monitor_grid = Monitor()
for i in range(n_alphas):
log_alpha_i = np.log(alpha_max * p_alphas[:, i])
logit_multiclass.get_val(
model, X, y, log_alpha_i, None, monitor_grid, tol)
1/0
print("###################### GRAD SEARCH LS ###################")
n_outer = 100
model = SparseLogreg(estimator=estimator)
logit_multiclass = LogisticMulticlass(idx_train, idx_val, idx_test, algo)
monitor = Monitor()
log_alpha0 = np.ones(n_classes) * np.log(0.1 * alpha_max)
idx_min = np.argmin(np.array(monitor_grid.objs))
log_alpha0 = monitor_grid.log_alphas[idx_min]
optimizer = GradientDescent(
n_outer=n_outer, step_size=None, p_grad_norm=0.1, tol=tol)
grad_search(
algo, logit_multiclass, model, optimizer, X, y, log_alpha0, monitor)
print("###################### USE HYPEROPT ###################")
log_alpha_max = np.log(alpha_max)
log_alpha_min = np.log(alpha_max / 10_000)
monitor_hyp = Monitor()
hyperopt_wrapper(
algo, logit_multiclass, model, X, y, log_alpha_min, log_alpha_max,
monitor_hyp, tol=tol, size_space=n_classes, max_evals=10)
# all_algo_name = ['random_search']
for algo_name in all_algo_name:
model = ElasticNet(estimator=estimator)
sub_criterion = HeldOutMSE(None, None)
alpha0 = np.array([alpha_max / 10, alpha_max / 10])
monitor = Monitor()
kf = KFold(n_splits=5, shuffle=True, random_state=42)
criterion = CrossVal(sub_criterion, cv=kf)
algo = ImplicitForward(tol_jac=1e-3)
# optimizer = LineSearch(n_outer=10, tol=tol)
if algo_name.startswith('implicit_forward'):
if algo_name == "implicit_forward_approx":
optimizer = GradientDescent(n_outer=30,
p_grad_norm=1.,
verbose=True,
tol=tol,
tol_decrease="geom")
else:
optimizer = GradientDescent(n_outer=30,
p_grad_norm=1.,
verbose=True,
tol=tol)
grad_search(algo, criterion, model, optimizer, X, y, alpha0, monitor)
elif algo_name == 'grid_search':
grid_search(algo,
criterion,
model,
X,
y,
None,
def parallel_function(dataset_name,
method,
tol=1e-5,
n_outer=50,
tolerance_decrease='constant'):
# load data
X, y = fetch_libsvm(dataset_name)
y -= np.mean(y)
# compute alpha_max
alpha_max = np.abs(X.T @ y).max() / len(y)
if model_name == "logreg":
alpha_max /= 2
alpha_min = alpha_max * dict_palphamin[dataset_name]
if model_name == "enet":
estimator = linear_model.ElasticNet(fit_intercept=False,
max_iter=10_000,
warm_start=True,
tol=tol)
model = ElasticNet(estimator=estimator)
elif model_name == "logreg":
model = SparseLogreg(estimator=estimator)
# TODO improve this
try:
n_outer = dict_n_outers[dataset_name, method]
except Exception:
n_outer = 20
size_loop = 2
for _ in range(size_loop):
if model_name == "lasso" or model_name == "enet":
sub_criterion = HeldOutMSE(None, None)
elif model_name == "logreg":
criterion = HeldOutLogistic(None, None)
kf = KFold(n_splits=5, shuffle=True, random_state=42)
criterion = CrossVal(sub_criterion, cv=kf)
algo = ImplicitForward(tol_jac=1e-3)
monitor = Monitor()
t_max = dict_t_max[dataset_name]
if method == 'grid_search':
num1D = dict_point_grid_search[dataset_name]
alpha1D = np.geomspace(alpha_max, alpha_min, num=num1D)
alphas = [np.array(i) for i in product(alpha1D, alpha1D)]
grid_search(algo,
criterion,
model,
X,
y,
alpha_min,
alpha_max,
monitor,
max_evals=100,
tol=tol,
alphas=alphas)
elif method == 'random' or method == 'bayesian':
hyperopt_wrapper(algo,
criterion,
model,
X,
y,
alpha_min,
alpha_max,
monitor,
max_evals=30,
tol=tol,
method=method,
size_space=2,
t_max=t_max)
elif method.startswith("implicit_forward"):
# do gradient descent to find the optimal lambda
alpha0 = np.array([alpha_max / 100, alpha_max / 100])
n_outer = 30
if method == 'implicit_forward':
optimizer = GradientDescent(n_outer=n_outer,
p_grad_norm=1,
verbose=True,
tol=tol,
t_max=t_max)
else:
optimizer = GradientDescent(n_outer=n_outer,
p_grad_norm=1,
verbose=True,
tol=tol,
t_max=t_max,
tol_decrease="geom")
grad_search(algo, criterion, model, optimizer, X, y, alpha0,
monitor)
else:
raise NotImplementedError
monitor.times = np.array(monitor.times)
monitor.objs = np.array(monitor.objs)
monitor.objs_test = 0 # TODO
monitor.alphas = np.array(monitor.alphas)
return (dataset_name, method, tol, n_outer, tolerance_decrease,
monitor.times, monitor.objs, monitor.objs_test, monitor.alphas,
alpha_max, model_name)
print("Vanilla LassoCV: Mean-squared error on test data %f" % mse_cv)
##############################################################################
##############################################################################
# Weighted Lasso with sparse-ho.
# We use the vanilla lassoCV coefficients as a starting point
alpha0 = model_cv.alpha_ * np.ones(n_features)
# Weighted Lasso: Sparse-ho: 1 param per feature
estimator = Lasso(fit_intercept=False, max_iter=100, warm_start=True)
model = WeightedLasso(estimator=estimator)
sub_criterion = HeldOutMSE(idx_train, idx_val)
criterion = CrossVal(sub_criterion, cv=cv)
algo = ImplicitForward()
monitor = Monitor()
optimizer = GradientDescent(
n_outer=100, tol=1e-7, verbose=True, p_grad_norm=1.9)
results = grad_search(
algo, criterion, model, optimizer, X, y, alpha0, monitor)
##############################################################################
estimator.weights = monitor.alphas[-1]
estimator.fit(X, y)
##############################################################################
# MSE on validation set
mse_sho_val = mean_squared_error(y, estimator.predict(X))
# MSE on test set, ie unseen data
mse_sho_test = mean_squared_error(y_test, estimator.predict(X_test))
# Oracle MSE
mse_oracle = mean_squared_error(y_test, X_test @ w_true)
X,
y,
alpha_min,
alpha_max,
monitor_grid,
alphas=alphas,
tol=tol)
objs = np.array(monitor_grid.objs)
##############################################################################
# Grad-search
# -----------
optimizer_names = ['line-search', 'gradient-descent', 'adam']
optimizers = {
'line-search': LineSearch(n_outer=10, tol=tol),
'gradient-descent': GradientDescent(n_outer=10, step_size=100),
'adam': Adam(n_outer=10, lr=0.11)
}
monitors = {}
alpha0 = alpha_max / 10 # starting point
for optimizer_name in optimizer_names:
estimator = LogisticRegression(penalty='l1',
fit_intercept=False,
solver='saga',
tol=tol)
model = SparseLogreg(estimator=estimator)
criterion = HeldOutLogistic(idx_train, idx_val)
monitor_grad = Monitor()
##############################################################################
# Grad-search with sparse-ho
# --------------------------
estimator = linear_model.ElasticNet(fit_intercept=False,
max_iter=max_iter,
warm_start=True)
print("Started grad-search")
t_grad_search = -time.time()
monitor = Monitor()
n_outer = 10
alpha0 = np.array([alpha_max * 0.9, alpha_max * 0.9])
model = ElasticNet(estimator=estimator)
criterion = HeldOutMSE(idx_train, idx_val)
algo = ImplicitForward(tol_jac=1e-3, n_iter_jac=100, max_iter=max_iter)
optimizer = GradientDescent(n_outer=n_outer,
tol=tol,
p_grad_norm=1.5,
verbose=True)
grad_search(algo,
criterion,
model,
optimizer,
X,
y,
alpha0=alpha0,
monitor=monitor)
t_grad_search += time.time()
monitor.alphas = np.array(monitor.alphas)
print("Time grid search %f" % t_grid_search)
print("Time grad-search %f" % t_grad_search)
print("Minimum grid search %0.3e" % results.min())
# Grad-search
# -----------
print('sparse-ho started')
t0 = time.time()
estimator = LogisticRegression(
penalty='l1', fit_intercept=False, tol=tol)
model = SparseLogreg(estimator=estimator)
criterion = HeldOutLogistic(idx_train, idx_val)
monitor_grad = Monitor()
algo = ImplicitForward(tol_jac=tol, n_iter_jac=1000)
optimizer = GradientDescent(n_outer=10, tol=tol)
grad_search(
algo, criterion, model, optimizer, X, y, alpha0,
monitor_grad)
objs_grad = np.array(monitor_grad.objs)
t_grad_search = time.time() - t0
print('sparse-ho finished')
print(f"Time to compute grad search: {t_grad_search:.2f} s")
p_alphas_grad = np.array(monitor_grad.alphas) / alpha_max
objs_grad = np.array(monitor_grad.objs)
print("Starting path computation...")
for algorithm in algorithms:
estimator = celer.Lasso(fit_intercept=False,
max_iter=1000,
warm_start=True,
tol=tol)
print('%s started' % algorithm)
model = Lasso(estimator=estimator)
criterion = HeldOutMSE(None, None)
log_alpha0 = np.log(alpha_max / 10)
monitor = Monitor()
cross_val_criterion = CrossVal(criterion, cv=kf)
algo = ImplicitForward()
optimizer = GradientDescent(n_outer=10, tol=tol, verbose=True, p_grad0=1)
# optimizer = LineSearch(n_outer=10, tol=tol, verbose=True)
if algorithm == 'grad_search':
grad_search(algo, cross_val_criterion, model, optimizer, X, y,
log_alpha0, monitor)
objs = np.array(monitor.objs)
log_alphas = np.array(monitor.log_alphas)
elif algorithm.startswith('grid_search'):
if algorithm == 'grid_search10':
n_alphas = 10
else:
n_alphas = 100
p_alphas = np.geomspace(1, p_alpha_min, n_alphas)
alphas = alpha_max * p_alphas
reg = LassoCV(cv=kf,
tol=tol)
dict_monitor = {}
all_algo_name = ['implicit_forward', 'grid_search']
for algo_name in all_algo_name:
model = Lasso(estimator=estimator)
sub_criterion = HeldOutMSE(None, None)
alpha0 = alpha_max / 10
monitor = Monitor()
kf = KFold(n_splits=5, shuffle=True, random_state=42)
criterion = CrossVal(sub_criterion, cv=kf)
algo = ImplicitForward(tol_jac=1e-3)
optimizer = GradientDescent(n_outer=30,
p_grad_norm=1.,
verbose=True,
tol=tol)
if algo_name == 'implicit_forward':
grad_search(algo, criterion, model, optimizer, X, y, alpha0, monitor)
elif algo_name == 'grid_search':
grid_search(algo,
criterion,
model,
X,
y,
alpha_min,
alpha_max,
monitor,
max_evals=20,
tol=tol)
elif algo_name == 'random_search':
for algorithm in algorithms:
estimator = sklearn.linear_model.ElasticNet(
fit_intercept=False, max_iter=3_000, warm_start=True, tol=tol)
print('%s started' % algorithm)
model = ElasticNet(estimator=estimator)
criterion = HeldOutMSE(None, None)
log_alpha0 = np.array([np.log(alpha_max / 10), np.log(alpha_max / 10)])
monitor = Monitor()
cross_val_criterion = CrossVal(criterion, cv=kf)
algo = ImplicitForward()
# optimizer = LineSearch(n_outer=10, tol=tol, verbose=True)
if algorithm.startswith('grad_search'):
if algorithm == 'grad_search':
optimizer = GradientDescent(
n_outer=max_evals, tol=tol, verbose=True, p_grad_norm=1.9)
else:
optimizer = LineSearch(n_outer=25, verbose=True, tol=tol)
grad_search(
algo, cross_val_criterion, model, optimizer, X, y, log_alpha0,
monitor)
elif algorithm.startswith('grid_search'):
if algorithm == 'grid_search10':
n_alphas = 5
else:
n_alphas = 30
p_alphas = np.geomspace(1, p_alpha_min, n_alphas)
alphas = alpha_max * p_alphas
log_alphas = np.log(alphas)
grid_alphas = [i for i in itertools.product(log_alphas, log_alphas)]