Skip to content

Commit

Permalink
ENH : improvements in bayes
Browse files Browse the repository at this point in the history
  • Loading branch information
agramfort committed Sep 29, 2010
1 parent a5703a1 commit a07e818
Show file tree
Hide file tree
Showing 5 changed files with 228 additions and 321 deletions.
33 changes: 15 additions & 18 deletions examples/glm/plot_ard.py
@@ -1,50 +1,47 @@
"""
==================================================
Automatic Relevance Determination Regression
Automatic Relevance Determination Regression (ARD)
==================================================
Fit regression model with ARD
"""
print __doc__

from scikits.learn.glm import ARDRegression
import numpy as np
import pylab as pl
import numpy.random as nr
import scipy.stats as st
from scipy import stats

from scikits.learn.glm import ARDRegression

################################################################################
# Generating simulated data with Gaussian weigthts

### Parameters of the example
nr.seed(0)
n_samples = 50
n_features = 100
np.random.seed(0)
n_samples, n_features = 50, 100
### Create gaussian data
X = nr.randn(n_samples, n_features)
X = np.random.randn(n_samples, n_features)
### Create weigts with a precision lambda_ of 4.
lambda_ = 4.
w = np.zeros(n_features)
### Only keep 10 weights of interest
relevant_features = nr.randint(0,n_features,10)
relevant_features = np.random.randint(0, n_features, 10)
for i in relevant_features:
w[i] = st.norm.rvs(loc = 0, scale = 1./np.sqrt(lambda_))
w[i] = stats.norm.rvs(loc=0, scale=1. / np.sqrt(lambda_))
### Create noite with a precision alpha of 50.
alpha_ = 50.
noise = st.norm.rvs(loc = 0, scale = 1./np.sqrt(alpha_), size = n_samples)
noise = stats.norm.rvs(loc=0, scale=1. / np.sqrt(alpha_), size=n_samples)
### Create the target
Y = np.dot(X, w) + noise

y = np.dot(X, w) + noise

################################################################################
### Fit the ARD Regression
clf = ARDRegression(compute_score = True)
clf.fit(X, Y)


clf.fit(X, y)

################################################################################
### Plot the true weights, the estimated weights and the histogram of the
### weights

pl.figure()
axe = pl.axes([0.1,0.6,0.8,0.325])
axe.set_title("ARD - Weights of the model")
Expand All @@ -65,7 +62,7 @@

axe = pl.axes([0.65,0.1,0.3,0.325])
axe.set_title("Objective function")
axe.plot(clf.all_score_)
axe.plot(clf.scores_)
axe.set_ylabel("Score")
axe.set_xlabel("Iterations")
pl.show()
Expand Down
10 changes: 5 additions & 5 deletions examples/glm/plot_bayesian_ridge.py
Expand Up @@ -29,12 +29,12 @@
alpha_ = 50.
noise = stats.norm.rvs(loc = 0, scale = 1./np.sqrt(alpha_), size = n_samples)
# Create the target
Y = np.dot(X, w) + noise
y = np.dot(X, w) + noise

################################################################################
# Fit the Bayesian Ridge Regression
clf = BayesianRidge(compute_score=True)
clf.fit(X, Y)
clf.fit(X, y)

################################################################################
# Plot true weights, estimated weights and histogram of the weights
Expand All @@ -45,7 +45,7 @@
axe.plot(w, 'g-', label="Ground truth")
axe.set_xlabel("Features")
axe.set_ylabel("Values of the weights")
axe.legend(loc=1)
axe.legend(loc="upper right")

axe = pl.axes([0.1,0.1,0.45,0.325])
axe.set_title("Histogram of the weights")
Expand All @@ -54,11 +54,11 @@
label="Relevant features")
axe.set_ylabel("Features")
axe.set_xlabel("Values of the weights")
axe.legend(loc=1)
axe.legend(loc="lower left")

axe = pl.axes([0.65,0.1,0.3,0.325])
axe.set_title("Objective function")
axe.plot(clf.all_score_)
axe.plot(clf.scores_)
axe.set_ylabel("Score")
axe.set_xlabel("Iterations")
pl.show()
Expand Down

0 comments on commit a07e818

Please sign in to comment.