trying optimizing both prev and band at the same time, and per-class bandwidth
This commit is contained in:
parent
9fb208fe4c
commit
5f9dad4644
|
@ -0,0 +1,3 @@
|
|||
[submodule "result_table"]
|
||||
path = result_table
|
||||
url = gitea@gitea-s2i2s.isti.cnr.it:moreo/result_table.git
|
|
@ -0,0 +1,2 @@
|
|||
|
||||
DEBUG = False
|
|
@ -5,13 +5,14 @@ import numpy as np
|
|||
from sklearn.linear_model import LogisticRegression
|
||||
from os.path import join
|
||||
import quapy as qp
|
||||
from quapy.method.aggregative import KDEyML
|
||||
from quapy.protocol import UPP
|
||||
from kdey_devel import KDEyML
|
||||
from utils import measuretime
|
||||
from kdey_devel import KDEyMLauto
|
||||
from utils import *
|
||||
from constants import *
|
||||
import quapy.functional as F
|
||||
|
||||
|
||||
DEBUG = True
|
||||
|
||||
qp.environ["SAMPLE_SIZE"] = 100 if DEBUG else 500
|
||||
val_repeats = 100 if DEBUG else 500
|
||||
test_repeats = 100 if DEBUG else 500
|
||||
|
@ -27,7 +28,7 @@ if DEBUG:
|
|||
|
||||
|
||||
def datasets():
|
||||
dataset_list = qp.datasets.UCI_MULTICLASS_DATASETS
|
||||
dataset_list = qp.datasets.UCI_MULTICLASS_DATASETS[:4]
|
||||
if DEBUG:
|
||||
dataset_list = dataset_list[:4]
|
||||
for dataset_name in dataset_list:
|
||||
|
@ -58,11 +59,21 @@ def predict_b_modsel(dataset):
|
|||
# kdey.qua
|
||||
return modsel_choice
|
||||
|
||||
@measuretime
|
||||
def predict_b_kdeymlauto(dataset):
|
||||
# bandwidth chosen during model selection in validation
|
||||
train, test = dataset.train_test
|
||||
kdey = KDEyMLauto(random_state=0)
|
||||
print(f'true-prevalence: {F.strprev(test.prevalence())}')
|
||||
chosen_bandwidth, _ = kdey.chose_bandwidth(train, test.X)
|
||||
auto_bandwidth = float(chosen_bandwidth)
|
||||
return auto_bandwidth
|
||||
|
||||
|
||||
def in_test_search(dataset, n_jobs=-1):
|
||||
train, test = dataset.train_test
|
||||
|
||||
print(f"testing KDEy in {dataset.name}")
|
||||
print(f"generating true tests scores using KDEy in {dataset.name}")
|
||||
|
||||
def experiment_job(bandwidth):
|
||||
kdey = KDEyML(bandwidth=bandwidth, random_state=0)
|
||||
|
@ -76,50 +87,8 @@ def in_test_search(dataset, n_jobs=-1):
|
|||
return dataset_results, bandwidth_range
|
||||
|
||||
|
||||
def plot_bandwidth(dataset_name, test_results, bandwidths, triplet_list_results):
|
||||
import matplotlib.pyplot as plt
|
||||
|
||||
print("PLOT", dataset_name)
|
||||
print(dataset_name)
|
||||
|
||||
plt.figure(figsize=(8, 6))
|
||||
|
||||
# show test results
|
||||
plt.plot(bandwidths, test_results, marker='o')
|
||||
|
||||
for (method_name, method_choice, method_time) in triplet_list_results:
|
||||
plt.axvline(x=method_choice, linestyle='--', label=method_name)
|
||||
|
||||
# Agregar etiquetas y título
|
||||
plt.xlabel('Bandwidth')
|
||||
plt.ylabel('MAE')
|
||||
plt.title(dataset_name)
|
||||
|
||||
# Mostrar la leyenda
|
||||
plt.legend(loc='center left', bbox_to_anchor=(1, 0.5))
|
||||
|
||||
# Mostrar la gráfica
|
||||
plt.grid(True)
|
||||
|
||||
plotdir = './plots'
|
||||
if DEBUG:
|
||||
plotdir = './plots_debug'
|
||||
os.makedirs(plotdir, exist_ok=True)
|
||||
plt.tight_layout()
|
||||
plt.savefig(f'{plotdir}/{dataset_name}.png')
|
||||
plt.close()
|
||||
|
||||
def error_table(dataset_name, test_results, bandwidth_range, triplet_list_results):
|
||||
best_bandwidth = bandwidth_range[np.argmin(test_results)]
|
||||
print(f'Method\tChoice\tAE\tTime')
|
||||
for method_name, method_choice, took in triplet_list_results:
|
||||
if method_choice in bandwidth_range:
|
||||
index = np.where(bandwidth_range == method_choice)[0][0]
|
||||
method_score = test_results[index]
|
||||
else:
|
||||
method_score = 1
|
||||
error = np.abs(best_bandwidth-method_score)
|
||||
print(f'{method_name}\t{method_choice}\t{error}\t{took:.3}s')
|
||||
|
||||
|
||||
for dataset in datasets():
|
||||
|
@ -138,6 +107,8 @@ for dataset in datasets():
|
|||
triplet_list_results = []
|
||||
modsel_choice, modsel_time = qp.util.pickled_resource(join(result_path, 'modsel.pkl'), predict_b_modsel, dataset)
|
||||
triplet_list_results.append(('modsel', modsel_choice, modsel_time,))
|
||||
auto_choice, auto_time = qp.util.pickled_resource(join(result_path, 'auto.pkl'), predict_b_kdeymlauto, dataset)
|
||||
triplet_list_results.append(('auto', auto_choice, auto_time,))
|
||||
|
||||
print(f'Dataset = {dataset.name}')
|
||||
print(modsel_choice)
|
||||
|
|
|
@ -1,358 +1,171 @@
|
|||
from typing import Union
|
||||
from typing import Union, Callable
|
||||
import numpy as np
|
||||
from sklearn.base import BaseEstimator
|
||||
from sklearn.neighbors import KernelDensity
|
||||
|
||||
import quapy as qp
|
||||
from quapy.data import LabelledCollection
|
||||
from quapy.method.aggregative import AggregativeSoftQuantifier
|
||||
from quapy.method.aggregative import AggregativeSoftQuantifier, KDEyML
|
||||
import quapy.functional as F
|
||||
|
||||
from sklearn.metrics.pairwise import rbf_kernel
|
||||
from scipy import optimize
|
||||
|
||||
|
||||
class KDEBase:
|
||||
"""
|
||||
Common ancestor for KDE-based methods. Implements some common routines.
|
||||
"""
|
||||
|
||||
BANDWIDTH_METHOD = ['scott', 'silverman']
|
||||
|
||||
@classmethod
|
||||
def _check_bandwidth(cls, bandwidth):
|
||||
"""
|
||||
Checks that the bandwidth parameter is correct
|
||||
|
||||
:param bandwidth: either a string (see BANDWIDTH_METHOD) or a float
|
||||
:return: the bandwidth if the check is passed, or raises an exception for invalid values
|
||||
"""
|
||||
assert bandwidth in KDEBase.BANDWIDTH_METHOD or isinstance(bandwidth, float), \
|
||||
f'invalid bandwidth, valid ones are {KDEBase.BANDWIDTH_METHOD} or float values'
|
||||
if isinstance(bandwidth, float):
|
||||
assert 0 < bandwidth < 1, \
|
||||
"the bandwith for KDEy should be in (0,1), since this method models the unit simplex"
|
||||
return bandwidth
|
||||
|
||||
def get_kde_function(self, X, bandwidth):
|
||||
"""
|
||||
Wraps the KDE function from scikit-learn.
|
||||
|
||||
:param X: data for which the density function is to be estimated
|
||||
:param bandwidth: the bandwidth of the kernel
|
||||
:return: a scikit-learn's KernelDensity object
|
||||
"""
|
||||
return KernelDensity(bandwidth=bandwidth).fit(X)
|
||||
|
||||
def pdf(self, kde, X):
|
||||
"""
|
||||
Wraps the density evalution of scikit-learn's KDE. Scikit-learn returns log-scores (s), so this
|
||||
function returns :math:`e^{s}`
|
||||
|
||||
:param kde: a previously fit KDE function
|
||||
:param X: the data for which the density is to be estimated
|
||||
:return: np.ndarray with the densities
|
||||
"""
|
||||
return np.exp(kde.score_samples(X))
|
||||
|
||||
def get_mixture_components(self, X, y, classes, bandwidth):
|
||||
"""
|
||||
Returns an array containing the mixture components, i.e., the KDE functions for each class.
|
||||
|
||||
:param X: the data containing the covariates
|
||||
:param y: the class labels
|
||||
:param n_classes: integer, the number of classes
|
||||
:param bandwidth: float, the bandwidth of the kernel
|
||||
:return: a list of KernelDensity objects, each fitted with the corresponding class-specific covariates
|
||||
"""
|
||||
class_cond_X = []
|
||||
for cat in classes:
|
||||
selX = X[y == cat]
|
||||
if selX.size == 0:
|
||||
selX = [F.uniform_prevalence(len(classes))]
|
||||
class_cond_X.append(selX)
|
||||
return [self.get_kde_function(X_cond_yi, bandwidth) for X_cond_yi in class_cond_X]
|
||||
|
||||
|
||||
class KDEyML(AggregativeSoftQuantifier, KDEBase):
|
||||
"""
|
||||
Kernel Density Estimation model for quantification (KDEy) relying on the Kullback-Leibler divergence (KLD) as
|
||||
the divergence measure to be minimized. This method was first proposed in the paper
|
||||
`Kernel Density Estimation for Multiclass Quantification <https://arxiv.org/abs/2401.00490>`_, in which
|
||||
the authors show that minimizing the distribution mathing criterion for KLD is akin to performing
|
||||
maximum likelihood (ML).
|
||||
|
||||
The distribution matching optimization problem comes down to solving:
|
||||
|
||||
:math:`\\hat{\\alpha} = \\arg\\min_{\\alpha\\in\\Delta^{n-1}} \\mathcal{D}(\\boldsymbol{p}_{\\alpha}||q_{\\widetilde{U}})`
|
||||
|
||||
where :math:`p_{\\alpha}` is the mixture of class-specific KDEs with mixture parameter (hence class prevalence)
|
||||
:math:`\\alpha` defined by
|
||||
|
||||
:math:`\\boldsymbol{p}_{\\alpha}(\\widetilde{x}) = \\sum_{i=1}^n \\alpha_i p_{\\widetilde{L}_i}(\\widetilde{x})`
|
||||
|
||||
where :math:`p_X(\\boldsymbol{x}) = \\frac{1}{|X|} \\sum_{x_i\\in X} K\\left(\\frac{x-x_i}{h}\\right)` is the
|
||||
KDE function that uses the datapoints in X as the kernel centers.
|
||||
|
||||
In KDEy-ML, the divergence is taken to be the Kullback-Leibler Divergence. This is equivalent to solving:
|
||||
:math:`\\hat{\\alpha} = \\arg\\min_{\\alpha\\in\\Delta^{n-1}} -
|
||||
\\mathbb{E}_{q_{\\widetilde{U}}} \\left[ \\log \\boldsymbol{p}_{\\alpha}(\\widetilde{x}) \\right]`
|
||||
|
||||
which corresponds to the maximum likelihood estimate.
|
||||
|
||||
:param classifier: a sklearn's Estimator that generates a binary classifier.
|
||||
:param val_split: specifies the data used for generating classifier predictions. This specification
|
||||
can be made as float in (0, 1) indicating the proportion of stratified held-out validation set to
|
||||
be extracted from the training set; or as an integer (default 5), indicating that the predictions
|
||||
are to be generated in a `k`-fold cross-validation manner (with this integer indicating the value
|
||||
for `k`); or as a collection defining the specific set of data to use for validation.
|
||||
Alternatively, this set can be specified at fit time by indicating the exact set of data
|
||||
on which the predictions are to be generated.
|
||||
:param bandwidth: float, the bandwidth of the Kernel
|
||||
:param random_state: a seed to be set before fitting any base quantifier (default None)
|
||||
"""
|
||||
|
||||
def __init__(self, classifier: BaseEstimator = None, val_split=5, bandwidth=0.1, random_state=None):
|
||||
class KDEyMLauto(KDEyML):
|
||||
def __init__(self, classifier: BaseEstimator = None, val_split=5, random_state=None, optim='two_steps'):
|
||||
self.classifier = qp._get_classifier(classifier)
|
||||
self.val_split = val_split
|
||||
self.bandwidth = KDEBase._check_bandwidth(bandwidth)
|
||||
self.bandwidth = None
|
||||
self.random_state = random_state
|
||||
self.optim = optim
|
||||
|
||||
def aggregation_fit(self, classif_predictions: LabelledCollection, data: LabelledCollection):
|
||||
self.mix_densities = self.get_mixture_components(*classif_predictions.Xy, data.classes_, self.bandwidth)
|
||||
return self
|
||||
def chose_bandwidth(self, train, test_instances):
|
||||
classif_predictions = self.classifier_fit_predict(train, fit_classifier=True, predict_on=self.val_split)
|
||||
te_posteriors = self.classify(test_instances)
|
||||
return self.transduce(classif_predictions, te_posteriors)
|
||||
|
||||
def aggregate(self, posteriors: np.ndarray):
|
||||
"""
|
||||
Searches for the mixture model parameter (the sought prevalence values) that maximizes the likelihood
|
||||
of the data (i.e., that minimizes the negative log-likelihood)
|
||||
def transduce(self, classif_predictions, te_posteriors):
|
||||
tr_posteriors, tr_y = classif_predictions.Xy
|
||||
classes = classif_predictions.classes_
|
||||
n_classes = len(classes)
|
||||
|
||||
:param posteriors: instances in the sample converted into posterior probabilities
|
||||
:return: a vector of class prevalence estimates
|
||||
"""
|
||||
current_bandwidth = 0.05
|
||||
if self.optim == 'both_fine':
|
||||
current_bandwidth = np.full(fill_value=current_bandwidth, shape=(n_classes,))
|
||||
current_prevalence = np.full(fill_value=1 / n_classes, shape=(n_classes,))
|
||||
|
||||
iterations = 0
|
||||
convergence = False
|
||||
with qp.util.temp_seed(self.random_state):
|
||||
epsilon = 1e-10
|
||||
n_classes = len(self.mix_densities)
|
||||
test_densities = [self.pdf(kde_i, posteriors) for kde_i in self.mix_densities]
|
||||
|
||||
def neg_loglikelihood(prev):
|
||||
test_mixture_likelihood = sum(prev_i * dens_i for prev_i, dens_i in zip(prev, test_densities))
|
||||
test_loglikelihood = np.log(test_mixture_likelihood + epsilon)
|
||||
return -np.sum(test_loglikelihood)
|
||||
while not convergence:
|
||||
previous_bandwidth = current_bandwidth
|
||||
previous_prevalence = current_prevalence
|
||||
|
||||
return F.optim_minimize(neg_loglikelihood, n_classes)
|
||||
iterations += 1
|
||||
print(f'{iterations}:')
|
||||
|
||||
if self.optim == 'two_steps':
|
||||
current_prevalence = self.optim_minimize_prevalence(current_bandwidth, current_prevalence, tr_posteriors, tr_y, te_posteriors, classes)
|
||||
print(f'\testim-prev={F.strprev(current_prevalence)}')
|
||||
|
||||
class KDEyHD(AggregativeSoftQuantifier, KDEBase):
|
||||
"""
|
||||
Kernel Density Estimation model for quantification (KDEy) relying on the squared Hellinger Disntace (HD) as
|
||||
the divergence measure to be minimized. This method was first proposed in the paper
|
||||
`Kernel Density Estimation for Multiclass Quantification <https://arxiv.org/abs/2401.00490>`_, in which
|
||||
the authors proposed a Monte Carlo approach for minimizing the divergence.
|
||||
current_bandwidth = self.optim_minimize_bandwidth(current_bandwidth, current_prevalence, tr_posteriors, tr_y, te_posteriors, classes)
|
||||
print(f'\tbandwidth={current_bandwidth}')
|
||||
if np.isclose(previous_bandwidth, current_bandwidth, atol=0.0001) and all(
|
||||
np.isclose(previous_prevalence, current_prevalence, atol=0.0001)):
|
||||
convergence = True
|
||||
elif self.optim == 'both':
|
||||
current_prevalence, current_bandwidth = self.optim_minimize_both(current_bandwidth, current_prevalence, tr_posteriors, tr_y, te_posteriors, classes)
|
||||
if np.isclose(previous_bandwidth, current_bandwidth, atol=0.0001) and all(np.isclose(previous_prevalence, current_prevalence, atol=0.0001)):
|
||||
convergence = True
|
||||
elif self.optim == 'both_fine':
|
||||
current_prevalence, current_bandwidth = self.optim_minimize_both_fine(current_bandwidth, current_prevalence, tr_posteriors, tr_y,
|
||||
te_posteriors, classes)
|
||||
|
||||
The distribution matching optimization problem comes down to solving:
|
||||
if all(np.isclose(previous_bandwidth, current_bandwidth, atol=0.0001)) and all(np.isclose(previous_prevalence, current_prevalence, atol=0.0001)):
|
||||
convergence = True
|
||||
|
||||
:math:`\\hat{\\alpha} = \\arg\\min_{\\alpha\\in\\Delta^{n-1}} \\mathcal{D}(\\boldsymbol{p}_{\\alpha}||q_{\\widetilde{U}})`
|
||||
|
||||
where :math:`p_{\\alpha}` is the mixture of class-specific KDEs with mixture parameter (hence class prevalence)
|
||||
:math:`\\alpha` defined by
|
||||
|
||||
:math:`\\boldsymbol{p}_{\\alpha}(\\widetilde{x}) = \\sum_{i=1}^n \\alpha_i p_{\\widetilde{L}_i}(\\widetilde{x})`
|
||||
|
||||
where :math:`p_X(\\boldsymbol{x}) = \\frac{1}{|X|} \\sum_{x_i\\in X} K\\left(\\frac{x-x_i}{h}\\right)` is the
|
||||
KDE function that uses the datapoints in X as the kernel centers.
|
||||
|
||||
In KDEy-HD, the divergence is taken to be the squared Hellinger Distance, an f-divergence with corresponding
|
||||
f-generator function given by:
|
||||
|
||||
:math:`f(u)=(\\sqrt{u}-1)^2`
|
||||
|
||||
The authors proposed a Monte Carlo solution that relies on importance sampling:
|
||||
|
||||
:math:`\\hat{D}_f(p||q)= \\frac{1}{t} \\sum_{i=1}^t f\\left(\\frac{p(x_i)}{q(x_i)}\\right) \\frac{q(x_i)}{r(x_i)}`
|
||||
|
||||
where the datapoints (trials) :math:`x_1,\\ldots,x_t\\sim_{\\mathrm{iid}} r` with :math:`r` the
|
||||
uniform distribution.
|
||||
|
||||
:param classifier: a sklearn's Estimator that generates a binary classifier.
|
||||
:param val_split: specifies the data used for generating classifier predictions. This specification
|
||||
can be made as float in (0, 1) indicating the proportion of stratified held-out validation set to
|
||||
be extracted from the training set; or as an integer (default 5), indicating that the predictions
|
||||
are to be generated in a `k`-fold cross-validation manner (with this integer indicating the value
|
||||
for `k`); or as a collection defining the specific set of data to use for validation.
|
||||
Alternatively, this set can be specified at fit time by indicating the exact set of data
|
||||
on which the predictions are to be generated.
|
||||
:param bandwidth: float, the bandwidth of the Kernel
|
||||
:param random_state: a seed to be set before fitting any base quantifier (default None)
|
||||
:param montecarlo_trials: number of Monte Carlo trials (default 10000)
|
||||
"""
|
||||
|
||||
def __init__(self, classifier: BaseEstimator = None, val_split=5, divergence: str = 'HD',
|
||||
bandwidth=0.1, random_state=None, montecarlo_trials=10000):
|
||||
|
||||
self.classifier = qp._get_classifier(classifier)
|
||||
self.val_split = val_split
|
||||
self.divergence = divergence
|
||||
self.bandwidth = KDEBase._check_bandwidth(bandwidth)
|
||||
self.random_state = random_state
|
||||
self.montecarlo_trials = montecarlo_trials
|
||||
|
||||
def aggregation_fit(self, classif_predictions: LabelledCollection, data: LabelledCollection):
|
||||
self.mix_densities = self.get_mixture_components(*classif_predictions.Xy, data.classes_, self.bandwidth)
|
||||
|
||||
N = self.montecarlo_trials
|
||||
rs = self.random_state
|
||||
n = data.n_classes
|
||||
self.reference_samples = np.vstack([kde_i.sample(N // n, random_state=rs) for kde_i in self.mix_densities])
|
||||
self.reference_classwise_densities = np.asarray(
|
||||
[self.pdf(kde_j, self.reference_samples) for kde_j in self.mix_densities])
|
||||
self.reference_density = np.mean(self.reference_classwise_densities,
|
||||
axis=0) # equiv. to (uniform @ self.reference_classwise_densities)
|
||||
|
||||
return self
|
||||
|
||||
def aggregate(self, posteriors: np.ndarray):
|
||||
# we retain all n*N examples (sampled from a mixture with uniform parameter), and then
|
||||
# apply importance sampling (IS). In this version we compute D(p_alpha||q) with IS
|
||||
n_classes = len(self.mix_densities)
|
||||
|
||||
test_kde = self.get_kde_function(posteriors, self.bandwidth)
|
||||
test_densities = self.pdf(test_kde, self.reference_samples)
|
||||
|
||||
def f_squared_hellinger(u):
|
||||
return (np.sqrt(u) - 1) ** 2
|
||||
|
||||
# todo: this will fail when self.divergence is a callable, and is not the right place to do it anyway
|
||||
if self.divergence.lower() == 'hd':
|
||||
f = f_squared_hellinger
|
||||
else:
|
||||
raise ValueError('only squared HD is currently implemented')
|
||||
self.bandwidth = current_bandwidth
|
||||
print('bandwidth=', current_bandwidth)
|
||||
print('prevalence=', current_prevalence)
|
||||
return current_prevalence
|
||||
|
||||
def optim_minimize_prevalence(self, current_bandwidth, current_prev, tr_posteriors, tr_y, te_posteriors, classes):
|
||||
epsilon = 1e-10
|
||||
qs = test_densities + epsilon
|
||||
rs = self.reference_density + epsilon
|
||||
iw = qs / rs # importance weights
|
||||
p_class = self.reference_classwise_densities + epsilon
|
||||
fracs = p_class / qs
|
||||
mix_densities = self.get_mixture_components(tr_posteriors, tr_y, classes, current_bandwidth)
|
||||
test_densities = [self.pdf(kde_i, te_posteriors) for kde_i in mix_densities]
|
||||
|
||||
def divergence(prev):
|
||||
# ps / qs = (prev @ p_class) / qs = prev @ (p_class / qs) = prev @ fracs
|
||||
ps_div_qs = prev @ fracs
|
||||
return np.mean(f(ps_div_qs) * iw)
|
||||
def neg_loglikelihood_prev(prev):
|
||||
test_mixture_likelihood = sum(prev_i * dens_i for prev_i, dens_i in zip(prev, test_densities))
|
||||
test_loglikelihood = np.log(test_mixture_likelihood + epsilon)
|
||||
return -np.sum(test_loglikelihood)
|
||||
|
||||
return F.optim_minimize(divergence, n_classes)
|
||||
return optim_minimize(neg_loglikelihood_prev, current_prev)
|
||||
|
||||
def optim_minimize_bandwidth(self, current_bandwidth, current_prev, tr_posteriors, tr_y, te_posteriors, classes):
|
||||
epsilon = 1e-10
|
||||
def neg_loglikelihood_bandwidth(bandwidth):
|
||||
mix_densities = self.get_mixture_components(tr_posteriors, tr_y, classes, bandwidth[0])
|
||||
test_densities = [self.pdf(kde_i, te_posteriors) for kde_i in mix_densities]
|
||||
test_mixture_likelihood = sum(prev_i * dens_i for prev_i, dens_i in zip(current_prev, test_densities))
|
||||
test_loglikelihood = np.log(test_mixture_likelihood + epsilon)
|
||||
return -np.sum(test_loglikelihood)
|
||||
|
||||
class KDEyCS(AggregativeSoftQuantifier):
|
||||
"""
|
||||
Kernel Density Estimation model for quantification (KDEy) relying on the Cauchy-Schwarz divergence (CS) as
|
||||
the divergence measure to be minimized. This method was first proposed in the paper
|
||||
`Kernel Density Estimation for Multiclass Quantification <https://arxiv.org/abs/2401.00490>`_, in which
|
||||
the authors proposed a Monte Carlo approach for minimizing the divergence.
|
||||
bounds = [(0.00001, 1)]
|
||||
r = optimize.minimize(neg_loglikelihood_bandwidth, x0=[current_bandwidth], method='SLSQP', bounds=bounds)
|
||||
print(f'iterations-bandwidth={r.nit}')
|
||||
return r.x[0]
|
||||
|
||||
The distribution matching optimization problem comes down to solving:
|
||||
def optim_minimize_both(self, current_bandwidth, current_prev, tr_posteriors, tr_y, te_posteriors, classes):
|
||||
epsilon = 1e-10
|
||||
n_classes = len(current_prev)
|
||||
def neg_loglikelihood_bandwidth(prevalence_bandwidth):
|
||||
bandwidth = prevalence_bandwidth[-1]
|
||||
prevalence = prevalence_bandwidth[:-1]
|
||||
mix_densities = self.get_mixture_components(tr_posteriors, tr_y, classes, bandwidth)
|
||||
test_densities = [self.pdf(kde_i, te_posteriors) for kde_i in mix_densities]
|
||||
test_mixture_likelihood = sum(prev_i * dens_i for prev_i, dens_i in zip(prevalence, test_densities))
|
||||
test_loglikelihood = np.log(test_mixture_likelihood + epsilon)
|
||||
return -np.sum(test_loglikelihood)
|
||||
|
||||
:math:`\\hat{\\alpha} = \\arg\\min_{\\alpha\\in\\Delta^{n-1}} \\mathcal{D}(\\boldsymbol{p}_{\\alpha}||q_{\\widetilde{U}})`
|
||||
bounds = [(0, 1) for _ in range(n_classes)] + [(0.00001, 1)]
|
||||
constraints = ({'type': 'eq', 'fun': lambda x: 1 - sum(x[:n_classes])})
|
||||
prevalence_bandwidth = np.append(current_prev, current_bandwidth)
|
||||
r = optimize.minimize(neg_loglikelihood_bandwidth, x0=prevalence_bandwidth, method='SLSQP', bounds=bounds, constraints=constraints)
|
||||
print(f'iterations-both={r.nit}')
|
||||
prev_band = r.x
|
||||
current_prevalence = prev_band[:-1]
|
||||
current_bandwidth = prev_band[-1]
|
||||
return current_prevalence, current_bandwidth
|
||||
|
||||
where :math:`p_{\\alpha}` is the mixture of class-specific KDEs with mixture parameter (hence class prevalence)
|
||||
:math:`\\alpha` defined by
|
||||
def optim_minimize_both_fine(self, current_bandwidth, current_prev, tr_posteriors, tr_y, te_posteriors, classes):
|
||||
epsilon = 1e-10
|
||||
n_classes = len(current_bandwidth)
|
||||
def neg_loglikelihood_bandwidth(prevalence_bandwidth):
|
||||
prevalence = prevalence_bandwidth[:n_classes]
|
||||
bandwidth = prevalence_bandwidth[n_classes:]
|
||||
mix_densities = self.get_mixture_components(tr_posteriors, tr_y, classes, bandwidth)
|
||||
test_densities = [self.pdf(kde_i, te_posteriors) for kde_i in mix_densities]
|
||||
test_mixture_likelihood = sum(prev_i * dens_i for prev_i, dens_i in zip(prevalence, test_densities))
|
||||
test_loglikelihood = np.log(test_mixture_likelihood + epsilon)
|
||||
return -np.sum(test_loglikelihood)
|
||||
|
||||
:math:`\\boldsymbol{p}_{\\alpha}(\\widetilde{x}) = \\sum_{i=1}^n \\alpha_i p_{\\widetilde{L}_i}(\\widetilde{x})`
|
||||
|
||||
where :math:`p_X(\\boldsymbol{x}) = \\frac{1}{|X|} \\sum_{x_i\\in X} K\\left(\\frac{x-x_i}{h}\\right)` is the
|
||||
KDE function that uses the datapoints in X as the kernel centers.
|
||||
|
||||
In KDEy-CS, the divergence is taken to be the Cauchy-Schwarz divergence given by:
|
||||
|
||||
:math:`\\mathcal{D}_{\\mathrm{CS}}(p||q)=-\\log\\left(\\frac{\\int p(x)q(x)dx}{\\sqrt{\\int p(x)^2dx \\int q(x)^2dx}}\\right)`
|
||||
|
||||
The authors showed that this distribution matching admits a closed-form solution
|
||||
|
||||
:param classifier: a sklearn's Estimator that generates a binary classifier.
|
||||
:param val_split: specifies the data used for generating classifier predictions. This specification
|
||||
can be made as float in (0, 1) indicating the proportion of stratified held-out validation set to
|
||||
be extracted from the training set; or as an integer (default 5), indicating that the predictions
|
||||
are to be generated in a `k`-fold cross-validation manner (with this integer indicating the value
|
||||
for `k`); or as a collection defining the specific set of data to use for validation.
|
||||
Alternatively, this set can be specified at fit time by indicating the exact set of data
|
||||
on which the predictions are to be generated.
|
||||
:param bandwidth: float, the bandwidth of the Kernel
|
||||
"""
|
||||
|
||||
def __init__(self, classifier: BaseEstimator = None, val_split=5, bandwidth=0.1):
|
||||
self.classifier = qp._get_classifier(classifier)
|
||||
self.val_split = val_split
|
||||
self.bandwidth = KDEBase._check_bandwidth(bandwidth)
|
||||
|
||||
def gram_matrix_mix_sum(self, X, Y=None):
|
||||
# this adapts the output of the rbf_kernel function (pairwise evaluations of Gaussian kernels k(x,y))
|
||||
# to contain pairwise evaluations of N(x|mu,Sigma1+Sigma2) with mu=y and Sigma1 and Sigma2 are
|
||||
# two "scalar matrices" (h^2)*I each, so Sigma1+Sigma2 has scalar 2(h^2) (h is the bandwidth)
|
||||
h = self.bandwidth
|
||||
variance = 2 * (h ** 2)
|
||||
nD = X.shape[1]
|
||||
gamma = 1 / (2 * variance)
|
||||
norm_factor = 1 / np.sqrt(((2 * np.pi) ** nD) * (variance ** (nD)))
|
||||
gram = norm_factor * rbf_kernel(X, Y, gamma=gamma)
|
||||
return gram.sum()
|
||||
bounds = [(0, 1) for _ in range(n_classes)] + [(0.00001, 1) for _ in range(n_classes)]
|
||||
constraints = ({'type': 'eq', 'fun': lambda x: 1 - sum(x[:n_classes])})
|
||||
prevalence_bandwidth = np.concatenate((current_prev, current_bandwidth))
|
||||
r = optimize.minimize(neg_loglikelihood_bandwidth, x0=prevalence_bandwidth, method='SLSQP', bounds=bounds, constraints=constraints)
|
||||
print(f'iterations-both-fine={r.nit}')
|
||||
prev_band = r.x
|
||||
current_prevalence = prev_band[:n_classes]
|
||||
current_bandwidth = prev_band[n_classes:]
|
||||
return current_prevalence, current_bandwidth
|
||||
|
||||
def aggregation_fit(self, classif_predictions: LabelledCollection, data: LabelledCollection):
|
||||
|
||||
P, y = classif_predictions.Xy
|
||||
n = data.n_classes
|
||||
|
||||
assert all(sorted(np.unique(y)) == np.arange(n)), \
|
||||
'label name gaps not allowed in current implementation'
|
||||
|
||||
# counts_inv keeps track of the relative weight of each datapoint within its class
|
||||
# (i.e., the weight in its KDE model)
|
||||
counts_inv = 1 / (data.counts())
|
||||
|
||||
# tr_tr_sums corresponds to symbol \overline{B} in the paper
|
||||
tr_tr_sums = np.zeros(shape=(n, n), dtype=float)
|
||||
for i in range(n):
|
||||
for j in range(n):
|
||||
if i > j:
|
||||
tr_tr_sums[i, j] = tr_tr_sums[j, i]
|
||||
else:
|
||||
block = self.gram_matrix_mix_sum(P[y == i], P[y == j] if i != j else None)
|
||||
tr_tr_sums[i, j] = block
|
||||
|
||||
# keep track of these data structures for the test phase
|
||||
self.Ptr = P
|
||||
self.ytr = y
|
||||
self.tr_tr_sums = tr_tr_sums
|
||||
self.counts_inv = counts_inv
|
||||
|
||||
self.classif_predictions = classif_predictions
|
||||
return self
|
||||
|
||||
def aggregate(self, posteriors: np.ndarray):
|
||||
Ptr = self.Ptr
|
||||
Pte = posteriors
|
||||
y = self.ytr
|
||||
tr_tr_sums = self.tr_tr_sums
|
||||
return self.transduce(self.classif_predictions, posteriors)
|
||||
|
||||
M, nD = Pte.shape
|
||||
Minv = (1 / M) # t in the paper
|
||||
n = Ptr.shape[1]
|
||||
|
||||
# becomes a constant that does not affect the optimization, no need to compute it
|
||||
# partC = 0.5*np.log(self.gram_matrix_mix_sum(Pte) * Kinv * Kinv)
|
||||
def optim_minimize(loss: Callable, init_prev: np.ndarray):
|
||||
"""
|
||||
Searches for the optimal prevalence values, i.e., an `n_classes`-dimensional vector of the (`n_classes`-1)-simplex
|
||||
that yields the smallest lost. This optimization is carried out by means of a constrained search using scipy's
|
||||
SLSQP routine.
|
||||
|
||||
# tr_te_sums corresponds to \overline{a}*(1/Li)*(1/M) in the paper (note the constants
|
||||
# are already aggregated to tr_te_sums, so these multiplications are not carried out
|
||||
# at each iteration of the optimization phase)
|
||||
tr_te_sums = np.zeros(shape=n, dtype=float)
|
||||
for i in range(n):
|
||||
tr_te_sums[i] = self.gram_matrix_mix_sum(Ptr[y == i], Pte)
|
||||
:param loss: (callable) the function to minimize
|
||||
:return: (ndarray) the best prevalence vector found
|
||||
"""
|
||||
|
||||
def divergence(alpha):
|
||||
# called \overline{r} in the paper
|
||||
alpha_ratio = alpha * self.counts_inv
|
||||
|
||||
# recall that tr_te_sums already accounts for the constant terms (1/Li)*(1/M)
|
||||
partA = -np.log((alpha_ratio @ tr_te_sums) * Minv)
|
||||
partB = 0.5 * np.log(alpha_ratio @ tr_tr_sums @ alpha_ratio)
|
||||
return partA + partB # + partC
|
||||
|
||||
return F.optim_minimize(divergence, n)
|
||||
n_classes = len(init_prev)
|
||||
# solutions are bounded to those contained in the unit-simplex
|
||||
bounds = tuple((0, 1) for _ in range(n_classes)) # values in [0,1]
|
||||
constraints = ({'type': 'eq', 'fun': lambda x: 1 - sum(x)}) # values summing up to 1
|
||||
r = optimize.minimize(loss, x0=init_prev, method='SLSQP', bounds=bounds, constraints=constraints)
|
||||
print(f'iterations-prevalence={r.nit}')
|
||||
return r.x
|
||||
|
||||
|
|
|
@ -0,0 +1,156 @@
|
|||
import pickle
|
||||
import os
|
||||
from time import time
|
||||
from collections import defaultdict
|
||||
|
||||
import numpy as np
|
||||
from sklearn.linear_model import LogisticRegression
|
||||
|
||||
import quapy as qp
|
||||
from KDEy.kdey_devel import KDEyMLauto
|
||||
from quapy.method.aggregative import PACC, EMQ, KDEyML
|
||||
from quapy.model_selection import GridSearchQ
|
||||
from quapy.protocol import UPP
|
||||
from pathlib import Path
|
||||
|
||||
SEED = 1
|
||||
|
||||
|
||||
def newLR():
|
||||
return LogisticRegression(max_iter=3000)
|
||||
|
||||
|
||||
# typical hyperparameters explored for Logistic Regression
|
||||
logreg_grid = {
|
||||
'C': [1],
|
||||
'class_weight': [None]
|
||||
}
|
||||
|
||||
|
||||
def wrap_hyper(classifier_hyper_grid: dict):
|
||||
return {'classifier__' + k: v for k, v in classifier_hyper_grid.items()}
|
||||
|
||||
|
||||
METHODS = [
|
||||
('PACC', PACC(newLR()), wrap_hyper(logreg_grid)),
|
||||
('EMQ', EMQ(newLR()), wrap_hyper(logreg_grid)),
|
||||
('KDEy-ML', KDEyML(newLR()), {**wrap_hyper(logreg_grid), **{'bandwidth': np.linspace(0.01, 0.2, 20)}}),
|
||||
]
|
||||
|
||||
|
||||
"""
|
||||
TKDEyML era primero bandwidth (init 0.05) y luego prevalence (init uniform)
|
||||
TKDEyML2 era primero prevalence (init uniform) y luego bandwidth (init 0.05)
|
||||
TKDEyML3 era primero prevalence (init uniform) y luego bandwidth (init 0.1)
|
||||
TKDEyML4 es como ML2 pero max 5 iteraciones por optimización
|
||||
"""
|
||||
TRANSDUCTIVE_METHODS = [
|
||||
#('TKDEy-ML', KDEyMLauto(newLR()), None),
|
||||
('TKDEy-MLboth', KDEyMLauto(newLR(), optim='both'), None),
|
||||
('TKDEy-MLbothfine', KDEyMLauto(newLR(), optim='both_fine'), None),
|
||||
('TKDEy-ML2', KDEyMLauto(newLR()), None),
|
||||
#('TKDEy-ML3', KDEyMLauto(newLR()), None),
|
||||
#('TKDEy-ML4', KDEyMLauto(newLR()), None),
|
||||
]
|
||||
|
||||
def show_results(result_path):
|
||||
import pandas as pd
|
||||
df = pd.read_csv(result_path + '.csv', sep='\t')
|
||||
pd.set_option('display.max_columns', None)
|
||||
pd.set_option('display.max_rows', None)
|
||||
pv = df.pivot_table(index='Dataset', columns="Method", values=["MAE", "MRAE", "t_train"], margins=True)
|
||||
print(pv)
|
||||
|
||||
|
||||
def load_timings(result_path):
|
||||
import pandas as pd
|
||||
timings = defaultdict(lambda: {})
|
||||
if not Path(result_path + '.csv').exists():
|
||||
return timings
|
||||
|
||||
df = pd.read_csv(result_path + '.csv', sep='\t')
|
||||
return timings | df.pivot_table(index='Dataset', columns='Method', values='t_train').to_dict()
|
||||
|
||||
|
||||
if __name__ == '__main__':
|
||||
|
||||
qp.environ['SAMPLE_SIZE'] = 500
|
||||
qp.environ['N_JOBS'] = -1
|
||||
n_bags_val = 25
|
||||
n_bags_test = 100
|
||||
result_dir = f'results_quantification/ucimulti'
|
||||
|
||||
os.makedirs(result_dir, exist_ok=True)
|
||||
|
||||
global_result_path = f'{result_dir}/allmethods'
|
||||
timings = load_timings(global_result_path)
|
||||
with open(global_result_path + '.csv', 'wt') as csv:
|
||||
csv.write(f'Method\tDataset\tMAE\tMRAE\tt_train\n')
|
||||
|
||||
for method_name, quantifier, param_grid in METHODS + TRANSDUCTIVE_METHODS:
|
||||
|
||||
print('Init method', method_name)
|
||||
|
||||
with open(global_result_path + '.csv', 'at') as csv:
|
||||
for dataset in qp.datasets.UCI_MULTICLASS_DATASETS[:4]:
|
||||
print('init', dataset)
|
||||
|
||||
local_result_path = os.path.join(Path(global_result_path).parent,
|
||||
method_name + '_' + dataset + '.dataframe')
|
||||
|
||||
if os.path.exists(local_result_path):
|
||||
print(f'result file {local_result_path} already exist; skipping')
|
||||
report = qp.util.load_report(local_result_path)
|
||||
|
||||
else:
|
||||
with qp.util.temp_seed(SEED):
|
||||
|
||||
data = qp.datasets.fetch_UCIMulticlassDataset(dataset, verbose=True)
|
||||
|
||||
if not method_name.startswith("TKDEy-ML"):
|
||||
# model selection
|
||||
train, test = data.train_test
|
||||
train, val = train.split_stratified(random_state=SEED)
|
||||
|
||||
protocol = UPP(val, repeats=n_bags_val)
|
||||
modsel = GridSearchQ(
|
||||
quantifier, param_grid, protocol, refit=True, n_jobs=-1, verbose=1, error='mae'
|
||||
)
|
||||
|
||||
t_init = time()
|
||||
try:
|
||||
modsel.fit(train)
|
||||
|
||||
print(f'best params {modsel.best_params_}')
|
||||
print(f'best score {modsel.best_score_}')
|
||||
|
||||
quantifier = modsel.best_model()
|
||||
except:
|
||||
print('something went wrong... trying to fit the default model')
|
||||
quantifier.fit(train)
|
||||
timings[method_name][dataset] = time() - t_init
|
||||
|
||||
protocol = UPP(test, repeats=n_bags_test)
|
||||
report = qp.evaluation.evaluation_report(
|
||||
quantifier, protocol, error_metrics=['mae', 'mrae'], verbose=True
|
||||
)
|
||||
report.to_csv(local_result_path)
|
||||
else:
|
||||
# model selection
|
||||
train, test = data.train_test
|
||||
t_init = time()
|
||||
quantifier.fit(train)
|
||||
timings[method_name][dataset] = time() - t_init
|
||||
|
||||
protocol = UPP(test, repeats=n_bags_test)
|
||||
report = qp.evaluation.evaluation_report(
|
||||
quantifier, protocol, error_metrics=['mae', 'mrae'], verbose=True
|
||||
)
|
||||
report.to_csv(local_result_path)
|
||||
|
||||
means = report.mean(numeric_only=True)
|
||||
csv.write(
|
||||
f'{method_name}\t{dataset}\t{means["mae"]:.5f}\t{means["mrae"]:.5f}\n')#\t{timings[method_name][dataset]:.3f}\n')
|
||||
csv.flush()
|
||||
|
||||
show_results(global_result_path)
|
|
@ -1,5 +1,10 @@
|
|||
import time
|
||||
from functools import wraps
|
||||
import os
|
||||
from os.path import join
|
||||
from result_table.src.table import Table
|
||||
import numpy as np
|
||||
from constants import *
|
||||
|
||||
def measuretime(func):
|
||||
@wraps(func)
|
||||
|
@ -12,4 +17,65 @@ def measuretime(func):
|
|||
return (*result, time_it_took)
|
||||
else:
|
||||
return result, time_it_took
|
||||
return wrapper
|
||||
return wrapper
|
||||
|
||||
|
||||
def plot_bandwidth(dataset_name, test_results, bandwidths, triplet_list_results):
|
||||
import matplotlib.pyplot as plt
|
||||
|
||||
print("PLOT", dataset_name)
|
||||
print(dataset_name)
|
||||
|
||||
plt.figure(figsize=(8, 6))
|
||||
|
||||
# show test results
|
||||
plt.plot(bandwidths, test_results, marker='o', color='k')
|
||||
|
||||
colors = plt.cm.tab10(np.linspace(0, 1, len(triplet_list_results)))
|
||||
for i, (method_name, method_choice, method_time) in enumerate(triplet_list_results):
|
||||
plt.axvline(x=method_choice, linestyle='--', label=method_name, color=colors[i])
|
||||
|
||||
# Agregar etiquetas y título
|
||||
plt.xlabel('Bandwidth')
|
||||
plt.ylabel('MAE')
|
||||
plt.title(dataset_name)
|
||||
|
||||
# Mostrar la leyenda
|
||||
plt.legend(loc='center left', bbox_to_anchor=(1, 0.5))
|
||||
|
||||
# Mostrar la gráfica
|
||||
plt.grid(True)
|
||||
|
||||
plotdir = './plots'
|
||||
if DEBUG:
|
||||
plotdir = './plots_debug'
|
||||
os.makedirs(plotdir, exist_ok=True)
|
||||
plt.tight_layout()
|
||||
plt.savefig(f'{plotdir}/{dataset_name}.png')
|
||||
plt.close()
|
||||
|
||||
def error_table(dataset_name, test_results, bandwidth_range, triplet_list_results):
|
||||
best_bandwidth = bandwidth_range[np.argmin(test_results)]
|
||||
best_score = np.min(test_results)
|
||||
print(f'Method\tChoice\tAE\tTime')
|
||||
table=Table(name=dataset_name)
|
||||
table.format.with_mean=False
|
||||
table.format.with_rank_mean = False
|
||||
table.format.show_std = False
|
||||
for method_name, method_choice, took in triplet_list_results:
|
||||
if method_choice in bandwidth_range:
|
||||
index = np.where(bandwidth_range == method_choice)[0][0]
|
||||
method_score = test_results[index]
|
||||
else:
|
||||
method_score = 1
|
||||
error = np.abs(best_score-method_score)
|
||||
table.add(benchmark='Choice', method=method_name, v=method_choice)
|
||||
table.add(benchmark='ScoreChoice', method=method_name, v=method_score)
|
||||
table.add(benchmark='Best', method=method_name, v=best_bandwidth)
|
||||
table.add(benchmark='ScoreBest', method=method_name, v=best_score)
|
||||
table.add(benchmark='AE', method=method_name, v=error)
|
||||
table.add(benchmark='Time', method=method_name, v=took)
|
||||
outpath = './tables'
|
||||
if DEBUG:
|
||||
outpath = './tables_debug'
|
||||
table.latexPDF(join(outpath, dataset_name+'.pdf'), transpose=True)
|
|
@ -14,7 +14,7 @@ from . import model_selection
|
|||
from . import classification
|
||||
import os
|
||||
|
||||
__version__ = '0.1.9'
|
||||
__version__ = '0.1.10'
|
||||
|
||||
environ = {
|
||||
'SAMPLE_SIZE': None,
|
||||
|
|
|
@ -3,6 +3,7 @@ from contextlib import contextmanager
|
|||
import zipfile
|
||||
from os.path import join
|
||||
import pandas as pd
|
||||
import sklearn.datasets
|
||||
from ucimlrepo import fetch_ucirepo
|
||||
from quapy.data.base import Dataset, LabelledCollection
|
||||
from quapy.data.preprocessing import text2tfidf, reduce_columns
|
||||
|
@ -1004,3 +1005,49 @@ def fetch_IFCB(single_sample_train=True, for_model_selection=False, data_home=No
|
|||
return train, test_gen
|
||||
else:
|
||||
return train_gen, test_gen
|
||||
|
||||
|
||||
def syntheticUniformLabelledCollection(n_samples, n_features, n_classes, n_clusters_per_class=1, **kwargs):
|
||||
"""
|
||||
Generates a synthetic labelled collection with uniform priors and
|
||||
of `n_samples` instances, `n_features` features, and `n_classes` classes.
|
||||
The underlying generator relies on the function
|
||||
`sklearn.datasets.make_classification`. Other options can be specified using the `kwargs`;
|
||||
see the `scikit-learn documentation
|
||||
<https://scikit-learn.org/stable/modules/generated/sklearn.datasets.make_classification.html>`_
|
||||
for a full list of optional parameters.
|
||||
|
||||
:param n_samples: number of instances
|
||||
:param n_features: number of features
|
||||
:param n_classes: number of classes
|
||||
"""
|
||||
X, y = sklearn.datasets.make_classification(
|
||||
n_samples=n_samples,
|
||||
n_features=n_features,
|
||||
n_classes=n_classes,
|
||||
n_clusters_per_class=n_clusters_per_class,
|
||||
**kwargs
|
||||
)
|
||||
|
||||
return LabelledCollection(X, y)
|
||||
|
||||
def syntheticUniformDataset(n_samples, n_features, n_classes, test_split=0.3, **kwargs):
|
||||
"""
|
||||
Generates a synthetic Dataset with approximately uniform priors and
|
||||
of `n_samples` instances, `n_features` features, and `n_classes` classes.
|
||||
The underlying generator relies on the function
|
||||
`sklearn.datasets.make_classification`. Other options can be specified using the `kwargs`;
|
||||
see the `scikit-learn documentation
|
||||
<https://scikit-learn.org/stable/modules/generated/sklearn.datasets.make_classification.html>`_
|
||||
for a full list of optional parameters.
|
||||
|
||||
:param n_samples: number of instances
|
||||
:param n_features: number of features
|
||||
:param n_classes: number of classes
|
||||
:param test_split: proportion of test instances
|
||||
"""
|
||||
assert 0. < test_split < 1., "invalid proportion of test instances; the value must be in (0, 1)"
|
||||
lc = syntheticUniformLabelledCollection(n_samples, n_features, n_classes, **kwargs)
|
||||
training, test = lc.split_stratified(train_prop=1-test_split, random_state=kwargs.get('random_state', None))
|
||||
dataset = Dataset(training=training, test=test, name=f'synthetic(nF={n_features},nC={n_classes})')
|
||||
return dataset
|
|
@ -66,11 +66,13 @@ class KDEBase:
|
|||
"""
|
||||
class_cond_X = []
|
||||
for cat in classes:
|
||||
selX = X[y==cat]
|
||||
if selX.size==0:
|
||||
selX = X[y == cat]
|
||||
if selX.size == 0:
|
||||
selX = [F.uniform_prevalence(len(classes))]
|
||||
class_cond_X.append(selX)
|
||||
return [self.get_kde_function(X_cond_yi, bandwidth) for X_cond_yi in class_cond_X]
|
||||
if isinstance(bandwidth, float):
|
||||
bandwidth = np.full(fill_value=bandwidth, shape=(len(classes),))
|
||||
return [self.get_kde_function(X_cond_yi, band_i) for X_cond_yi, band_i in zip(class_cond_X, bandwidth)]
|
||||
|
||||
|
||||
class KDEyML(AggregativeSoftQuantifier, KDEBase):
|
||||
|
@ -188,7 +190,7 @@ class KDEyHD(AggregativeSoftQuantifier, KDEBase):
|
|||
|
||||
def __init__(self, classifier: BaseEstimator=None, val_split=5, divergence: str='HD',
|
||||
bandwidth=0.1, random_state=None, montecarlo_trials=10000):
|
||||
|
||||
|
||||
self.classifier = qp._get_classifier(classifier)
|
||||
self.val_split = val_split
|
||||
self.divergence = divergence
|
||||
|
@ -218,7 +220,7 @@ class KDEyHD(AggregativeSoftQuantifier, KDEBase):
|
|||
|
||||
def f_squared_hellinger(u):
|
||||
return (np.sqrt(u)-1)**2
|
||||
|
||||
|
||||
# todo: this will fail when self.divergence is a callable, and is not the right place to do it anyway
|
||||
if self.divergence.lower() == 'hd':
|
||||
f = f_squared_hellinger
|
||||
|
@ -283,7 +285,7 @@ class KDEyCS(AggregativeSoftQuantifier):
|
|||
|
||||
def gram_matrix_mix_sum(self, X, Y=None):
|
||||
# this adapts the output of the rbf_kernel function (pairwise evaluations of Gaussian kernels k(x,y))
|
||||
# to contain pairwise evaluations of N(x|mu,Sigma1+Sigma2) with mu=y and Sigma1 and Sigma2 are
|
||||
# to contain pairwise evaluations of N(x|mu,Sigma1+Sigma2) with mu=y and Sigma1 and Sigma2 are
|
||||
# two "scalar matrices" (h^2)*I each, so Sigma1+Sigma2 has scalar 2(h^2) (h is the bandwidth)
|
||||
h = self.bandwidth
|
||||
variance = 2 * (h**2)
|
||||
|
@ -342,7 +344,7 @@ class KDEyCS(AggregativeSoftQuantifier):
|
|||
# at each iteration of the optimization phase)
|
||||
tr_te_sums = np.zeros(shape=n, dtype=float)
|
||||
for i in range(n):
|
||||
tr_te_sums[i] = self.gram_matrix_mix_sum(Ptr[y==i], Pte)
|
||||
tr_te_sums[i] = self.gram_matrix_mix_sum(Ptr[y==i], Pte)
|
||||
|
||||
def divergence(alpha):
|
||||
# called \overline{r} in the paper
|
||||
|
|
|
@ -0,0 +1 @@
|
|||
Subproject commit c223c9f1fe3c9708e8c5a5c56e438cdaaa857be4
|
Loading…
Reference in New Issue