Operations on word vectors - v2
import numpy as np
from w2v_utils import *
words, word_to_vec_map = read_glove_vecs('data/glove.6B.50d.txt')
1 - Cosine similarity
# GRADED FUNCTION: cosine_similarity
def cosine_similarity(u, v):
"""
Cosine similarity reflects the degree of similariy between u and v
Arguments:
u -- a word vector of shape (n,)
v -- a word vector of shape (n,)
Returns:
cosine_similarity -- the cosine similarity between u and v defined by the formula above.
"""
distance = 0.0
### START CODE HERE ###
# Compute the dot product between u and v (≈1 line)
dot = np.dot(u,v)
# Compute the L2 norm of u (≈1 line)
norm_u = np.sqrt(np.sum(u*u))
# Compute the L2 norm of v (≈1 line)
norm_v = np.sqrt(np.sum(v*v))
# Compute the cosine similarity defined by formula (1) (≈1 line)
cosine_similarity = dot/(norm_u*norm_v)
### END CODE HERE ###
return cosine_similarityfather = word_to_vec_map["father"]
mother = word_to_vec_map["mother"]
ball = word_to_vec_map["ball"]
crocodile = word_to_vec_map["crocodile"]
france = word_to_vec_map["france"]
italy = word_to_vec_map["italy"]
paris = word_to_vec_map["paris"]
rome = word_to_vec_map["rome"]
print("cosine_similarity(father, mother) = ", cosine_similarity(father, mother))
print("cosine_similarity(ball, crocodile) = ",cosine_similarity(ball, crocodile))
print("cosine_similarity(france - paris, rome - italy) = ",cosine_similarity(france - paris, rome - italy))cosine_similarity(father, mother) = 0.890903844289
cosine_similarity(ball, crocodile) = 0.274392462614
cosine_similarity(france - paris, rome - italy) = -0.675147930817
2 - Word analogy task
# GRADED FUNCTION: complete_analogy
def complete_analogy(word_a, word_b, word_c, word_to_vec_map):
"""
Performs the word analogy task as explained above: a is to b as c is to ____.
Arguments:
word_a -- a word, string
word_b -- a word, string
word_c -- a word, string
word_to_vec_map -- dictionary that maps words to their corresponding vectors.
Returns:
best_word -- the word such that v_b - v_a is close to v_best_word - v_c, as measured by cosine similarity
"""
# convert words to lower case
word_a, word_b, word_c = word_a.lower(), word_b.lower(), word_c.lower()
### START CODE HERE ###
# Get the word embeddings v_a, v_b and v_c (≈1-3 lines)
e_a, e_b, e_c = word_to_vec_map[word_a],word_to_vec_map[word_b],word_to_vec_map[word_c]
### END CODE HERE ###
words = word_to_vec_map.keys()
max_cosine_sim = -100 # Initialize max_cosine_sim to a large negative number
best_word = None # Initialize best_word with None, it will help keep track of the word to output
# loop over the whole word vector set
for w in words:
# to avoid best_word being one of the input words, pass on them.
if w in [word_a, word_b, word_c] :
continue
### START CODE HERE ###
# Compute cosine similarity between the vector (e_b - e_a) and the vector ((w's vector representation) - e_c) (≈1 line)
cosine_sim = cosine_similarity(e_b-e_a,word_to_vec_map[w]-e_c)
# If the cosine_sim is more than the max_cosine_sim seen so far,
# then: set the new max_cosine_sim to the current cosine_sim and the best_word to the current word (≈3 lines)
if cosine_sim > max_cosine_sim:
max_cosine_sim = cosine_sim
best_word = w
### END CODE HERE ###
return best_wordtriads_to_try = [('italy', 'italian', 'spain'), ('india', 'delhi', 'japan'), ('man', 'woman', 'boy'), ('small', 'smaller', 'large')]
for triad in triads_to_try:
print ('{} -> {} :: {} -> {}'.format( *triad, complete_analogy(*triad,word_to_vec_map)))italy -> italian :: spain -> spanish
india -> delhi :: japan -> tokyo
man -> woman :: boy -> girl
small -> smaller :: large -> larger
3 - Debiasing word vectors (OPTIONAL/UNGRADED)
g = word_to_vec_map['woman'] - word_to_vec_map['man']
print(g)[-0.087144 0.2182 -0.40986 -0.03922 -0.1032 0.94165
-0.06042 0.32988 0.46144 -0.35962 0.31102 -0.86824
0.96006 0.01073 0.24337 0.08193 -1.02722 -0.21122
0.695044 -0.00222 0.29106 0.5053 -0.099454 0.40445
0.30181 0.1355 -0.0606 -0.07131 -0.19245 -0.06115
-0.3204 0.07165 -0.13337 -0.25068714 -0.14293 -0.224957
-0.149 0.048882 0.12191 -0.27362 -0.165476 -0.20426
0.54376 -0.271425 -0.10245 -0.32108 0.2516 -0.33455
-0.04371 0.01258 ]
print ('List of names and their similarities with constructed vector:')
# girls and boys name
name_list = ['john', 'marie', 'sophie', 'ronaldo', 'priya', 'rahul', 'danielle', 'reza', 'katy', 'yasmin']
for w in name_list:
print (w, cosine_similarity(word_to_vec_map[w], g))List of names and their similarities with constructed vector:
john -0.23163356146
marie 0.315597935396
sophie 0.318687898594
ronaldo -0.312447968503
priya 0.17632041839
rahul -0.169154710392
danielle 0.243932992163
reza -0.079304296722
katy 0.283106865957
yasmin 0.233138577679
print('Other words and their similarities:')
word_list = ['lipstick', 'guns', 'science', 'arts', 'literature', 'warrior','doctor', 'tree', 'receptionist',
'technology', 'fashion', 'teacher', 'engineer', 'pilot', 'computer', 'singer']
for w in word_list:
print (w, cosine_similarity(word_to_vec_map[w], g))Other words and their similarities:
lipstick 0.276919162564
guns -0.18884855679
science -0.0608290654093
arts 0.00818931238588
literature 0.0647250443346
warrior -0.209201646411
doctor 0.118952894109
tree -0.0708939917548
receptionist 0.330779417506
technology -0.131937324476
fashion 0.0356389462577
teacher 0.179209234318
engineer -0.0803928049452
pilot 0.00107644989919
computer -0.103303588739
singer 0.1850051813653.1 - Neutralize bias for non-gender specific words
def neutralize(word, g, word_to_vec_map):
"""
Removes the bias of "word" by projecting it on the space orthogonal to the bias axis.
This function ensures that gender neutral words are zero in the gender subspace.
Arguments:
word -- string indicating the word to debias
g -- numpy-array of shape (50,), corresponding to the bias axis (such as gender)
word_to_vec_map -- dictionary mapping words to their corresponding vectors.
Returns:
e_debiased -- neutralized word vector representation of the input "word"
"""
### START CODE HERE ###
# Select word vector representation of "word". Use word_to_vec_map. (≈ 1 line)
e = word_to_vec_map[w]
# Compute e_biascomponent using the formula give above. (≈ 1 line)
e_biascomponent = np.dot(e,g)/np.sum(g*g)*g
# Neutralize e by substracting e_biascomponent from it
# e_debiased should be equal to its orthogonal projection. (≈ 1 line)
e_debiased = e-e_biascomponent
### END CODE HERE ###
return e_debiasede = "receptionist"
print("cosine similarity between " + e + " and g, before neutralizing: ", cosine_similarity(word_to_vec_map["receptionist"], g))
e_debiased = neutralize("receptionist", g, word_to_vec_map)
print("cosine similarity between " + e + " and g, after neutralizing: ", cosine_similarity(e_debiased, g))cosine similarity between receptionist and g, before neutralizing: 0.330779417506
cosine similarity between receptionist and g, after neutralizing: 8.4072919411e-18
3.2 - Equalization algorithm for gender-specific words
def equalize(pair, bias_axis, word_to_vec_map):
"""
Debias gender specific words by following the equalize method described in the figure above.
Arguments:
pair -- pair of strings of gender specific words to debias, e.g. ("actress", "actor")
bias_axis -- numpy-array of shape (50,), vector corresponding to the bias axis, e.g. gender
word_to_vec_map -- dictionary mapping words to their corresponding vectors
Returns
e_1 -- word vector corresponding to the first word
e_2 -- word vector corresponding to the second word
"""
### START CODE HERE ###
# Step 1: Select word vector representation of "word". Use word_to_vec_map. (≈ 2 lines)
w1, w2 = pair
e_w1, e_w2 = word_to_vec_map[w1],word_to_vec_map[w2]
# Step 2: Compute the mean of e_w1 and e_w2 (≈ 1 line)
mu = (e_w1+e_w2)/2
# Step 3: Compute the projections of mu over the bias axis and the orthogonal axis (≈ 2 lines)
mu_B = np.dot(mu,bias_axis)/np.sum(bias_axis*bias_axis)*bias_axis
mu_orth = mu-mu_B
# Step 4: Use equations (7) and (8) to compute e_w1B and e_w2B (≈2 lines)
e_w1B = np.dot(e_w1,bias_axis)/np.sum(bias_axis*bias_axis)*bias_axis
e_w2B = np.dot(e_w2,bias_axis)/np.sum(bias_axis*bias_axis)*bias_axis
# Step 5: Adjust the Bias part of e_w1B and e_w2B using the formulas (9) and (10) given above (≈2 lines)
corrected_e_w1B = np.sqrt(np.abs(1-np.sum(mu_orth*mu_orth)))*(e_w1B-mu_B)/np.linalg.norm(e_w1 - mu_orth - mu_B)
corrected_e_w2B = np.sqrt(np.abs(1-np.sum(mu_orth*mu_orth)))*(e_w2B-mu_B)/np.linalg.norm(e_w1 - mu_orth - mu_B)
# Step 6: Debias by equalizing e1 and e2 to the sum of their corrected projections (≈2 lines)
e1 = corrected_e_w1B+mu_orth
e2 = corrected_e_w2B+mu_orth
### END CODE HERE ###
return e1, e2print("cosine similarities before equalizing:")
print("cosine_similarity(word_to_vec_map[\"man\"], gender) = ", cosine_similarity(word_to_vec_map["man"], g))
print("cosine_similarity(word_to_vec_map[\"woman\"], gender) = ", cosine_similarity(word_to_vec_map["woman"], g))
print()
e1, e2 = equalize(("man", "woman"), g, word_to_vec_map)
print("cosine similarities after equalizing:")
print("cosine_similarity(e1, gender) = ", cosine_similarity(e1, g))
print("cosine_similarity(e2, gender) = ", cosine_similarity(e2, g))cosine similarities before equalizing:
cosine_similarity(word_to_vec_map[“man”], gender) = -0.117110957653
cosine_similarity(word_to_vec_map[“woman”], gender) = 0.356666188463
cosine similarities after equalizing:
cosine_similarity(e1, gender) = -0.700436428931
cosine_similarity(e2, gender) = 0.700436428931
