + str(self.null_deviance()))
print("Residual deviance: " + str(self.residual_deviance()))
print("AIC: " + str(self.aic()))
if metric_type in types_w_bin:
print("AUC: " + str(self.auc()))
print("Gini: " + str(self.gini()))
self.confusion_matrix().show()
self._metric_json["max_criteria_and_metric_scores"].show()
if self.gains_lift():
print(self.gains_lift())
if metric_type in types_w_mult:
self.confusion_matrix().show()
self.hit_ratio_table().show()
if metric_type in types_w_clustering:
print("Total Within Cluster Sum of Square Error: " + str(self.tot_withinss()))
print("Total Sum of Square Error to Grand Mean: " + str(self.totss()))
print("Between Cluster Sum of Square Error: " + str(self.betweenss()))
self._metric_json['centroid_stats'].show()
if metric_type in types_w_dim:
print("Sum of Squared Error (Numeric): " + str(self.num_err()))
print("Misclassification Error (Categorical): " + str(self.cat_err()))
[docs] def r2(self):
"""The R squared coefficient."""
return self._metric_json["r2"]
[docs] def logloss(self):
"""Log loss."""
return self._metric_json["logloss"]
[docs] def nobs(self):
"""The number of observations."""
return self._metric_json["nobs"]
[docs] def mean_residual_deviance(self):
"""The mean residual deviance for this set of metrics."""
return self._metric_json["mean_residual_deviance"]
[docs] def auc(self):
"""The AUC for this set of metrics."""
return self._metric_json['AUC']
[docs] def aic(self):
"""The AIC for this set of metrics."""
return self._metric_json['AIC']
[docs] def gini(self):
"""Gini coefficient."""
return self._metric_json['Gini']
[docs] def mse(self):
"""The MSE for this set of metrics."""
return self._metric_json['MSE']
[docs] def rmse(self):
"""The RMSE for this set of metrics."""
return self._metric_json['RMSE']
[docs] def mae(self):
"""The MAE for this set of metrics."""
return self._metric_json['mae']
[docs] def rmsle(self):
"""The RMSLE for this set of metrics."""
return self._metric_json['rmsle']
[docs] def residual_deviance(self):
"""The residual deviance if the model has it, otherwise None."""
if MetricsBase._has(self._metric_json, "residual_deviance"):
return self._metric_json["residual_deviance"]
return None
[docs] def residual_degrees_of_freedom(self):
"""The residual DoF if the model has residual deviance, otherwise None."""
if MetricsBase._has(self._metric_json, "residual_degrees_of_freedom"):
return self._metric_json["residual_degrees_of_freedom"]
return None
[docs] def null_deviance(self):
"""The null deviance if the model has residual deviance, otherwise None."""
if MetricsBase._has(self._metric_json, "null_deviance"):
return self._metric_json["null_deviance"]
return None
[docs] def null_degrees_of_freedom(self):
"""The null DoF if the model has residual deviance, otherwise None."""
if MetricsBase._has(self._metric_json, "null_degrees_of_freedom"):
return self._metric_json["null_degrees_of_freedom"]
return None
[docs] def mean_per_class_error(self):
"""The mean per class error."""
return self._metric_json['mean_per_class_error']
# Deprecated functions; left here for backward compatibility
_bcim = {
"giniCoef": lambda self, *args, **kwargs: self.gini(*args, **kwargs)
}
[docs]class H2ORegressionModelMetrics(MetricsBase):
"""
This class provides an API for inspecting the metrics returned by a regression model.
It is possible to retrieve the R^2 (1 - MSE/variance) and MSE.
"""
def __init__(self, metric_json, on=None, algo=""):
super(H2ORegressionModelMetrics, self).__init__(metric_json, on, algo)
[docs]class H2OClusteringModelMetrics(MetricsBase):
def __init__(self, metric_json, on=None, algo=""):
super(H2OClusteringModelMetrics, self).__init__(metric_json, on, algo)
[docs] def tot_withinss(self):
"""The Total Within Cluster Sum-of-Square Error, or None if not present."""
if MetricsBase._has(self._metric_json, "tot_withinss"):
return self._metric_json["tot_withinss"]
return None
[docs] def totss(self):
"""The Total Sum-of-Square Error to Grand Mean, or None if not present."""
if MetricsBase._has(self._metric_json, "totss"):
return self._metric_json["totss"]
return None
[docs] def betweenss(self):
"""The Between Cluster Sum-of-Square Error, or None if not present."""
if MetricsBase._has(self._metric_json, "betweenss"):
return self._metric_json["betweenss"]
return None
[docs]class H2OMultinomialModelMetrics(MetricsBase):
def __init__(self, metric_json, on=None, algo=""):
super(H2OMultinomialModelMetrics, self).__init__(metric_json, on, algo)
[docs] def confusion_matrix(self):
"""Returns a confusion matrix based of H2O's default prediction threshold for a dataset."""
return self._metric_json['cm']['table']
[docs] def hit_ratio_table(self):
"""Retrieve the Hit Ratios."""
return self._metric_json['hit_ratio_table']
[docs]class H2OBinomialModelMetrics(MetricsBase):
"""
This class is essentially an API for the AUC object.
This class contains methods for inspecting the AUC for different criteria.
To input the different criteria, use the static variable `criteria`.
"""
def __init__(self, metric_json, on=None, algo=""):
"""
Create a new Binomial Metrics object (essentially a wrapper around some json)
:param metric_json: A blob of json holding all of the needed information
:param on_train: Metrics built on training data (default is False)
:param on_valid: Metrics built on validation data (default is False)
:param on_xval: Metrics built on cross validation data (default is False)
:param algo: The algorithm the metrics are based off of (e.g. deeplearning, gbm, etc.)
:returns: A new H2OBinomialModelMetrics object.
"""
super(H2OBinomialModelMetrics, self).__init__(metric_json, on, algo)
[docs] def F1(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The F1 for the given set of thresholds.
"""
return self.metric("f1", thresholds=thresholds)
[docs] def F2(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The F2 for this set of metrics and thresholds.
"""
return self.metric("f2", thresholds=thresholds)
[docs] def F0point5(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The F0.5 for this set of metrics and thresholds.
"""
return self.metric("f0point5", thresholds=thresholds)
[docs] def accuracy(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The accuracy for this set of metrics and thresholds.
"""
return self.metric("accuracy", thresholds=thresholds)
[docs] def error(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The error for this set of metrics and thresholds.
"""
return 1 - self.metric("accuracy", thresholds=thresholds)
[docs] def precision(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The precision for this set of metrics and thresholds.
"""
return self.metric("precision", thresholds=thresholds)
[docs] def tpr(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The True Postive Rate.
"""
return self.metric("tpr", thresholds=thresholds)
[docs] def tnr(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The True Negative Rate.
"""
return self.metric("tnr", thresholds=thresholds)
[docs] def fnr(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The False Negative Rate.
"""
return self.metric("fnr", thresholds=thresholds)
[docs] def fpr(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The False Positive Rate.
"""
return self.metric("fpr", thresholds=thresholds)
[docs] def recall(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: Recall for this set of metrics and thresholds.
"""
return self.metric("tpr", thresholds=thresholds)
[docs] def sensitivity(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: Sensitivity or True Positive Rate for this set of metrics and thresholds.
"""
return self.metric("tpr", thresholds=thresholds)
[docs] def fallout(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The fallout (same as False Positive Rate) for this set of metrics and thresholds.
"""
return self.metric("fpr", thresholds=thresholds)
[docs] def missrate(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: THe miss rate (same as False Negative Rate).
"""
return self.metric("fnr", thresholds=thresholds)
[docs] def specificity(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The specificity (same as True Negative Rate).
"""
return self.metric("tnr", thresholds=thresholds)
[docs] def mcc(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: The absolute MCC (a value between 0 and 1, 0 being totally dissimilar, 1 being identical).
"""
return self.metric("absolute_mcc", thresholds=thresholds)
[docs] def max_per_class_error(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: Return 1 - min(per class accuracy).
"""
return 1 - self.metric("min_per_class_accuracy", thresholds=thresholds)
[docs] def mean_per_class_error(self, thresholds=None):
"""
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then the
thresholds in this set of metrics will be used.
:returns: mean per class error.
"""
return [[x[0], 1 - x[1]] for x in self.metric("mean_per_class_accuracy", thresholds=thresholds)]
[docs] def metric(self, metric, thresholds=None):
"""
:param str metric: The desired metric.
:param thresholds: thresholds parameter must be a list (i.e. [0.01, 0.5, 0.99]). If None, then
the thresholds in this set of metrics will be used.
:returns: The set of metrics for the list of thresholds.
"""
assert_is_type(thresholds, None, [numeric])
if not thresholds: thresholds = [self.find_threshold_by_max_metric(metric)]
thresh2d = self._metric_json['thresholds_and_metric_scores']
metrics = []
for t in thresholds:
idx = self.find_idx_by_threshold(t)
metrics.append([t, thresh2d[metric][idx]])
return metrics
[docs] def plot(self, type="roc", server=False):
"""
Produce the desired metric plot.
:param type: the type of metric plot (currently, only ROC supported).
:param server: if True, generate plot inline using matplotlib's "Agg" backend.
:returns: None
"""
# TODO: add more types (i.e. cutoffs)
assert_is_type(type, "roc")
# check for matplotlib. exit if absent.
try:
imp.find_module('matplotlib')
import matplotlib
if server: matplotlib.use('Agg', warn=False)
import matplotlib.pyplot as plt
except ImportError:
print("matplotlib is required for this function!")
return
if type == "roc":
plt.xlabel('False Positive Rate (FPR)')
plt.ylabel('True Positive Rate (TPR)')
plt.title('ROC Curve')
plt.text(0.5, 0.5, r'AUC={0:.4f}'.format(self._metric_json["AUC"]))
plt.plot(self.fprs, self.tprs, 'b--')
plt.axis([0, 1, 0, 1])
if not server: plt.show()
@property
def fprs(self):
"""
Return all false positive rates for all threshold values.
:returns: a list of false positive rates.
"""
return self._metric_json["thresholds_and_metric_scores"]["fpr"]
@property
def tprs(self):
"""
Return all true positive rates for all threshold values.
:returns: a list of true positive rates.
"""
return self._metric_json["thresholds_and_metric_scores"]["tpr"]
[docs] def confusion_matrix(self, metrics=None, thresholds=None):
"""
Get the confusion matrix for the specified metric
:param metrics: A string (or list of strings) in {"min_per_class_accuracy", "absolute_mcc", "tnr", "fnr", "fpr",
"tpr", "precision", "accuracy", "f0point5", "f2", "f1","mean_per_class_accuracy"}
:param thresholds: A value (or list of values) between 0 and 1
:returns: a list of ConfusionMatrix objects (if there are more than one to return), or a single ConfusionMatrix
(if there is only one).
"""
# make lists out of metrics and thresholds arguments
if metrics is None and thresholds is None: metrics = ["f1"]
if isinstance(metrics, list):
metrics_list = metrics
elif metrics is None:
metrics_list = []
else:
metrics_list = [metrics]
if isinstance(thresholds, list):
thresholds_list = thresholds
elif thresholds is None:
thresholds_list = []
else:
thresholds_list = [thresholds]
# error check the metrics_list and thresholds_list
assert_is_type(thresholds_list, [numeric])
assert_satisfies(thresholds_list, all(0 <= t <= 1 for t in thresholds_list))
if not all(m.lower() in ["min_per_class_accuracy", "absolute_mcc", "precision", "recall", "specificity",
"accuracy", "f0point5", "f2", "f1", "mean_per_class_accuracy"] for m in metrics_list):
raise ValueError(
"The only allowable metrics are min_per_class_accuracy, absolute_mcc, precision, accuracy, f0point5, "
"f2, f1, mean_per_class_accuracy")
# make one big list that combines the thresholds and metric-thresholds
metrics_thresholds = [self.find_threshold_by_max_metric(m) for m in metrics_list]
for mt in metrics_thresholds:
thresholds_list.append(mt)
thresh2d = self._metric_json['thresholds_and_metric_scores']
actual_thresholds = [float(e[0]) for i, e in enumerate(thresh2d.cell_values)]
cms = []
for t in thresholds_list:
idx = self.find_idx_by_threshold(t)
row = thresh2d.cell_values[idx]
tns = row[11]
fns = row[12]
fps = row[13]
tps = row[14]
p = tps + fns
n = tns + fps
c0 = n - fps
c1 = p - tps
if t in metrics_thresholds:
m = metrics_list[metrics_thresholds.index(t)]
table_header = "Confusion Matrix (Act/Pred) for max " + m + " @ threshold = " + str(
actual_thresholds[idx])
else:
table_header = "Confusion Matrix (Act/Pred) @ threshold = " + str(actual_thresholds[idx])
cms.append(ConfusionMatrix(cm=[[c0, fps], [c1, tps]], domains=self._metric_json['domain'],
table_header=table_header))
if len(cms) == 1:
return cms[0]
else:
return cms
[docs] def find_threshold_by_max_metric(self, metric):
"""
:param metric: A string in {"min_per_class_accuracy", "absolute_mcc", "precision", "recall", "specificity",
"accuracy", "f0point5", "f2", "f1", "mean_per_class_accuracy"}.
:returns: the threshold at which the given metric is maximal.
"""
crit2d = self._metric_json['max_criteria_and_metric_scores']
for e in crit2d.cell_values:
if e[0] == "max " + metric.lower():
return e[1]
raise ValueError("No metric " + str(metric.lower()))
[docs] def find_idx_by_threshold(self, threshold):
"""
Retrieve the index in this metric's threshold list at which the given threshold is located.
:param threshold: Find the index of this input threshold.
:returns: the index
:raises ValueError: if no such index can be found.
"""
assert_is_type(threshold, numeric)
thresh2d = self._metric_json['thresholds_and_metric_scores']
for i, e in enumerate(thresh2d.cell_values):
t = float(e[0])
if abs(t - threshold) < 0.00000001 * max(t, threshold):
return i
if threshold >= 0 and threshold <= 1:
thresholds = [float(e[0]) for i, e in enumerate(thresh2d.cell_values)]
threshold_diffs = [abs(t - threshold) for t in thresholds]
closest_idx = threshold_diffs.index(min(threshold_diffs))
closest_threshold = thresholds[closest_idx]
print("Could not find exact threshold {0}; using closest threshold found {1}."
.format(threshold, closest_threshold))
return closest_idx
raise ValueError("Threshold must be between 0 and 1, but got {0} ".format(threshold))
[docs] def gains_lift(self):
"""Retrieve the Gains/Lift table."""
if 'gains_lift_table' in self._metric_json:
return self._metric_json['gains_lift_table']
return None
[docs]class H2OAutoEncoderModelMetrics(MetricsBase):
def __init__(self, metric_json, on=None, algo=""):
super(H2OAutoEncoderModelMetrics, self).__init__(metric_json, on, algo)
[docs]class H2ODimReductionModelMetrics(MetricsBase):
def __init__(self, metric_json, on=None, algo=""):
super(H2ODimReductionModelMetrics, self).__init__(metric_json, on, algo)
[docs] def num_err(self):
"""Sum of Squared Error over non-missing numeric entries, or None if not present."""
if MetricsBase._has(self._metric_json, "numerr"):
return self._metric_json["numerr"]
return None
[docs] def cat_err(self):
"""The Number of Misclassified categories over non-missing categorical entries, or None if not present."""
if MetricsBase._has(self._metric_json, "caterr"):
return self._metric_json["caterr"]
return None
[docs]class H2OWordEmbeddingModelMetrics(MetricsBase):
def __init__(self, metric_json, on=None, algo=""):
super(H2OWordEmbeddingModelMetrics, self).__init__(metric_json, on, algo)