In case of 3 columns data, (In my test case) I can see that all the columns are valued as equal.
random_forest.feature_importances_
array([0.3131602 , 0.31915436, 0.36768544])
Is there any way to add waitage to one of the columns?
Update:
I guess xgboost can be used in this case.
I tried, but getting this error:
import xgboost as xgb
param = {}
num_round = 2
dtrain = xgb.DMatrix(X, y)
dtest = xgb.DMatrix(x_test_split)
dtrain_split = xgb.DMatrix(X_train, label=y_train)
dtest_split = xgb.DMatrix(X_test)
gbdt = xgb.train(param, dtrain_split, num_round)
y_predicted = gbdt.predict(dtest_split)
rmse_pred_vs_actual = xgb.rmse(y_predicted, y_test)
AttributeError: module 'xgboost' has no attribute 'rmse'
Error is by assuming xgb has method "rmse":
rmse_pred_vs_actual = xgb.rmse(y_predicted, y_test)
It is literally written: AttributeError: module 'xgboost' has no attribute 'rmse'
Use sklearn.metrics.mean_squared_error
By:
from sklearn.metrics import mean_squared_error
# Your code
rmse_pred_vs_actual = mean_squared_error(y_test, y_predicted)
It'll fix your error but it still doesn't control a feature importance.
Now, if you really want to change the importance of a feature, you need to be creative about how to make a change like this. There is no text book solution that I know of and no method in xgboost that I know of. You can follow the link Stev posted in a comment to your question and maybe get some ideas (including changing your ML algorithm).
Related
I am trying to run the GluonTS example code, going through some struggle to install the libraries, now I get the following error:
FileNotFoundError: C:\Users\abcde\.mxnet\gluon-ts\datasets\airpassengers\test
The C:\Users\abcde\.mxnet\gluon-ts\datasets\airpassengers\ does exist but contains only train folder. Have tried reinstalling but to no avail. Any ideas how to fix this and run the example, even if finding the dataset in correct format elsewhere?
EDIT: To clarify, I was referring to an example on https://ts.gluon.ai/stable/
import matplotlib.pyplot as plt
from gluonts.dataset.util import to_pandas
from gluonts.dataset.pandas import PandasDataset
from gluonts.dataset.repository.datasets import get_dataset
from gluonts.mx import DeepAREstimator, Trainer
dataset = get_dataset("airpassengers")
deepar = DeepAREstimator(prediction_length=12, freq="M", trainer=Trainer(epochs=5))
model = deepar.train(dataset.train)
# Make predictions
true_values = to_pandas(list(dataset.test)[0])
true_values.to_timestamp().plot(color="k")
prediction_input = PandasDataset([true_values[:-36], true_values[:-24], true_values[:-12]])
predictions = model.predict(prediction_input)
for color, prediction in zip(["green", "blue", "purple"], predictions):
prediction.plot(color=f"tab:{color}")
plt.legend(["True values"], loc="upper left", fontsize="xx-large")
There was an incorrect import on the earlier version of the example, which was since corrected, also I needed to specify regenerate=True while getting the dataset, so:
dataset = get_dataset("airpassengers", regenerate=True).
I'm fairly new to machine learning and I am using the following code to encode my categorical data for preprocessing:
from sklearn.preprocessing import LabelEncoder, OneHotEncoder
from sklearn.compose import ColumnTransformer
ct = ColumnTransformer([('one_hot_encoder', OneHotEncoder(handle_unknown = 'ignore'), [0])],remainder='passthrough')
X = np.array(ct.fit_transform(X), dtype=np.float)
which works when I only have one categorical column of data in X.
However when I have multiple columns of categorical data I change my code to :
ct = ColumnTransformer([('one_hot_encoder', OneHotEncoder(handle_unknown = 'ignore'), [0,1,2,3,4,5,10,14,15])],remainder='passthrough')
but I get the following error when calling the np.array function:
Value Error: setting an array element with a sequence
on the np.array function call...
From what I understand all I need to do is specify which columns I'm hot encoding as in the above line of code...so why does one work and the other give an error? What should I do to fix it?
Also: if I remove the
dtype=np.float
from the np.array function I don't get an error - but I also don't get anything returned in X
Never mind I was able to answer my own question.
For anyone interested what I did was change the line
X = np.array(ct.fit_transform(X), dtype=np.float)
to:
X = ct.fit_transform(X).toarray()
The code works perfectly now.
from sklearn.feature_extraction.text import TfidfVectorizer, CountVectorizer
Hello I have the following list of comments:
comments = ['I am very agry','this is not interesting','I am very happy']
These are the corresponding labels:
sents = ['angry','indiferent','happy']
I am using tfidf to vectorize these comments as follows:
tfidf_vectorizer = TfidfVectorizer(analyzer='word')
tfidf = tfidf_vectorizer.fit_transform(comments)
from sklearn import preprocessing
I am using label encoder to vectorize the labels:
le = preprocessing.LabelEncoder()
le.fit(sents)
labels = le.transform(sents)
print(labels.shape)
from sklearn.linear_model import PassiveAggressiveClassifier
from sklearn.model_selection import train_test_split
with open('tfidf.pickle','wb') as idxf:
pickle.dump(tfidf, idxf, pickle.HIGHEST_PROTOCOL)
with open('tfidf_vectorizer.pickle','wb') as idxf:
pickle.dump(tfidf_vectorizer, idxf, pickle.HIGHEST_PROTOCOL)
Here I am using passive aggressive to fit the model:
clf2 = PassiveAggressiveClassifier()
with open('passive.pickle','wb') as idxf:
pickle.dump(clf2, idxf, pickle.HIGHEST_PROTOCOL)
with open('passive.pickle', 'rb') as infile:
clf2 = pickle.load(infile)
with open('tfidf_vectorizer.pickle', 'rb') as infile:
tfidf_vectorizer = pickle.load(infile)
with open('tfidf.pickle', 'rb') as infile:
tfidf = pickle.load(infile)
Here I am trying to test the usage of partial fit as follows with three new comments and their corresponding labels:
new_comments = ['I love the life','I hate you','this is not important']
new_labels = [1,0,2]
vec_new_comments = tfidf_vectorizer.transform(new_comments)
print(clf2.predict(vec_new_comments))
clf2.partial_fit(vec_new_comments, new_labels)
The problem is that I am not getting the right results after the partial fit as follows:
print('AFTER THIS UPDATE THE RESULT SHOULD BE 1,0,2??')
print(clf2.predict(vec_new_comments))
however I am getting this output:
[2 2 2]
So I really appreciate support to find, why the model is not being updated if I am testing it with the same examples that it has used to be trained the desired output should be:
[1,0,2]
I would like to appreciate support to ajust maybe the hyperparameters to see the desired output.
this is the complete code, to show the partial fit:
from sklearn.feature_extraction.text import TfidfVectorizer, CountVectorizer
import sys
from sklearn.metrics.pairwise import cosine_similarity
import random
comments = ['I am very agry','this is not interesting','I am very happy']
sents = ['angry','indiferent','happy']
tfidf_vectorizer = TfidfVectorizer(analyzer='word')
tfidf = tfidf_vectorizer.fit_transform(comments)
#print(tfidf.shape)
from sklearn import preprocessing
le = preprocessing.LabelEncoder()
le.fit(sents)
labels = le.transform(sents)
from sklearn.linear_model import PassiveAggressiveClassifier
from sklearn.model_selection import train_test_split
with open('tfidf.pickle','wb') as idxf:
pickle.dump(tfidf, idxf, pickle.HIGHEST_PROTOCOL)
with open('tfidf_vectorizer.pickle','wb') as idxf:
pickle.dump(tfidf_vectorizer, idxf, pickle.HIGHEST_PROTOCOL)
clf2 = PassiveAggressiveClassifier()
clf2.fit(tfidf, labels)
with open('passive.pickle','wb') as idxf:
pickle.dump(clf2, idxf, pickle.HIGHEST_PROTOCOL)
with open('passive.pickle', 'rb') as infile:
clf2 = pickle.load(infile)
with open('tfidf_vectorizer.pickle', 'rb') as infile:
tfidf_vectorizer = pickle.load(infile)
with open('tfidf.pickle', 'rb') as infile:
tfidf = pickle.load(infile)
new_comments = ['I love the life','I hate you','this is not important']
new_labels = [1,0,2]
vec_new_comments = tfidf_vectorizer.transform(new_comments)
clf2.partial_fit(vec_new_comments, new_labels)
print('AFTER THIS UPDATE THE RESULT SHOULD BE 1,0,2??')
print(clf2.predict(vec_new_comments))
However I got:
AFTER THIS UPDATE THE RESULT SHOULD BE 1,0,2??
[2 2 2]
Well there are multiple problems with your code. I will start by stating the obvious ones to more complex ones:
You are pickling the clf2 before it has learnt anything. (ie. you pickle it as soon as it is defined, it doesnt serve any purpose). If you are only testing, then fine. Otherwise they should be pickled after the fit() or equivalent calls.
You are calling clf2.fit() before the clf2.partial_fit(). This defeats the whole purpose of partial_fit(). When you call fit(), you essentially fix the classes (labels) that the model will learn about. In your case it is acceptable, because on your subsequent call to partial_fit() you are giving the same labels. But still it is not a good practice.
See this for more details
In a partial_fit() scenario, dont call the fit() ever. Always call the partial_fit() with your starting data and new coming data. But make sure that you supply all the labels you want the model to learn in the first call to parital_fit() in a parameter classes.
Now the last part, about your tfidf_vectorizer. You call fit_transform()(which is essentially fit() and then transformed() combined) on tfidf_vectorizer with comments array. That means that it on subsequent calls to transform() (as you did in transform(new_comments)), it will not learn new words from new_comments, but only use the words which it saw during the call to fit()(words present in comments).
Same goes for LabelEncoder and sents.
This again is not prefereble in a online learning scenario. You should fit all the available data at once. But since you are trying to use the partial_fit(), we assume that you have very large dataset which may not fit in memory at once. So you would want to apply some sort of partial_fit to TfidfVectorizer as well. But TfidfVectorizer doesnt support partial_fit(). In fact its not made for large data. So you need to change your approach. See the following questions for more details:-
Updating the feature names into scikit TFIdfVectorizer
How can i reduce memory usage of Scikit-Learn Vectorizers?
All things aside, if you change just the tfidf part of fitting the whole data (comments and new_comments at once), you will get your desired results.
See the below code changes (I may have organized it a bit and renamed vec_new_comments to new_tfidf, please go through it with attention):
comments = ['I am very agry','this is not interesting','I am very happy']
sents = ['angry','indiferent','happy']
new_comments = ['I love the life','I hate you','this is not important']
new_sents = ['happy','angry','indiferent']
tfidf_vectorizer = TfidfVectorizer(analyzer='word')
le = preprocessing.LabelEncoder()
# The below lines are important
# I have given the whole data to fit in tfidf_vectorizer
tfidf_vectorizer.fit(comments + new_comments)
# same for `sents`, but since the labels dont change, it doesnt matter which you use, because it will be same
# le.fit(sents)
le.fit(sents + new_sents)
Below is the Not so preferred code (which you are using, and about which I talked in point 2), but results are good as long as you make the above changes.
tfidf = tfidf_vectorizer.transform(comments)
labels = le.transform(sents)
clf2.fit(tfidf, labels)
print(clf2.predict(tfidf))
# [0 2 1]
new_tfidf = tfidf_vectorizer.transform(new_comments)
new_labels = le.transform(new_sents)
clf2.partial_fit(new_tfidf, new_labels)
print(clf2.predict(new_tfidf))
# [1 0 2] As you wanted
Correct approach, or the way partial_fit() is intended to be used:
# Declare all labels that you want the model to learn
# Using classes learnt by labelEncoder for this
# In any calls to `partial_fit()`, all labels should be from this array only
all_classes = le.transform(le.classes_)
# Notice the parameter classes here
# It needs to present first time
clf2.partial_fit(tfidf, labels, classes=all_classes)
print(clf2.predict(tfidf))
# [0 2 1]
# classes is not present here
clf2.partial_fit(new_tfidf, new_labels)
print(clf2.predict(new_tfidf))
# [1 0 2]
I have a very simple dataset for binary classification in csv file which looks like this:
"feature1","feature2","label"
1,0,1
0,1,0
...
where the "label" column indicates class (1 is positive, 0 is negative). The number of features is actually pretty big but it doesn't matter for that question.
Here is how I read the data:
train = pandas.read_csv(TRAINING_FILE)
y_train, X_train = train['label'], train[['feature1', 'feature2']].fillna(0)
test = pandas.read_csv(TEST_FILE)
y_test, X_test = test['label'], test[['feature1', 'feature2']].fillna(0)
I want to run tensorflow.contrib.learn.LinearClassifier and tensorflow.contrib.learn.DNNClassifier on that data. For instance, I initialize DNN like this:
classifier = DNNClassifier(hidden_units=[3, 5, 3],
n_classes=2,
feature_columns=feature_columns, # ???
activation_fn=nn.relu,
enable_centered_bias=False,
model_dir=MODEL_DIR_DNN)
So how exactly should I create the feature_columns when all the features are also binary (0 or 1 are the only possible values)?
Here is the model training:
classifier.fit(X_train.values,
y_train.values,
batch_size=dnn_batch_size,
steps=dnn_steps)
The solution with replacing fit() parameters with the input function would also be great.
Thanks!
P.S. I'm using TensorFlow version 1.0.1
You can directly use tf.feature_column.numeric_column :
feature_columns = [tf.feature_column.numeric_column(key = key) for key in X_train.columns]
I've just found the solution and it's pretty simple:
feature_columns = tf.contrib.learn.infer_real_valued_columns_from_input(X_train)
Apparently infer_real_valued_columns_from_input() works well with categorical variables.
I am trying to run MultinomiaL Naive bayes and receiving the below error. Sample training data is given. Test data is exactly similar.
def main():
text_train, targets_train = read_data('train')
text_test, targets_test = read_data('test')
classifier1 = MultinomialNB()
classifier1.fit(text_train, targets_train)
prediction1 = classifier1.predict(text_test)
Sample Data:
Train:
category, text
Family, I love you Mom
University, I hate this course
Sometimes I face this question and find most of reason from the error is the input data should be 2-D array, such as if you want to build a regression model. you write this code and then you will face this error!
for example:
a = np.array([1,2,3]).T
b = np.array([4,5,6]).T
regr = linear_model.LinearRegression()
regr.fit(a, b)
then you should add something!
a = np.array([[1,2,3]]).T
b = np.array([[4,5,6]]).T
lastly you will be run normally!
so it is just my empirical!
This is just a reference, not a standard answer！
i am from Chinese as a student in learning English and python!