first_monday(2016) + i * timedelta(weeks=1),
first_monday(2016) + (i + 4) * timedelta(weeks=1),
)
t_test2, y_test2 = get_data(
first_monday(2016) + (i + 4) * timedelta(weeks=1),
first_monday(2016) + (i + 5) * timedelta(weeks=1),
)
# Count since beginning of conditioning window. This assumes stationarity.
t_test2 -= t_test1[0]
t_test1 -= t_test1[0]
tests.append(((t_test1, y_test1), (t_test2, y_test2)))
# Save the data sets.
wd.save(
{
"t_train": t_train,
"y_train": y_train,
"tests": tests
},
"data.pickle",
)
# Setup GPCM models.
window = 7 * 6
scale = 5
n_u = 60
n_z = 150
noise = 0.05
# Normalise.
normaliser = Normaliser()
y_train = normaliser.transform(y_train)
return ks, us, fs
t = np.linspace(0, 10, 300)
noise_f = np.random.randn(len(t), 1)
# Construct model.
model = CGPCM(window=2, scale=1, n_u=10, t=t)
# Instantiate model.
models = model()
# Perform sampling.
if args.train:
ks, us, fs = sample(model, t, noise_f)
wd.save((ks, us, fs), "samples.pickle")
else:
ks, us, fs = wd.load("samples.pickle")
# Plot.
plt.figure(figsize=(15, 4))
for i, (k, u, f) in enumerate(zip(ks, us, fs)):
plt.subplot(3, 5, 1 + i)
plt.plot(
B.concat(-t[::-1][:-1], t),
B.concat(u[:-1] * 0, u),
lw=1,
)
if hasattr(model, "t_u"):
plt.scatter(model.t_u, model.t_u * 0, s=5, marker="o", c="black")
B.concat(samples[::-1, :][:-1, :], samples, axis=0),
)
# Perform sampling.
if args.train:
ks = [
_extract_samples(model.predict_kernel(num_samples=20000))
for model in models
]
psds = [
_extract_samples(model.predict_psd(num_samples=20000))
for model in models
]
model_ks, model_psds = ks, psds
wd.save((model_ks, model_psds), "samples.pickle")
else:
model_ks, model_psds = wd.load("samples.pickle")
# Plot.
plt.figure(figsize=(15, 2.5))
for i, (model, (x, ks)) in enumerate(zip(models, model_ks)):
plt.subplot(1, 6, 1 + i)
for q in [1, 5, 10, 20, 30, 40]:
plt.fill_between(
x,
B.quantile(ks, q / 100, axis=1),
B.quantile(ks, 1 - q / 100, axis=1),
facecolor="tab:blue",
alpha=0.2,
m_max=n_z // 2,
t=t,
),
),
]:
# Sample data.
gp_f = GP(kernel)
gp_y = gp_f + GP(noise * Delta(), measure=gp_f.measure)
f, y = gp_f.measure.sample(gp_f(t), gp_y(t))
f, y = B.flatten(f), B.flatten(y)
wd.save(
{
"t": t,
"f": f,
"k": B.flatten(kernel(t_k, 0)),
"y": y,
"true_logpdf": gp_y(t).logpdf(y),
},
slugify(str(kernel)),
"data.pickle",
)
for scheme in ["mean-field", "structured"]:
model = model_constructor(scheme)
prefix = (slugify(str(kernel)), scheme, slugify(model.name))
# Fit model and predict function and kernel.
model.fit(t, y, iters=10_000)
elbo = model.elbo(t, y)
posterior = model.condition(t, y)
f_pred = posterior.predict(t)
# Make and save predictions.
if args.predict:
posterior = model.condition(t, y)
pred_f = (t, ) + posterior.predict(t)
pred_psd = posterior.predict_psd()
pred_psd = (
pred_psd.x,
pred_psd.mean,
pred_psd.err_95_lower,
pred_psd.err_95_upper,
pred_psd.all_samples,
)
pred_k = posterior.predict_kernel()
pred_k = (pred_k.x, pred_k.mean, pred_k.var)
wd.save(pred_f, "pred_f.pickle")
wd.save(pred_psd, "pred_psd.pickle")
wd.save(pred_k, "pred_k.pickle")
else:
pred_f = wd.load("pred_f.pickle")
pred_psd = wd.load("pred_psd.pickle")
pred_k = wd.load("pred_k.pickle")
# Unpack prediction for the PDF and cut off a frequency 0.5.
freqs, mean, lower, upper, samps = pred_psd
upper_freq = 0.5
samps = samps[freqs <= upper_freq, :]
mean = mean[freqs <= upper_freq]
lower = lower[freqs <= upper_freq]
upper = upper[freqs <= upper_freq]
freqs = freqs[freqs <= upper_freq]
[sim.to_numpy()[:args.n].reshape(-1, 1) for sim in sims.values()],
axis=1)
corr_empirical = cov_to_corr(np.cov(all_obs.T))
# Compute predictions for latent processes.
model = construct_model(vs)
model = model.condition(x_data, y_data, x_ind=vs["x_ind"])
x_proj, y_proj, _, _ = model.project(x_data, y_data)
means, lowers, uppers = model.model.predict(x_proj)
# Save for processing.
wd.save(
B.to_numpy({
"n": args.n,
"m": m,
"p": p,
"m_r": m_r,
"m_s": m_s,
"x_proj": x_proj,
"y_proj": y_proj,
"means": means,
"lowers": lowers,
"uppers": uppers,
"learned_parameters": {name: vs[name]
for name in vs.names},
"corr_learned": corr_learned,
"corr_empirical": corr_empirical,
}),
f"results_mr{m_r}_ms{m_s}{suffix}.pickle",
)
d_all, d_train, d_tests = load_temp()[d_size]
# Determine the number of inducing points.
n_ind = [10 * 10 + 1, 10 * 15 + 1, 10 * 31 + 1][d_size]
# Place inducing points evenly spaced.
x = convert_index(d_all)
x_ind = np.linspace(x.min(), x.max(), n_ind)
# Fit and predict GPAR.
# Note: we use D-GPAR-L-NL here, as opposed to D-GPAR-L, to make the
# results a little more drastic.
model = GPARRegressor(scale=0.2,
linear=True, linear_scale=10.,
nonlinear=True, nonlinear_scale=1.,
noise=0.1,
impute=True, replace=True, normalise_y=True,
x_ind=x_ind)
model.fit(convert_index(d_train), d_train.to_numpy())
# Predict for the test sets.
preds = []
for i, d in enumerate(d_tests):
preds.append(model.predict(convert_index(d),
num_samples=50,
credible_bounds=True,
latent=False))
# Save predictions.
wd.save(preds, f'results{d_size}.pickle')
# Split data.
test_inds = np.empty(t.shape, dtype=bool)
test_inds.fill(False)
for lower, upper in [(
datetime(args.year, 1, 1) + i * timedelta(weeks=1),
datetime(args.year, 1, 1) + (i + 1) * timedelta(weeks=1),
) for i in range(26, 53) if i % 2 == 1]:
lower_mask = lower <= data.index
upper_mask = upper > data.index
test_inds = test_inds | (lower_mask & upper_mask)
t_train = t[~test_inds]
y_train = y[~test_inds]
t_test = t[test_inds]
y_test = y[test_inds]
# Save data for easier later reference.
wd.save({"train": (t_train, y_train), "test": (t_test, y_test)}, "data.pickle")
# Normalise training data.
normaliser = Normaliser()
y_train = normaliser.transform(y_train)
# Configure GPCM models.
window = 30
scale = 5
n_u = 50
n_z = 150
# Setup, fit, and save models.
models = [
Model(
window=window,
x = convert_index(d_all)
x_ind = np.linspace(x.min(), x.max(), n_ind)
# Fit and predict GPAR. NOTE: we use D-GPAR-L-NL here, as opposed to D-GPAR-L,
# to make the results a little more drastic.
model = GPARRegressor(
scale=0.2,
linear=True,
linear_scale=10.0,
nonlinear=True,
nonlinear_scale=1.0,
noise=0.1,
impute=True,
replace=True,
normalise_y=True,
x_ind=x_ind,
)
model.fit(convert_index(d_train), d_train.to_numpy())
# Predict for the test sets.
preds = []
for i, d in enumerate(d_tests):
preds.append(
model.predict(
convert_index(d), num_samples=50, credible_bounds=True, latent=False
)
)
# Save predictions.
wd.save(preds, f"results{d_size}.pickle")
# Train structured approximation.
model = GPCM(
scheme="structured",
window=window,
scale=scale,
noise=noise,
n_u=n_u,
n_z=n_z,
t=t,
)
model.fit(t, y, iters=30_000)
k_pred_struc = extract(model.condition(t, y).predict_kernel(t_k))
psd_pred_struc = extract(model.condition(t, y).predict_psd())
wd.save((k_pred_mf, psd_pred_mf, k_pred_struc, psd_pred_struc),
"preds.pickle")
else:
k_pred_mf, psd_pred_mf, k_pred_struc, psd_pred_struc = wd.load(
"preds.pickle")
# Report metrics.
with out.Section("Structured"):
t, mean, var, _, _ = k_pred_struc
inds = t <= 3
out.kv("MLL", metric.mll(mean[inds], var[inds], k[inds]))
out.kv("RMSE", metric.rmse(mean[inds], k[inds]))
with out.Section("Mean field"):
t, mean, var, _, _ = k_pred_mf
inds = t <= 3
out.kv("MLL", metric.mll(mean[inds], var[inds], k[inds]))
