def test_cluster_threshold():
"""Expected error for threshold to similarity should be reasonable"""
n_tests = 50
dim = 15
expected_error = 0.20
tot_err = 0
for test in range(n_tests):
# Get some sets and their similarities
sets = (randset(), randset())
jsim = jaccard_sim(*sets)
# Find the threshold at which they cluster together
for threshold in range(1, 100, 5):
threshold = float(threshold) / 100
cluster = Cluster(dim, threshold)
cluster.add_set(sets[0])
cluster.add_set(sets[1])
if len(cluster.get_sets()) == 2:
tot_err += abs(jsim - threshold)
break
avg_err = float(tot_err) / n_tests
assert avg_err <= expected_error
def test_cluster_threshold():
"""Expected error for threshold to similarity should be reasonable"""
n_tests = 50
dim = 15
expected_error = 0.20
tot_err = 0
for test in range(n_tests):
# Get some sets and their similarities
sets = (randset(), randset())
jsim = jaccard_sim(*sets)
# Find the threshold at which they cluster together
for threshold in range(1, 100, 5):
threshold = float(threshold) / 100
cluster = Cluster(dim, threshold)
cluster.add_set(sets[0])
cluster.add_set(sets[1])
if len(cluster.get_sets()) == 2:
tot_err += abs(jsim - threshold)
break
avg_err = float(tot_err) / n_tests
assert avg_err <= expected_error
def test_signature_similarity():
"""The probability that two sets' signatures match at some index
are equal is equal to the Jaccard similarity between the two"""
dim = 100
n_tests = 100
expected_error = 1 / sqrt(dim) # Expected error is O(1/sqrt(dim))
mh = MinHashSignature(dim)
err = 0.0
for test in range(n_tests):
# Create random sets and their signatures
sets = (randset(), randset())
sigs = map(mh.sign, sets)
# Calculate true jaccard similarity, and sim of signatures
jsim = jaccard_sim(*sets)
ssim = sigsim(*sigs, dim=dim)
# Accumulate error
err += abs(jsim - ssim)
# Over n_tests large, we should be within upper bound of expected error.
avg_err = err / n_tests
assert expected_error >= avg_err, "Accuracy test failed. (avg error: %f)" % avg_err
def test_signature_similarity():
"""The probability that two sets' signatures match at some index
are equal is equal to the Jaccard similarity between the two"""
dim = 100
n_tests = 100
expected_error = 1 / sqrt(dim) # Expected error is O(1/sqrt(dim))
mh = MinHashSignature(dim)
err = 0.0
for test in range(n_tests):
# Create random sets and their signatures
sets = (randset(), randset())
sigs = map(mh.sign, sets)
# Calculate true jaccard similarity, and sim of signatures
jsim = jaccard_sim(*sets)
ssim = sigsim(*sigs, dim=dim)
# Accumulate error
err += abs(jsim - ssim)
# Over n_tests large, we should be within upper bound of expected error.
avg_err = err / n_tests
assert expected_error >= avg_err, "Accuracy test failed. (avg error: %f)" % avg_err