示例#1
0
def deserialize_random_forest(model_dict):
    model = RandomForestClassifier(**model_dict['params'])
    estimators = [deserialize_decision_tree(decision_tree) for decision_tree in model_dict['estimators_']]
    model.estimators_ = np.array(estimators)

    model.classes_ = np.array(model_dict['classes_'])
    model.n_features_ = model_dict['n_features_']
    model.n_outputs_ = model_dict['n_outputs_']
    model.max_depth = model_dict['max_depth']
    model.min_samples_split = model_dict['min_samples_split']
    model.min_samples_leaf = model_dict['min_samples_leaf']
    model.min_weight_fraction_leaf = model_dict['min_weight_fraction_leaf']
    model.max_features = model_dict['max_features']
    model.max_leaf_nodes = model_dict['max_leaf_nodes']
    model.min_impurity_decrease = model_dict['min_impurity_decrease']
    model.min_impurity_split = model_dict['min_impurity_split']

    if 'oob_score_' in model_dict:
        model.oob_score_ = model_dict['oob_score_']
    if 'oob_decision_function_' in model_dict:
        model.oob_decision_function_ = model_dict['oob_decision_function_']

    if isinstance(model_dict['n_classes_'], list):
        model.n_classes_ = np.array(model_dict['n_classes_'])
    else:
        model.n_classes_ = model_dict['n_classes_']

    return model
示例#2
0
文件: run_model.py 项目: t36li/FINRA
def RFC(x_train,y_train,x_test,udf_trees=100,udf_max_features='auto', udf_min_samples=50, do_CV=False,names=None):

	from sklearn.ensemble import RandomForestClassifier
	from sklearn.metrics import roc_auc_score

	if do_CV:
		param_grid = {'max_features': [2,3,4],
						'min_samples_leaf':[50,250,1000,2500]}

		est=RandomForestClassifier(n_estimators=100,verbose=1)
		cv_scores=list()
		params_list=list()

		start = time()
		for mfeatures in param_grid['max_features']:
			for minSamples in param_grid['min_samples_leaf']:
				print 'Trying parameter combination: (MaxFeatures=%i, minSamples=%i)' % (mfeatures,minSamples)
				est.min_samples_leaf=minSamples
				est.max_features=mfeatures

				cv_score=udf.cross_val_score_proba(x_train,y_train,5,est)
				cv_scores.append(np.mean(cv_score))

				### Create the labels for display purposes ###
				params_list.append((mfeatures,minSamples))

		print 'Took %.2f seconds for parameter tuning.' %(time()-start)
		print 'writing CV results to file...'
		results = np.array([params_list,cv_scores]).T ## should have 48 results...

		print 'Parameter tuning results........'
		print 'Parameters (max_features, min_samples_leaf), CV_Scores'
		for i in range(len(results)):
			print results[i]
	else:
		### Train the RFC Classifier with the optimal parameters found above ###
		print 'Fitting Random Forest with optimal user-defined parameters....'
		est=RandomForestClassifier(n_estimators=udf_trees, max_features=udf_max_features,min_samples_leaf=udf_min_samples,verbose=1)
		est.fit(x_train,y_train)
		y_pred=est.predict_proba(x_test)[:,1] ## Must predict probability!! ##

		### Plot feature importances ###
		plot_feature_importance(est, names)

		print 'Writing submission file....'
		with open('RFC_Submission.csv','wb') as testfile:
			w=csv.writer(testfile)
			w.writerow(('Id','Probability'))
			for i in range(len(y_pred)):
				w.writerow(((i+1),y_pred[i]))
		testfile.close()
		print 'File written to disk...' 
#causing problems.

rf = RandomForestClassifier(
    n_estimators=500,
    max_features=min(10, n_features),
    min_samples_leaf=1,
    random_state=42,
)
min_sample_class = min([sum(y_train == i) for i in set(y_train)])
res = []

if min_sample_class <= 1:
    print 'A training set has maximally one sample.'
else:
    for i in range(1, min_sample_class):
        rf.min_samples_leaf = i
        rf.fit(X_train, y_train)
        d = dict({'min_samples_leaf': i})
        d.update({'train': rf.score(X_train, y_train)})
        d.update({'test': rf.score(X_test, y_test)})
        res.append(d)
    res = pandas.DataFrame(res)
    res.plot('min_samples_leaf')
    plt.ylabel('Accuracy')
    plt.xlabel('Minimum number of samples in each leaf')
    plt.legend(loc='center left',
               bbox_to_anchor=(1, 0.5),
               title='Dataset',
               fancybox=False)
    plt.savefig('RF_accuracy_number_of_samples_per_leaf.png',
                dpi=300,
示例#4
0
文件: rtb.py 项目: zengqh/mydml
    lr.C = C
    this_scores = cross_val_score(lr, X, y, cv=4, scoring="roc_auc")
    scores.append(np.mean(this_scores))
    scores_std.append(np.std(this_scores))

lr_results = pd.DataFrame({'score': scores, 'C': C_s})
print(lr_results)

# RF
msl_s = [1, 2, 4, 8, 16, 32, 64, 128, 256]
scores = list()
scores = list()
rf = RandomForestClassifier(n_estimators=15)

for msl in msl_s:
    rf.min_samples_leaf = msl
    this_scores = cross_val_score(rf, X, y, cv=4, scoring='roc_auc')
    scores.append(np.mean(this_scores))
    scores_std.append(np.std(this_scores))

rf_results = pd.DataFrame({'score': scores, 'Minimum samples leaf': msl_s})
print(rf_results)

#svm
# print('begin svm')
# C_s = np.logspace(-10,1,11)
# scores = list()
# scores_std = list()
# svc = svm.SVC(kernel='linear', probability=True)
#
# for C in C_s: