General features selection based on certain machine learning algorithm and evaluation methods
Divesity, Flexible and Easy to use
More features selection method will be included in the future!
pip3 install MLFeatureSelection
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Modulus for selecting features based on greedy algorithm (from MLFeatureSelection import sequence_selection)
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Modulus for removing features based on features importance (from MLFeatureSelection import importance_selection)
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Modulus for removing features based on correlation coefficient (from MLFeatureSelection import coherence_selection)
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Modulus for reading the features combination from log file (from MLFeatureSelection.tools import readlog)
- sequence_selection
from MLFeatureSelection import sequence_selection
from sklearn.linear_model import LogisticRegression
sf = sequence_selection.Select(Sequence = True, Random = True, Cross = False)
sf.ImportDF(df,label = 'Label') #import dataframe and label
sf.ImportLossFunction(lossfunction, direction = 'ascend') #import loss function handle and optimize direction, 'ascend' for AUC, ACC, 'descend' for logloss etc.
sf.InitialNonTrainableFeatures(notusable) #those features that is not trainable in the dataframe, user_id, string, etc
sf.InitialFeatures(initialfeatures) #initial initialfeatures as list
sf.GenerateCol() #generate features for selection
sf.clf = LogisticRegression() #set the selected algorithm, can be any algorithm
sf.SetLogFile('record.log') #log file
sf.run(validate) #run with validation function, validate is the function handle of the validation function, return best features combination
- importance_selection
from MLFeatureSelection import importance_selection
import xgboost as xgb
sf = importance_selection.Select()
sf.ImportDF(df,label = 'Label') #import dataframe and label
sf.ImportLossFunction(lossfunction, direction = 'ascend') #import loss function and optimize direction
sf.InitialFeatures() #initial features, input
sf.SelectRemoveMode(batch = 2)
sf.clf = xgb.XGBClassifier()
sf.SetLogFile('record.log') #log file
sf.run(validate) #run with validation function, return best features combination
- coherence_selection
from MLFeatureSelection import coherence_selection
import xgboost as xgb
sf = coherence_selection.Select()
sf.ImportDF(df,label = 'Label') #import dataframe and label
sf.ImportLossFunction(lossfunction, direction = 'ascend') #import loss function and optimize direction
sf.InitialFeatures() #initial features, input
sf.SelectRemoveMode(batch = 2)
sf.clf = xgb.XGBClassifier()
sf.SetLogFile('record.log') #log file
sf.run(validate) #run with validation function, return best features combination
- log reader
from MLFeatureSelection.tools import readlog
logfile = 'record.log'
logscore = 0.5 #any score in the logfile
features_combination = readlog(logfile, logscore)
- format of validate and lossfunction
define your own:
validate: validation method in function , ie k-fold, last time section valdate, random sampling validation, etc
lossfunction: model performance evaluation method, ie logloss, auc, accuracy, etc
def validate(X, y, features, clf, lossfunction):
"""define your own validation function with 5 parameters
input as X, y, features, clf, lossfunction
clf is set by SetClassifier()
lossfunction is import earlier
features will be generate automatically
function return score and trained classfier
"""
clf.fit(X[features],y)
y_pred = clf.predict(X[features])
score = lossfuntion(y_pred,y)
return score, clf
def lossfunction(y_pred, y_test):
"""define your own loss function with y_pred and y_test
return score
"""
return np.mean(y_pred == y_test)
More examples are added in example folder include:
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Demo contain all modulus can be found here (demo)
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Simple Titanic with 5-fold validation and evaluated by accuracy (demo)
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Demo for S1, S2 score improvement in JData 2018 predict purchase time competition (demo)
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Demo for IJCAI 2018 CTR prediction (demo)
- better API introduction will be completed next before the end of 06/2018
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1st in Rong360
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6th in JData-2018 (Peter Du)
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12nd in IJCAI-2018 1st round
Sequence (bool, optional, (defualt=True)) - switch for sequence selection selection include forward,backward and simulate anneal selection
Random (bool, optional, (defualt=True)) - switch for randomly selection of features combination
Cross (bool, optional, (defualt=True)) - switch for cross term generate, need to set sf.ImportCrossMethod() after
df (pandas.DataFrame) - dataframe includes include all features
label (str) - name of the label column
lossfunction (function handle) - handle of the loss function, function should return score as float (logloss, AUC, etc)
direction (str,'ascend'/'descend') - direction to improve, 'descend' for logloss, 'ascend' for AUC, etc
features (list, optional, (defualt=[])) - list of initial features combination, empty list will drive code to start from nothing list with all trainable features will drive code to start backward searching at the beginning
features (list) - list of features that not trainable (labelname, string, datetime, etc)
key (str, optional, default=None) - only the features with keyword will be seleted, default to be None
selectstep (int, optional, default=1) - value for features selection step
frac (float, optional, default=1) - percentage of delete features from all features default to be set as using the batch
batch (int, optional, default=1) - delete features quantity every iteration
key (str, optional, default=None) - only delete the features with keyword
CrossMethod (dict) - different cross method like add, divide, multiple and substraction
features (list, optional, default=[]_) - list of strong features, switch for simulate anneal
TimeLimit (float, optional, default=inf) - maximum running time, unit in minute
FeaturesLimit (int, optional, default=inf_) - maximum feature quantity
clf (predictor) - classfier or estimator, sklearn, xgboost, lightgbm, etc. Need to match the validate function
logfile (str) - log file name
validate (function handle) - function return evaluation score and predictor input features dataset X, label series Y, used features, predictor, lossfunction handle