def test_gibbs_sbm(seed=None):
"""
Create a discrete time Hawkes model and generate from it.
:return:
"""
if seed is None:
seed = np.random.randint(2**32)
print "Setting seed to ", seed
np.random.seed(seed)
C = 10
K = 100
T = 1000
dt = 1.0
B = 3
# Generate from a true model
network_hypers = {'C': C, 'beta': 1.0 / K}
true_model = DiscreteTimeNetworkHawkesModelSpikeAndSlab(
K=K, dt=dt, B=B, network_hypers=network_hypers)
# S,R = true_model.generate(T=T)
c = true_model.network.c
perm = np.argsort(c)
# Plot the true network
plt.ion()
plot_network(true_model.weight_model.A[np.ix_(perm, perm)],
true_model.weight_model.W[np.ix_(perm, perm)])
plt.pause(0.001)
# Make a new model for inference
network_hypers = {'C': C, 'beta': 1.0 / K}
test_model = DiscreteTimeNetworkHawkesModelSpikeAndSlab(
K=K, dt=dt, B=B, network_hypers=network_hypers)
# test_model.add_data(S)
# Gibbs sample
N_samples = 10
samples = []
lps = []
for itr in xrange(N_samples):
if itr % 5 == 0:
print "Iteration: ", itr
samples.append(copy.deepcopy(test_model.get_parameters()))
lps.append(test_model.log_probability())
# Resample the network only
test_model.network.resample(
(true_model.weight_model.A, true_model.weight_model.W))
plt.ioff()
# Compute sample statistics for second half of samples
c_samples = np.array([c for _, _, _, _, c, _, _, _ in samples])
print "True c: ", true_model.network.c
print "Test c: ", c_samples[-10:, :]
# Compute the adjusted mutual info score of the clusterings
amis = []
arss = []
for c in c_samples:
amis.append(adjusted_mutual_info_score(true_model.network.c, c))
arss.append(adjusted_rand_score(true_model.network.c, c))
plt.figure()
plt.plot(np.arange(N_samples), amis, '-r')
plt.plot(np.arange(N_samples), arss, '-b')
plt.xlabel("Iteration")
plt.ylabel("Clustering score")
plt.show()
def fit_spikeslab_network_hawkes_gibbs(S, S_test, dt, dt_max, output_path,
model_args={}, standard_model=None,
N_samples=100, time_limit=8*60*60):
T,K = S.shape
# Check for existing Gibbs results
if os.path.exists(output_path):
with gzip.open(output_path, 'r') as f:
print "Loading Gibbs results from ", output_path
results = cPickle.load(f)
else:
print "Fitting the data with a network Hawkes model using Gibbs sampling"
test_model = DiscreteTimeNetworkHawkesModelSpikeAndSlab(K=K, dt=dt, dt_max=dt_max, **model_args)
test_model.add_data(S)
# Initialize with the standard model parameters
if standard_model is not None:
test_model.initialize_with_standard_model(standard_model)
# TODO: Precompute F_test
F_test = test_model.basis.convolve_with_basis(S_test)
# Gibbs sample
samples = []
lps = [test_model.log_probability()]
hlls = [test_model.heldout_log_likelihood(S_test)]
times = [0]
for _ in progprint_xrange(N_samples, perline=10):
# Update the model
tic = time.time()
test_model.resample_model()
samples.append(copy.deepcopy(test_model.get_parameters()))
times.append(time.time() - tic)
# Compute log probability and heldout log likelihood
# lps.append(test_model.log_probability())
hlls.append(test_model.heldout_log_likelihood(S_test, F=F_test))
# # Save this sample
# with open(output_path + ".gibbs.itr%04d.pkl" % itr, 'w') as f:
# cPickle.dump(samples[-1], f, protocol=-1)
# Check if time limit has been exceeded
if np.sum(times) > time_limit:
break
# Get cumulative timestamps
timestamps = np.cumsum(times)
lps = np.array(lps)
hlls = np.array(hlls)
# Make results object
results = Results(samples, timestamps, lps, hlls)
# Save the Gibbs samples
with gzip.open(output_path, 'w') as f:
print "Saving Gibbs samples to ", output_path
cPickle.dump(results, f, protocol=-1)
return results
def fit_spikeslab_network_hawkes_gibbs(S,
S_test,
dt,
dt_max,
output_path,
model_args={},
standard_model=None,
N_samples=100,
time_limit=8 * 60 * 60):
T, K = S.shape
# Check for existing Gibbs results
if os.path.exists(output_path):
with gzip.open(output_path, 'r') as f:
print("Loading Gibbs results from ", output_path)
results = pickle.load(f)
else:
print(
"Fitting the data with a network Hawkes model using Gibbs sampling"
)
test_model = DiscreteTimeNetworkHawkesModelSpikeAndSlab(K=K,
dt=dt,
dt_max=dt_max,
**model_args)
test_model.add_data(S)
# Initialize with the standard model parameters
if standard_model is not None:
test_model.initialize_with_standard_model(standard_model)
# TODO: Precompute F_test
F_test = test_model.basis.convolve_with_basis(S_test)
# Gibbs sample
samples = []
lps = [test_model.log_probability()]
hlls = [test_model.heldout_log_likelihood(S_test)]
times = [0]
for _ in progprint_xrange(N_samples, perline=10):
# Update the model
tic = time.time()
test_model.resample_model()
samples.append(copy.deepcopy(test_model.get_parameters()))
times.append(time.time() - tic)
# Compute log probability and heldout log likelihood
# lps.append(test_model.log_probability())
hlls.append(test_model.heldout_log_likelihood(S_test, F=F_test))
# # Save this sample
# with open(output_path + ".gibbs.itr%04d.pkl" % itr, 'w') as f:
# cPickle.dump(samples[-1], f, protocol=-1)
# Check if time limit has been exceeded
if np.sum(times) > time_limit:
break
# Get cumulative timestamps
timestamps = np.cumsum(times)
lps = np.array(lps)
hlls = np.array(hlls)
# Make results object
results = Results(samples, timestamps, lps, hlls)
# Save the Gibbs samples
with gzip.open(output_path, 'w') as f:
print("Saving Gibbs samples to ", output_path)
pickle.dump(results, f, protocol=-1)
return results
def test_gibbs_sbm(seed=None):
"""
Create a discrete time Hawkes model and generate from it.
:return:
"""
if seed is None:
seed = np.random.randint(2**32)
print "Setting seed to ", seed
np.random.seed(seed)
C = 10
K = 100
T = 1000
dt = 1.0
B = 3
# Generate from a true model
network_hypers = {'C': C, 'beta': 1.0/K}
true_model = DiscreteTimeNetworkHawkesModelSpikeAndSlab(K=K, dt=dt, B=B,
network_hypers=network_hypers)
# S,R = true_model.generate(T=T)
c = true_model.network.c
perm = np.argsort(c)
# Plot the true network
plt.ion()
plot_network(true_model.weight_model.A[np.ix_(perm, perm)],
true_model.weight_model.W[np.ix_(perm, perm)])
plt.pause(0.001)
# Make a new model for inference
network_hypers = {'C': C, 'beta': 1.0/K}
test_model = DiscreteTimeNetworkHawkesModelSpikeAndSlab(K=K, dt=dt, B=B,
network_hypers=network_hypers)
# test_model.add_data(S)
# Gibbs sample
N_samples = 10
samples = []
lps = []
for itr in xrange(N_samples):
if itr % 5 == 0:
print "Iteration: ", itr
samples.append(copy.deepcopy(test_model.get_parameters()))
lps.append(test_model.log_probability())
# Resample the network only
test_model.network.resample((true_model.weight_model.A,
true_model.weight_model.W))
plt.ioff()
# Compute sample statistics for second half of samples
c_samples = np.array([c for _,_,_,_,c,_,_,_ in samples])
print "True c: ", true_model.network.c
print "Test c: ", c_samples[-10:, :]
# Compute the adjusted mutual info score of the clusterings
amis = []
arss = []
for c in c_samples:
amis.append(adjusted_mutual_info_score(true_model.network.c, c))
arss.append(adjusted_rand_score(true_model.network.c, c))
plt.figure()
plt.plot(np.arange(N_samples), amis, '-r')
plt.plot(np.arange(N_samples), arss, '-b')
plt.xlabel("Iteration")
plt.ylabel("Clustering score")
plt.show()
