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QuaPy/test.py

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4.3 KiB
Python

from sklearn.linear_model import LogisticRegression
from sklearn.svm import LinearSVC
import quapy as qp
import quapy.functional as F
import sys
import numpy as np
#qp.datasets.fetch_reviews('hp')
#qp.datasets.fetch_twitter('sst')
#sys.exit()
from model_selection import GridSearchQ
SAMPLE_SIZE=500
binary = False
svmperf_home = './svm_perf_quantification'
if binary:
dataset = qp.datasets.fetch_reviews('kindle', tfidf=True, min_df=5)
else:
dataset = qp.datasets.fetch_twitter('hcr', for_model_selection=False, min_df=10, pickle=True)
# dataset.training = dataset.training.sampling(SAMPLE_SIZE, 0.2, 0.5, 0.3)
print('dataset loaded')
# training a quantifier
learner = LogisticRegression(max_iter=1000)
# model = qp.method.aggregative.ClassifyAndCount(learner)
model = qp.method.aggregative.AdjustedClassifyAndCount(learner)
# model = qp.method.aggregative.ProbabilisticClassifyAndCount(learner)
# model = qp.method.aggregative.ProbabilisticAdjustedClassifyAndCount(learner)
# model = qp.method.aggregative.ExpectationMaximizationQuantifier(learner)
# model = qp.method.aggregative.ExplicitLossMinimisationBinary(svmperf_home, loss='q', C=100)
# model = qp.method.aggregative.SVMQ(svmperf_home, C=1)
if not binary and isinstance(model, qp.method.aggregative.BinaryQuantifier):
model = qp.method.aggregative.OneVsAll(model)
# Model fit and Evaluation on the test data
# ----------------------------------------------------------------------------
print(f'fitting model {model.__class__.__name__}')
train, val = dataset.training.split_stratified(0.6)
model.fit(train, val_split=val)
# estimating class prevalences
print('quantifying')
prevalences_estim = model.quantify(dataset.test.instances)
prevalences_true = dataset.test.prevalence()
# evaluation (one single prediction)
error = qp.error.mae(prevalences_true, prevalences_estim)
print(f'Evaluation in test (1 eval)')
print(f'true prevalence {F.strprev(prevalences_true)}')
print(f'estim prevalence {F.strprev(prevalences_estim)}')
print(f'mae={error:.3f}')
# Model fit and Evaluation according to the artificial sampling protocol
# ----------------------------------------------------------------------------
max_evaluations = 5000
n_prevpoints = F.get_nprevpoints_approximation(combinations_budget=max_evaluations, n_classes=dataset.n_classes)
n_evaluations = F.num_prevalence_combinations(n_prevpoints, dataset.n_classes)
print(f'the prevalence interval [0,1] will be split in {n_prevpoints} prevalence points for each class, so that\n'
f'the requested maximum number of sample evaluations ({max_evaluations}) is not exceeded.\n'
f'For the {dataset.n_classes} classes this dataset has, this will yield a total of {n_evaluations} evaluations.')
true_prev, estim_prev = qp.evaluation.artificial_sampling_prediction(model, dataset.test, SAMPLE_SIZE, n_prevpoints)
qp.error.SAMPLE_SIZE = SAMPLE_SIZE
print(f'Evaluation according to the artificial sampling protocol ({len(true_prev)} evals)')
for error in qp.error.QUANTIFICATION_ERROR:
score = error(true_prev, estim_prev)
print(f'{error.__name__}={score:.5f}')
# Model selection and Evaluation according to the artificial sampling protocol
# ----------------------------------------------------------------------------
param_grid = {'C': np.logspace(-3,3,7), 'class_weight': ['balanced', None]}
model_selection = GridSearchQ(model,
param_grid=param_grid,
sample_size=SAMPLE_SIZE,
eval_budget=max_evaluations//10,
error='mae',
refit=True,
verbose=True)
# model = model_selection.fit(dataset.training, validation=0.3)
model = model_selection.fit(train, validation=val)
print(f'Model selection: best_params = {model_selection.best_params_}')
print(f'param scores:')
for params, score in model_selection.param_scores_.items():
print(f'\t{params}: {score:.5f}')
true_prev, estim_prev = qp.evaluation.artificial_sampling_prediction(model, dataset.test, SAMPLE_SIZE, n_prevpoints)
print(f'After model selection: Evaluation according to the artificial sampling protocol ({len(true_prev)} evals)')
for error in qp.error.QUANTIFICATION_ERROR:
score = error(true_prev, estim_prev)
print(f'{error.__name__}={score:.5f}')