def fit_gp_multinomial_model(model, test, pi_train=None, N_samples=100, run=1):
if pi_train is not None:
if isinstance(model, pgmult.gp.LogisticNormalGP):
model.data_list[0]["psi"] = ln_pi_to_psi(pi_train) - model.mu
elif isinstance(model, pgmult.gp.MultinomialGP):
model.data_list[0]["psi"] = pi_to_psi(pi_train) - model.mu
model.resample_omega()
else:
model.initialize_from_data()
### Inference
results_base = os.path.join("results", "names", "run%03d" % run, "results")
results_file = results_base + ".pkl.gz"
if os.path.exists(results_file):
with gzip.open(results_file, "r") as f:
samples, lls, pred_lls, timestamps = pickle.load(f)
else:
Z_test = get_inputs(test)
lls = [model.log_likelihood()]
samples = [model.copy_sample()]
pred_ll, pred_pi = model.predictive_log_likelihood(Z_test, test.data)
pred_lls = [pred_ll]
pred_pis = [pred_pi]
times = [0]
# Print initial values
print("Initial LL: ", lls[0])
print("Initial Pred LL: ", pred_lls[0])
for itr in xrange(N_samples):
print("Iteration ", itr)
tic = time.time()
model.resample_model(verbose=True)
times.append(time.time()-tic)
samples.append(model.copy_sample())
lls.append(model.log_likelihood())
pred_ll, pred_pi = model.predictive_log_likelihood(get_inputs(test), test.data)
pred_lls.append(pred_ll)
pred_pis.append(pred_pi)
print("Log likelihood: ", lls[-1])
print("Pred Log likelihood: ", pred_ll)
# Save this sample
# with gzip.open(results_file + ".itr%03d.pkl.gz" % itr, "w") as f:
# pickle.dump(model, f, protocol=-1)
lls = np.array(lls)
pred_lls = np.array(pred_lls)
timestamps = np.cumsum(times)
return samples, lls, pred_lls, pred_pis, timestamps
def fit_lds_model_with_pmcmc(Xs, Xtest, D, N_samples=100):
"""
Fit a logistic normal LDS model with pMCMC
"""
Nx = len(Xs)
assert len(Xtest) == Nx
print("Fitting SBM-LDS with %d states using pMCMC" % D)
models = [ParticleSBMultinomialLDS(
init_dynamics_distn=GaussianFixed(mu=np.zeros(D), sigma=1*np.eye(D)),
dynamics_distn=AutoRegression(nu_0=D+1,S_0=D*np.eye(D),M_0=np.zeros((D,D)),K_0=D*np.eye(D)),
emission_distn=Regression(nu_0=K+1,S_0=K*np.eye(K),M_0=np.zeros((K,D)),K_0=K*np.eye(D)),
mu=pi_to_psi(np.ones(K)/K),
sigma_C=1.0)
for _ in xrange(Nx)]
for model in models:
model.A = 0.5*np.eye(D)
model.sigma_states = np.eye(D)
model.C = np.random.randn(K-1,D)
model.sigma_obs = 0.1*np.eye(K)
for X, model in zip(Xs, models):
model.add_data(X)
def compute_pred_ll():
pred_ll = 0
for Xte, model in zip(Xtest, models):
pred_ll += model.predictive_log_likelihood(Xte, Npred=100)[0]
return pred_ll
init_results = (0, None, np.nan, np.nan, compute_pred_ll())
def resample():
tic = time.time()
[model.resample_model() for model in models]
toc = time.time() - tic
return toc, None, np.nan, np.nan, compute_pred_ll()
times, samples, lls, test_lls, pred_lls = \
map(np.array, zip(*([init_results] +
[resample() for _ in progprint_xrange(N_samples, perline=5)])))
timestamps = np.cumsum(times)
return Results(lls, test_lls, pred_lls, samples, timestamps)
def fit_lds_model_with_pmcmc(Xs, Xtest, D, N_samples=100):
"""
Fit a logistic normal LDS model with pMCMC
"""
print("Fitting SBM-LDS with %d states using pMCMC" % D)
model = ParticleSBMultinomialLDS(
init_dynamics_distn=GaussianFixed(mu=np.zeros(D), sigma=1*np.eye(D)),
dynamics_distn=AutoRegression(nu_0=D+1,S_0=D*np.eye(D),M_0=np.zeros((D,D)),K_0=D*np.eye(D)),
emission_distn=Regression(nu_0=K+1,S_0=K*np.eye(K),M_0=np.zeros((K,D)),K_0=K*np.eye(D)),
mu=pi_to_psi(np.ones(K)/K), sigma_C=0.01)
model.A = 0.5*np.eye(D)
model.sigma_states = np.eye(D)
model.C = 0.01 * np.random.randn(K-1,D)
model.sigma_obs = 0.1*np.eye(K)
for X in Xs:
model.add_data(X)
init_results = (0, None, model.log_likelihood(),
np.nan, model.predictive_log_likelihood(Xtest, Npred=1000))
def resample():
tic = time.time()
model.resample_model()
toc = time.time() - tic
pred_ll = model.predictive_log_likelihood(Xtest, Npred=1000)
return toc, None, model.log_likelihood(), \
np.nan, \
pred_ll
times, samples, lls, test_lls, pred_lls = \
map(np.array, zip(*([init_results] + [resample() for _ in progprint_xrange(N_samples)])))
timestamps = np.cumsum(times)
return Results(lls, test_lls, pred_lls, samples, timestamps)
nonempty_docs = np.asarray(model.data.sum(1) > 0).ravel()
model.theta[nonempty_docs] = ln_psi_to_pi(lmbda)
model.resample_z()
return model
fit_lda_gibbs = sampler_fitter(
'fit_lda_gibbs', StandardLDA, 'resample', lda_initializer)
fit_lda_collapsed = sampler_fitter(
'fit_lda_collapsed', StandardLDA, 'resample_collapsed', lda_initializer)
fit_lnctm_gibbs = sampler_fitter(
'fit_lnctm_gibbs', LogisticNormalCorrelatedLDA, 'resample',
make_ctm_initializer(lambda lmbda: lmbda))
fit_sbctm_gibbs = sampler_fitter(
'fit_sbctm_gibbs', StickbreakingCorrelatedLDA, 'resample',
make_ctm_initializer(lambda lmbda: pi_to_psi(ln_psi_to_pi(lmbda))))
########################
# inspecting results #
########################
def plot_sb_interpretable_results(sb_results, words):
nwords = 5
Sigma = sb_results[-1][-1]
T = Sigma.shape[0]
def get_topwords(topic):
return words[np.argsort(sb_results[-1][0][:,topic])[-nwords:]]
lim = np.abs(Sigma).max()
def theta(self, theta):
self.psi = pi_to_psi(theta)
