def train_model_cv(self,
train_file,
normalize,
is_bool_value,
is_percentage,
cv=10,
save_model=False):
# training
features_array, label_array, feature_names = self.get_features_array_label_array_from_file(
train_file,
normalize=normalize,
is_bool_value=is_bool_value,
is_percentage=is_percentage)
# TODO: you can change the model here. Now we are using 10-cross valication for the model.
# self.model = LinearRegression(copy_X=True, fit_intercept=True, n_jobs=1, normalize=False)
# self.model = linear_model.Lasso(alpha = 0.1)
self.model = linear_model.LassoCV(cv=cv,
normalize=False,
verbose=True,
max_iter=10000)
print("Model Settings:", self.model)
self.model.fit(features_array, label_array)
self.print_linear_regression_formular(feature_names)
def model_lasso(s, t, s_, t_, flagCV, nFeat):
if flagCV:
#bad r2
#http://scikit-learn.org/stable/modules/generated/sklearn.linear_model.LassoCV.html#sklearn.linear_model.LassoCV
clf = sklm.LassoCV(eps=0.001, n_alphas=100, alphas=None, fit_intercept=True, normalize=False, \
precompute='auto', max_iter=1000, tol=0.0001, copy_X=True, cv=None, \
verbose=False, n_jobs=1, positive=False, random_state=None, \
selection='cyclic')
else:
#http://scikit-learn.org/stable/modules/generated/sklearn.linear_model.Lasso.html#sklearn.linear_model.Lasso
clf = sklm.Lasso(alpha=1.0, fit_intercept=True, normalize=False, precompute=False, \
copy_X=True, max_iter=1000, tol=0.0001, warm_start=False, positive=False,\
random_state=None, selection='cyclic')
clf.fit(s, t)
print 'coeffs = ', clf.coef_, ' intercept = ', clf.intercept_
feature_imp = clf.coef_
feature_imp_ind_neg = feature_imp.argsort()[0:nFeat]
feature_imp_ind_pos = feature_imp.argsort()[-nFeat:][::-1]
print 'feature_imp_ind_neg=', feature_imp_ind_neg, 'feature_imp_ind_pos=', feature_imp_ind_pos
r2_train = clf.score(s, t)
r2_test = clf.score(s_, t_)
print 'r2_train=', r2_train, ' r2_test=', r2_test
def franke_lasso(n=10000, eps=0.0):
max_order = 5
x = rng.uniform(size=n)
y = rng.uniform(size=n)
err = eps * rng.normal(size=n)
x_train = x[:int(n / 2)]
y_train = y[:int(n / 2)]
err_train = err[:int(n / 2)]
x_valid = x[int(n / 2):]
y_valid = y[int(n / 2):]
err_valid = err[:int(n / 2)]
z_train = FrankeFunction(x_train, y_train) + err_train
z_valid = FrankeFunction(x_valid, y_valid) + err_valid
xb = np.column_stack(sol_tup(x_train, y_train, max_order))
lasso = linear_model.LassoCV(max_iter=100000, cv=5)
lasso.fit(xb, z_train)
predl = lasso.predict(np.column_stack(sol_tup(x_valid, y_valid,
max_order)))
return lasso.coef_, mean_squared_error(z_valid,
predl), r2_score(z_valid, predl)
def fs_lasso_cv(X,
y,
feat_list,
n_alphas=1000,
cv=10,
tol=0.00001,
max_iter=10000,
hard_shrink=None):
'''Wrapper function to build a LassoCV model from sklearn and return important features'''
lcv = linear_model.LassoCV(n_jobs=max(1,
mp.cpu_count() - 1),
n_alphas=n_alphas,
cv=cv,
tol=tol,
max_iter=max_iter)
coefs = lcv.fit(X, y).coef_
# force shrinkage to zero if hard_shrink is provided
if hard_shrink is not None: np.place(coefs, np.abs(coefs) < hard_shrink, 0)
selected_feats = list(it.compress(feat_list, coefs))
return selected_feats
def lasso_regression(X_train, y_train, X_test, y_test, normalize=False):
print("-------------------------- Lasso Regression")
clf = linear_model.LassoCV(alphas=np.arange(0.1, 2, 0.1), max_iter=5000)
clf.fit(X_train, y_train)
# Make predictions using the testing set
y_pred = clf.predict(X_test)
# The intercept
print("Intercept: %.4f" % clf.intercept_)
# The mean squared error
print("Mean squared error: %.2f"
% mean_squared_error(y_test, y_pred))
# Explained variance score: 1 is perfect prediction
print('Coefficient of determination(R^2): %.2f' % r2_score(y_test, y_pred))
# The coefficients
cols = X_train.columns.tolist()
coef = clf.coef_.tolist()
coef = list(zip(cols, coef))
df_coef = pd.DataFrame.from_records(coef)
print('Coefficients: \n', df_coef.T)
print('Alpha: \n', clf.alpha_)
return clf
import numpy as np
from sklearn import cross_validation, datasets, linear_model
diabetes = datasets.load_diabetes()
X = diabetes.data
y = diabetes.target
alphas = np.logspace(-4, -.5, 30)
lasso_cv = linear_model.LassoCV(alphas=alphas)
k_fold = cross_validation.KFold(len(X), 5)
alphas = np.logspace(-4, -.5, 30)
for k, (train, test) in enumerate(k_fold):
lasso_cv.fit(X[train], y[train])
print("[fold {0}] alpha: {1:.5f}, score: {2:.5f}".
format(k, lasso_cv.alpha_, lasso_cv.score(X[test], y[test])))
speed_corr_neurons = template_info.loc[speed_corr_neurons_index]
# Standartize X, Y
Y = preprocessing.StandardScaler().\
fit_transform(np.reshape(speeds_0p25[:-1], (-1, 1))).reshape(-1)
X = preprocessing.StandardScaler().\
fit_transform(spike_rates_0p25[speed_corr_neurons_index].transpose())
# Or not
Y = np.array(speeds_0p25)
X = spike_rates_0p25[speed_corr_neurons_index].transpose()
# Set up the regressors
model_linear = linear_model.LinearRegression(fit_intercept=True)
model_lassoCV = linear_model.LassoCV(cv=5, fit_intercept=True)
model_lasso = linear_model.Lasso(alpha=0.02,
fit_intercept=True,
max_iter=10000,
normalize=False)
model_gam = pg.LinearGAM()
Y = np.exp(Y) / (np.exp(Y) + 1)
model_gam = pg.GammaGAM()
# Split the data to train and test sets
X_train, X_test, Y_train, Y_test = model_selection.train_test_split(
X, Y, test_size=0.2, random_state=0)
# Fit
model = model_gam
# boston_X_test_scaled = boston_X_scaled[-20:]
# boston_y_train = boston.target[:-20]
# boston_y_test = boston.target[-20:]
# Prepare ensemble regressors
regressors = (
linear_model.LinearRegressi on(fit_intercept=True),
Pipeline(
[('poly', PolynomialFeatures(degree=2)),
('linear', linear_model.LinearRegression(fit_intercept=False))]
),
linear_model.Ridge(alpha=.1, fit_intercept=True),
linear_model.RidgeCV(alphas=[.01, .1, .3, .5, 1], fit_intercept=True),
linear_model.Lasso(alpha=1, fit_intercept=True),
linear_model.LassoCV(n_alphas=100, fit_intercept=True),
linear_model.ElasticNet(alpha=1),
linear_model.ElasticNetCV(n_alphas=100, l1_ratio=.5),
linear_model.OrthogonalMatchingPursuit(),
linear_model.BayesianRidge(),
linear_model.ARDRegression(),
linear_model.SGDRegressor(),
linear_model.PassiveAggressiveRegressor(loss='squared_epsilon_insensitive'),
linear_model.RANSACRegressor(),
LinearSVR(max_iter=1e4, fit_intercept=True, loss='squared_epsilon_insensitive', C=0.5),
SVR(max_iter=1e4, kernel='poly', C=1, degree=4),
SVR(max_iter=1e4, kernel='rbf', C=1, gamma=0.1),
SVR(kernel='linear', C=1),
SVR(kernel='linear', C=0.5),
SVR(kernel='linear', C=0.1),
DecisionTreeRegressor(max_depth=5),
l_eye = l[idx] * np.eye(X.shape[1])
H_ridge = np.linalg.inv(X.T.dot(X) + l_eye)
beta_ridge = H_ridge.dot(X.T).dot(z_flat)
z_tilde_ridge = X @ beta_ridge
plt.figure()
plt.title('Terrain data from Norway after ridge regression')
plt.imshow(np.reshape(z_tilde_ridge, np.shape(z)), cmap='gray')
plt.xlabel('X')
plt.ylabel('Y')
save_fig('SRTM_data_Norway_1_ridge_regression')
# lasso
lasso=linear_model.LassoCV(max_iter=1000000, cv=5)
lasso.fit(X[:,1:], z_flat)
predl=lasso.predict(X[:,1:])
plt.figure()
plt.title('Terrain data from Norway after lasso')
plt.imshow(np.reshape(predl, np.shape(z)), cmap='gray')
plt.xlabel('X')
plt.ylabel('Y')
save_fig('SRTM_data_Norway_1_lasso')
## compressing image data (unused)
r = 20
U, S, V = np.linalg.svd(z) #using SVD method to decompose image
def __init__(
self,
method,
yrange,
params,
i=0
): #TODO: yrange doesn't currently do anything. Remove or do something with it!
self.algorithm_list = [
'PLS',
'GP',
'OLS',
'OMP',
'Lasso',
'Elastic Net',
'Ridge',
'Bayesian Ridge',
'ARD',
'LARS',
'LASSO LARS',
'SVR',
'KRR',
]
self.method = method
self.outliers = None
self.ransac = False
print(params)
if self.method[i] == 'PLS':
self.model = PLSRegression(**params[i])
if self.method[i] == 'OLS':
self.model = linear.LinearRegression(**params[i])
if self.method[i] == 'OMP':
# check whether to do CV or not
self.do_cv = params[i]['CV']
# create a temporary set of parameters
params_temp = copy.copy(params[i])
# Remove CV parameter
params_temp.pop('CV')
if self.do_cv is False:
self.model = linear.OrthogonalMatchingPursuit(**params_temp)
else:
params_temp.pop('precompute')
self.model = linear.OrthogonalMatchingPursuitCV(**params_temp)
if self.method[i] == 'LASSO':
# create a temporary set of parameters
params_temp = copy.copy(params[i])
# check whether to do CV or not
try:
self.do_cv = params[i]['CV']
# Remove CV parameter
params_temp.pop('CV')
except:
self.do_cv = False
if self.do_cv is False:
self.model = linear.Lasso(**params_temp)
else:
params_temp.pop('alpha')
self.model = linear.LassoCV(**params_temp)
if self.method[i] == 'Elastic Net':
params_temp = copy.copy(params[i])
try:
self.do_cv = params[i]['CV']
params_temp.pop('CV')
except:
self.do_cv = False
if self.do_cv is False:
self.model = linear.ElasticNet(**params_temp)
else:
params_temp['l1_ratio'] = [.1, .5, .7, .9, .95, .99, 1]
self.model = linear.ElasticNetCV(**params_temp)
if self.method[i] == 'Ridge':
# create a temporary set of parameters
params_temp = copy.copy(params[i])
try:
# check whether to do CV or not
self.do_cv = params[i]['CV']
# Remove CV parameter
params_temp.pop('CV')
except:
self.do_cv = False
if self.do_cv:
self.model = linear.RidgeCV(**params_temp)
else:
self.model = linear.Ridge(**params_temp)
if self.method[i] == 'BRR':
self.model = linear.BayesianRidge(**params[i])
if self.method[i] == 'ARD':
self.model = linear.ARDRegression(**params[i])
if self.method[i] == 'LARS':
# create a temporary set of parameters
params_temp = copy.copy(params[i])
try:
# check whether to do CV or not
self.do_cv = params[i]['CV']
# Remove CV parameter
params_temp.pop('CV')
except:
self.do_cv = False
if self.do_cv is False:
self.model = linear.Lars(**params_temp)
else:
self.model = linear.LarsCV(**params_temp)
if self.method[i] == 'LASSO LARS':
model = params[i]['model']
params_temp = copy.copy(params[i])
params_temp.pop('model')
if model == 0:
self.model = linear.LassoLars(**params_temp)
elif model == 1:
self.model = linear.LassoLarsCV(**params_temp)
elif model == 2:
self.model = linear.LassoLarsIC(**params_temp)
else:
print("Something went wrong, \'model\' should be 0, 1, or 2")
if self.method[i] == 'SVR':
self.model = svm.SVR(**params[i])
if self.method[i] == 'KRR':
self.model = kernel_ridge.KernelRidge(**params[i])
if self.method[i] == 'GP':
# get the method for dimensionality reduction and the number of components
self.reduce_dim = params[i]['reduce_dim']
self.n_components = params[i]['n_components']
# create a temporary set of parameters
params_temp = copy.copy(params[i])
# Remove parameters not accepted by Gaussian Process
params_temp.pop('reduce_dim')
params_temp.pop('n_components')
self.model = GaussianProcess(**params_temp)
# print('Final prediction score with optimal: [%.8f](use RF)' % mean_absolute_error(y_test, y_pred))
#
# '''5. just use the EXTRA'''
# model = ExtraTreesRegressor(random_state=0, n_estimators=100)
# model.fit(X_train, y_train)
# y_pred = model.predict(X_test)
# print('Final prediction score with optimal: [%.8f](use EXTRA)' % mean_absolute_error(y_test, y_pred))
#
# '''6. just use the XGB'''
# model = XGBRegressor(random_state=0,n_estimators=100, n_jobs=-1)
# model.fit(X_train, y_train)
# y_pred = model.predict(X_test)
# print('Final prediction score with optimal: [%.8f](use XGB)' % mean_absolute_error(y_test, y_pred))
models = [
linear_model.LassoCV(random_state=0, n_jobs=1),
GradientBoostingRegressor(random_state=0),
SVR(),
RandomForestRegressor(random_state=0,
n_jobs=1,
n_estimators=100,
max_depth=3),
ExtraTreesRegressor(random_state=0, n_estimators=100),
XGBRegressor(random_state=0, n_estimators=100, n_jobs=1)
]
# # '''With optimal'''
model = Superknn(models=models,
metric=mean_absolute_error,
n_jobs=10,
random_state=0,
folds=5)
def selectByLassoL1(X, y, value, diagnose=False):
'''
Select the features using lasso regression
Parameters
----------
X : TYPE pandas dataframe
DESCRIPTION. dataframe of the attributes
y : TYPE pandas dataframe
DESCRIPTION. dataframe with the target variable
value : TYPE float
DESCRIPTION. correlation treshold 0->1
diagnose : TYPE, optional if true generates the correlation of each variable to the target var
DESCRIPTION. The default is False.
Returns
-------
res : TYPE pandas dataframe
DESCRIPTION. output dataframe with selected variables
output_figure : TYPE dictionary
DESCRIPTION. dictionary containing the figures with the plot of the selected features depending o the variance
'''
output_figure = {}
#lasso feature selection works for regression models
Q = dummyColumns(X)
clf = linear_model.LassoCV(cv=5)
if diagnose:
numFeatSelected = []
for i in range(1, 101):
val = i / 100
sfm = SelectFromModel(clf, threshold=val)
sfm.fit(Q, y)
nn = len(Q.columns[sfm.get_support()])
#print(nn)
numFeatSelected.append(nn)
fig1 = plt.figure()
plt.plot(range(1, 101), numFeatSelected)
plt.title('Lasso graph')
plt.xlabel('Coeff threshold %')
plt.ylabel('Num. selected features')
output_figure['LassoChart'] = fig1
plt.close('all')
#_, _, _, alphaValue, _= LassoRegressionCV(Q,y,'',nFolds=5, saveFig=False) #previous version with lasso from ZO_RegressionLinearModel
#las=LassoRegressionComplete(Q,y,alphaValue)
sfm = SelectFromModel(clf, threshold=value)
sfm.fit(Q, y)
#n_features = sfm.transform(X).shape[1]
#model = SelectFromModel(las, prefit=True,threshold=0.25)
Z = sfm.transform(Q)
feature_idx = sfm.get_support()
feature_name = Q.columns[feature_idx]
res = pd.DataFrame(Z, columns=feature_name)
return res, output_figure
def organize_data(ManagerID, data_mktbeta, data_indubeta, data_FAndMdata,
startdatestr, enddatestr, ob_win):
"""
give ManagerID, organize data to store in sql
ob_win: ob window length
return result_df
"""
# print(datetime.datetime.now())
# print('Start organize data of: ' + ManagerID)
# read mng record data
data_allrecord = data_FAndMdata[data_FAndMdata.ManagerID == ManagerID]
# store
cols = ['ID', 'EndDate', 'InvestAdvisor', 'ManagerID', 'Ret']
result_df = pd.DataFrame(columns=cols) # store here
# 先算出复合收益率
time_array = data_allrecord.EndDate.unique()
for date in time_array:
data_subrecord = data_allrecord[data_allrecord.EndDate == date]
wgted_ret = 0
wgt = 0
InAdv = ''
for index, row in data_subrecord.iterrows():
wgt += 1 / row.ManagersofFund
wgted_ret += row.dailyreturn / row.ManagersofFund
InAdv = row.InvestAdvisorAbbrName
ret = wgted_ret / wgt
if np.isnan(ret):
continue
else:
IDstr = ManagerID + pd.to_datetime(date).strftime('%Y%m%d')
result_df = result_df.append(dict(
zip(cols, [IDstr, date, InAdv, ManagerID, ret])),
ignore_index=True)
# 业绩分解
# fetch index data and construct np.array
addcols = [
'beta_mkt1',
'beta_mkt2',
'beta_mkt3',
'name_mkt1',
'name_mkt2',
'name_mkt3',
'intercept_mkt',
'score_mkt',
'bias_ret_mkt',
'bias_var_mkt',
'bias_score_mkt', # bias mkt: 风格的偏离
'beta_indu1',
'beta_indu2',
'beta_indu3',
'name_indu1',
'name_indu2',
'name_indu3',
'intercept_indu',
'score_indu',
'bias_ret_indu',
'bias_var_indu',
'bias_score_indu'
] # bias indu：行业的偏离
newcols = cols + addcols
result_df = result_df.reindex(columns=newcols)
idx = 0
# total = len(result_df)
while idx < len(result_df):
if idx < ob_win - 1:
# no enough data
# print('line:' + str(idx) + '/' + str(total) + ', skip')
idx += 1
continue
else:
# get date
obdates = result_df.iloc[(idx - ob_win + 1):(idx + 1)].EndDate
timegap = (obdates.iloc[-1] - obdates.iloc[0]).days
if timegap / ob_win > 9 / 5:
# dates not continuous
# print('line:' + str(idx) + '/' + str(total) + ', skip')
idx += 1
continue
else:
# calc
mng_ret = result_df.iloc[(idx - ob_win + 1):(idx + 1)].Ret
mkt_ret = data_mktbeta.loc[obdates]
indu_ret = data_indubeta.loc[obdates]
mng_ret = mng_ret.values
mkt_ret = mkt_ret.values
indu_ret = indu_ret.values
# remove NaN rows
isnanrow = np.isnan(mkt_ret[:, 1])
mng_ret = mng_ret[~isnanrow]
mkt_ret = mkt_ret[~isnanrow]
indu_ret = indu_ret[~isnanrow]
# define mkt model
model = linear_model.LassoCV(
positive=True,
cv=int(ob_win / 30), # subsample size = 30
selection='random',
fit_intercept=True,
normalize=False)
# mkt
model.fit(mkt_ret, mng_ret) # fit(X, y)
beta_mkt = model.coef_
name_mkt = data_mktbeta.columns.values
sortedidx = np.argsort(beta_mkt)
result_df.ix[idx, 'beta_mkt1'] = beta_mkt[sortedidx[-1]]
result_df.ix[idx, 'name_mkt1'] = name_mkt[sortedidx[-1]]
result_df.ix[idx, 'beta_mkt2'] = beta_mkt[sortedidx[-2]]
result_df.ix[idx, 'name_mkt2'] = name_mkt[sortedidx[-2]]
result_df.ix[idx, 'beta_mkt3'] = beta_mkt[sortedidx[-3]]
result_df.ix[idx, 'name_mkt3'] = name_mkt[sortedidx[-3]]
result_df.ix[idx, 'intercept_mkt'] = model.intercept_
result_df.ix[idx, 'score_mkt'] = model.score(mkt_ret, mng_ret)
# bias mkt
# calc ret
b_avg = np.mean(beta_mkt)
b_adj = beta_mkt - b_avg
ct = 1 / np.sum(b_adj[b_adj > 0]) # scale factor
b_adj = b_adj * ct
bias_retts_mkt = np.dot(mkt_ret, b_adj) # dot成个加权的收益率
temp = np.mean(bias_retts_mkt) * 250 # daily ret 的年化
if np.isnan(temp):
temp = 0
result_df.ix[idx, 'bias_ret_mkt'] = temp
temp = np.std(bias_retts_mkt) * 250**0.5 # daily ret std 的年化
if np.isnan(temp):
temp = 0
result_df.ix[idx, 'bias_var_mkt'] = temp
# calc score
# std coef
result_df.ix[idx, 'bias_score_mkt'] = np.std(beta_mkt)
# define indu model
model = linear_model.LassoCV(
positive=True,
cv=int(ob_win / 30), # subsample size = 30
selection='random',
fit_intercept=True,
normalize=False)
# indu
model.fit(indu_ret, mng_ret)
beta_indu = model.coef_
name_indu = data_indubeta.columns.values
sortedidx = np.argsort(beta_indu)
result_df.ix[idx, 'beta_indu1'] = beta_indu[sortedidx[-1]]
result_df.ix[idx, 'name_indu1'] = name_indu[sortedidx[-1]]
result_df.ix[idx, 'beta_indu2'] = beta_indu[sortedidx[-2]]
result_df.ix[idx, 'name_indu2'] = name_indu[sortedidx[-2]]
result_df.ix[idx, 'beta_indu3'] = beta_indu[sortedidx[-3]]
result_df.ix[idx, 'name_indu3'] = name_indu[sortedidx[-3]]
result_df.ix[idx, 'intercept_indu'] = model.intercept_
result_df.ix[idx,
'score_indu'] = model.score(indu_ret, mng_ret)
# bias indu
# calc ret
b_avg = np.mean(beta_indu)
b_adj = beta_indu - b_avg
ct = 1 / np.sum(b_adj[b_adj > 0]) # scale factor
b_adj = b_adj * ct
bias_retts_indu = np.dot(indu_ret, b_adj) # dot成个加权的收益率
temp = np.mean(bias_retts_indu) * 250 # daily ret 的年化
if np.isnan(temp):
temp = 0
result_df.ix[idx, 'bias_ret_indu'] = temp
temp = np.std(bias_retts_indu) * 250**0.5 # daily ret std 的年化
if np.isnan(temp):
temp = 0
result_df.ix[idx, 'bias_var_indu'] = temp
# calc score
# std coef
result_df.ix[idx, 'bias_score_indu'] = np.std(beta_indu)
# end of calc
idx += 1
# print('line:' + str(idx) + '/' + str(total) + ', done')
# end of while loop
# 截取starttime和endtime之间的result
sdtime = datetime.datetime.strptime(startdatestr, '%Y-%m-%d')
edtime = datetime.datetime.strptime(enddatestr, '%Y-%m-%d')
result_df = result_df[(result_df.EndDate >= sdtime)
& (result_df.EndDate <= edtime)]
# print(datetime.datetime.now())
print('End organize data of: ' + ManagerID)
return result_df
def computeRscores(product_features_list, product_ratings_list, num_features,
file_name):
from sklearn import linear_model
result = []
#创建一个文件夹
import os
new_file_dir = path + "data\\feature_coefficient_list_" + file_name.split(
".")[0] + "\\"
isExists = os.path.exists(new_file_dir)
if not isExists:
os.makedirs(new_file_dir)
new_file_name = new_file_dir + file_name.split(".")[0] + "_"
#第一种，直接利用linear regression
print "start to linear regression"
copy_product_features_list = copy.deepcopy(product_features_list)
copy_product_ratings_list = copy.deepcopy(product_ratings_list)
reg = linear_model.LinearRegression()
reg.fit(copy_product_features_list, copy_product_ratings_list)
del copy_product_features_list
del copy_product_ratings_list
file_path = new_file_name + "linear_regression_" + str(
num_features) + ".xls"
save_coefficients_new(reg.coef_, reg.intercept_, file_path)
copy_product_features_list = copy.deepcopy(product_features_list)
copy_product_ratings_list = copy.deepcopy(product_ratings_list)
r2_linearregression = reg.score(copy_product_features_list,
copy_product_ratings_list)
print "r2 score: ", r2_linearregression
del copy_product_features_list
del copy_product_ratings_list
#第二种，lasso
print "start to lasso regression"
copy_product_features_list = copy.deepcopy(product_features_list)
copy_product_ratings_list = copy.deepcopy(product_ratings_list)
reg = linear_model.LassoCV(cv=5, random_state=0)
reg.fit(copy_product_features_list, copy_product_ratings_list)
del copy_product_features_list
del copy_product_ratings_list
file_path = new_file_name + "linear_lassocv_regression_" + str(
num_features) + ".xls"
save_coefficients_new(reg.coef_, reg.intercept_, file_path)
copy_product_features_list = copy.deepcopy(product_features_list)
copy_product_ratings_list = copy.deepcopy(product_ratings_list)
r2_lasso = reg.score(copy_product_features_list, copy_product_ratings_list)
print "r2 score: ", r2_lasso
del copy_product_features_list
del copy_product_ratings_list
result = reg.coef_
#第三种 ridge
print "start to ridge regression"
copy_product_features_list = copy.deepcopy(product_features_list)
copy_product_ratings_list = copy.deepcopy(product_ratings_list)
reg = linear_model.RidgeCV(cv=5)
reg.fit(copy_product_features_list, copy_product_ratings_list)
del copy_product_features_list
del copy_product_ratings_list
file_path = new_file_name + "linear_ridge_regression_" + str(
num_features) + ".xls"
save_coefficients_new(reg.coef_, reg.intercept_, file_path)
copy_product_features_list = copy.deepcopy(product_features_list)
copy_product_ratings_list = copy.deepcopy(product_ratings_list)
r2_ridge = reg.score(copy_product_features_list, copy_product_ratings_list)
print "r2 score: ", r2_ridge
del copy_product_features_list
del copy_product_ratings_list
return result
#%%
import sklearn.linear_model as sk_lm
import sklearn.ensemble as sk_ens
import xgboost as xgb
import sklearn.neural_network as sk_nn
from sklearn.metrics import r2_score
from sklearn.model_selection import StratifiedKFold, KFold
df_X_train = df_non_obj_feats[:train_len]
df_X_test = df_non_obj_feats[train_len:]
y = target_log1p
df_importance = pd.DataFrame(data=None, index=df_non_obj_feats.columns)
#%%
model_lasso = sk_lm.LassoCV(alphas=[3e-4, 3e-3, 3e-2, 3e-1, 3, 30])
model_lasso.fit(df_X_train, y)
model_lasso.score(df_X_train, y)
r2_score_lasso = r2_score(y, model_lasso.predict(df_X_train))
print('r2_score of Lasso:', r2_score_lasso)
lasso_importance = pd.DataFrame(model_lasso.coef_,
df_X_train.columns,['LS_feat_importance'])
lasso_importance.plot(); plt.show()
df_importance['LassoCV'] = r2_score_lasso*lasso_importance/np.max(np.abs(lasso_importance))
#%%
model_elen = sk_lm.ElasticNetCV(alphas=[3e-4, 3e-3, 3e-2, 3e-1, 3, 30])
model_elen.fit(df_X_train, y)
model_elen.score(df_X_train, y)
r2_score_elen = r2_score(y, model_elen.predict(df_X_train))
print('r2_score of ElasticNet:', r2_score_elen)
def main():
pd.set_option('display.max_columns', None)
from sklearn.neighbors import KNeighborsClassifier
data = pd.read_csv('Life Expectancy Data.csv')
# print(data.columns)
data.rename(columns={'Life expectancy ': "Life_expectancy"}, inplace=True)
data.rename(columns={'Adult Mortality': "Adult_Mortality"}, inplace=True)
data.rename(columns={'infant deaths': "infant_deaths"}, inplace=True)
data.rename(columns={'percentage expenditure': 'percentage_expenditure'}, inplace=True)
data.rename(columns={'Hepatitis B': "Hepatitis_B"}, inplace=True)
data.rename(columns={' BMI ': "BMI"}, inplace=True)
data.rename(columns={'under-five deaths ': "under-five_deaths"}, inplace=True)
data.rename(columns={'Total expenditure': "Total_expenditure"}, inplace=True)
data.rename(columns={' HIV/AIDS': "HIV/AIDS"}, inplace=True)
data.rename(columns={' thinness 1-19 years': "thinness_1-19_years"}, inplace=True)
data.rename(columns={' thinness 5-9 years': "thinness_5-9_years"}, inplace=True)
data.rename(columns={'Income composition of resources': "Income_composition_of_resources"}, inplace=True)
data.rename(columns={'HIV/AIDS': "HIV_AIDS"}, inplace=True)
data.rename(columns={'Measles ': "Measles"}, inplace=True)
data.rename(columns={'Diphtheria ': "Diphtheria"}, inplace=True)
# delet the data with null life expectancy value
data['Life_expectancy'] = data['Life_expectancy'].fillna(999)
drop_index = data[(data.Life_expectancy == 999)].index.tolist()
data = data.drop(drop_index)
# print(data['Life_expectancy'])
# make life_expectancy as our output
labels = data.loc[:, ['Life_expectancy']]
# del data['Life_expectancy']
# deal with categorical data "status" since it contains numerical quality
data['Status'] = data['Status'].str.replace('Developed', '2', case=False)
data['Status'] = data['Status'].str.replace('Developing', '1', case=False)
# print('data=',data)
# data=pd.get_dummies(data, prefix=['Country'], columns=['Country'])
# print('size after dummy', data.shape)
# Separate the data to train, val and test data
x, x_test, y, y_test = train_test_split(data, labels, test_size=0.2, train_size=0.8, random_state=1)
x_train, x_val, y_train, y_val = train_test_split(x, y, test_size=0.2, train_size=0.8, random_state=50)
# print(x_train)
# calculate the null value in each column
NoNull_train = x_train.isnull().sum(axis=0)
# print('--------Null data in train----------')
# print(NoNull_train)
# print('--------Null data in train----------')
'''
sns.distplot(y_train['Life_expectancy'])
mu=y_train['Life_expectancy'].mean()
sigma=y_train['Life_expectancy'].std()
#Now plot the distribution
plt.legend(['Original dist. ($\mu=$ {:.2f} and $\sigma=$ {:.2f} )'.format(mu, sigma)],loc='best')
plt.ylabel('Frequency')
plt.title('Life_expectancy')
#Get also the QQ-plot
fig = plt.figure()
res = stats.probplot(y_train['Life_expectancy'], plot=plt)
plt.show()
'''
# make the target_train data become more closed to the normal distribution
# ----------------------------------------------
# We use the numpy fuction log1p which applies log(1+x) to all elements of the column
'''
#Check the new distribution
sns.distplot(y_train['Life_expectancy'] , fit=norm);
# Get the fitted parameters used by the function
(mu, sigma) = norm.fit(y_train['Life_expectancy'])
print( '\n mu = {:.2f} and sigma = {:.2f}\n'.format(mu, sigma))
#Now plot the distribution
plt.legend(['Normal dist. ($\mu=$ {:.2f} and $\sigma=$ {:.2f} )'.format(mu, sigma)],loc='best')
plt.ylabel('Frequency')
plt.title('Life Expectancy')
#Get also the QQ-plot
fig = plt.figure()
res = stats.probplot(y_train['Life_expectancy'], plot=plt)
plt.show()
'''
Null_train_ratio = (x_train.isnull().sum() / len(x_train)) * 100
Null_train_ratio = Null_train_ratio.sort_values(ascending=False)
AllNull_train_ratio = Null_train_ratio.drop(Null_train_ratio[Null_train_ratio == 0].index)
missing_train_ratio = pd.DataFrame({'Missing train data ratio': AllNull_train_ratio})
# print(missing_train_ratio)
f, ax = plt.subplots(figsize=(15, 12))
plt.xticks(rotation='90') # ratate direction of words for each feature
sns.barplot(x=Null_train_ratio.index, y=Null_train_ratio)
plt.xlabel('Features', fontsize=15)
plt.ylabel('Percent of missing values', fontsize=15)
plt.title('missing data percentage by feature', fontsize=15)
plt.show()
# print("--------------train data description-------------")
# print(x_train.describe())
# draw to recognize the outliers
# Show the boxplot before dealing with outliers
# feature "Adult_Mortality"
# showplot(x_train,'before')
# try to remove the outliers
# print('len of x train=',len(x_train))
Q1 = x_train.quantile(0.25)
Q3 = x_train.quantile(0.75)
IQR = Q3 - Q1
x_train = outlier_remove_traindata(x_train, Q1, Q3, IQR)
x_val = outlier_remove_traindata(x_val, Q1, Q3, IQR)
# print('finish removing the outliers')
# ----------finished dealing with the outlier in each features-------------
# Show the boxplot after dealing with outliers
# feature "Adult_Mortality"
# showplot(x_train,'after')
####fill the missing data with mean value
x_train = x_train.fillna(x_train.mean())
x_val = x_val.fillna(x_train.mean())
x = x.fillna(x.mean())
x_test = x_test.fillna(x.mean())
####fill the missing data with median
# x_train=x_train.fillna(x_train.median())
# x_val=x_val.fillna(x_train.median())
####fill the missing data with -1
# x_train=x_train.fillna(-1)
# x_val=x_val.fillna(-1)
####fill the missing data with 0
# x_train=x_train.fillna(0)
# x_val=x_val.fillna(0)
NoNull_train = x_train.isnull().sum(axis=0)
# print('--------Null data in train----------')
# print('NoNull_train',NoNull_train)
# separate the string and numerical data
x_train_str = x_train.loc[:, ["Country"]]
x_train_num = x_train.loc[:, ['Year', 'Status', 'Life_expectancy', 'Adult_Mortality', 'infant_deaths', 'Alcohol',
'percentage_expenditure', 'Hepatitis_B', 'Measles', 'BMI', 'under-five_deaths',
'Polio', 'Total_expenditure', 'Diphtheria', 'HIV_AIDS', 'GDP', 'Population',
'thinness_1-19_years', 'thinness_5-9_years', 'Income_composition_of_resources',
'Schooling']]
x_val_str = x_val.loc[:, ["Country"]]
x_val_num = x_val.loc[:, ['Year', 'Status', 'Life_expectancy', 'Adult_Mortality', 'infant_deaths', 'Alcohol',
'percentage_expenditure', 'Hepatitis_B', 'Measles', 'BMI', 'under-five_deaths', 'Polio',
'Total_expenditure', 'Diphtheria', 'HIV_AIDS', 'GDP', 'Population', 'thinness_1-19_years',
'thinness_5-9_years', 'Income_composition_of_resources', 'Schooling']]
x_str = x.loc[:, ["Country"]]
x_num = x.loc[:, ['Year', 'Status', 'Life_expectancy', 'Adult_Mortality', 'infant_deaths', 'Alcohol',
'percentage_expenditure', 'Hepatitis_B', 'Measles', 'BMI', 'under-five_deaths', 'Polio',
'Total_expenditure', 'Diphtheria', 'HIV_AIDS', 'GDP', 'Population', 'thinness_1-19_years',
'thinness_5-9_years', 'Income_composition_of_resources', 'Schooling']]
x_test_num = x_test.loc[:, ['Year', 'Status', 'Life_expectancy', 'Adult_Mortality', 'infant_deaths', 'Alcohol',
'percentage_expenditure', 'Hepatitis_B', 'Measles', 'BMI', 'under-five_deaths', 'Polio',
'Total_expenditure', 'Diphtheria', 'HIV_AIDS', 'GDP', 'Population',
'thinness_1-19_years', 'thinness_5-9_years', 'Income_composition_of_resources',
'Schooling']]
x_train_str = pd.get_dummies(x_train_str)
# Try to see the correlation between country(after get dummy) and life expectancy
country_col = x_train_str.columns
# print('country column =',len(country_col))
# Try to see the correlation between country(after get dummy) and life expectancy
x_train_str["Life_expectancy"] = y_train
country_corrmat = x_train_str.corr()
cols = abs(country_corrmat).nlargest(10, 'Life_expectancy')['Life_expectancy'].index
cm = np.corrcoef(x_train_str[cols].values.T)
sns.set(font_scale=1.25)
plt.subplots(figsize=(15, 12))
hm = sns.heatmap(cm, cbar=True, annot=True, square=True, fmt='.2f', annot_kws={'size': 10}, yticklabels=cols.values,
xticklabels=cols.values)
bottom, top = hm.get_ylim()
hm.set_ylim(bottom + 0.5, top - 0.5)
plt.title('The country that is most related to life expectancy')
plt.show()
# Since the highest correlation between country and life expectancy is 0.17, we decide not to use the feature "country"
# standardize the data
standar = preprocessing.StandardScaler().fit(x_train_num)
x_train = standar.transform(x_train_num)
x_val = standar.transform(x_val_num)
x_train1 = pd.DataFrame(data=x_train, columns=x_train_num.columns)
x_val1 = pd.DataFrame(data=x_val, columns=x_train_num.columns)
# Correlation map to see how features are correlated with LifeExpectancy
corrmat = x_train1.corr()
plt.subplots(figsize=(18, 15))
ax = sns.heatmap(corrmat, vmax=1, annot=True, square=True, vmin=0)
bottom, top = ax.get_ylim()
ax.set_ylim(bottom + 0.5, top - 0.5)
plt.title('Correlation Heatmap Between Each Feature')
plt.show()
cols = abs(corrmat).nlargest(19, 'Life_expectancy')['Life_expectancy'].index
cm = np.corrcoef(x_train1[cols].values.T)
sns.set(font_scale=1.25)
plt.subplots(figsize=(15, 12))
plt.title('18 Features that are most related to Life Expectancy')
hm = sns.heatmap(cm, cbar=True, annot=True, square=True, fmt='.2f', annot_kws={'size': 10}, yticklabels=cols.values,
xticklabels=cols.values)
bottom, top = hm.get_ylim()
hm.set_ylim(bottom + 0.5, top - 0.5)
plt.show()
cols = abs(corrmat).nlargest(21, 'Life_expectancy')['Life_expectancy'].index
related_col = cols.drop(['Life_expectancy']).drop(['Status']).drop(['Hepatitis_B']).drop(['infant_deaths']).drop(
['GDP']).drop(['Measles']).drop(['Population']).drop(['percentage_expenditure']).drop(['Diphtheria'])
# related_col = related_col.drop(['Status'])
# related_col = related_col.drop(['under-five_deaths'])
# print("The columns most related to Life expectancy=", related_col)
# transform the test data
standar_all = preprocessing.StandardScaler().fit(x_num)
x = standar_all.transform(x_num)
x_test = standar_all.transform(x_test_num)
x1 = pd.DataFrame(data=x, columns=x_train_num.columns)
x_test1 = pd.DataFrame(data=x_test, columns=x_train_num.columns)
x_train = x_train1[related_col]
x_val = x_val1[related_col]
x = x1[related_col]
x_test = x_test1[related_col]
'''
# Choose the optimal no of features => 18 features (k=19, we need to deduct 'life expectancy')
meanerror_NoFeature_val = []
mse_NoFeature_val = []
for k in range(5, 21):
cols = abs(corrmat).nlargest(k, 'Life_expectancy')['Life_expectancy'].index
related_col = cols.drop(['Life_expectancy'])
x_train = x_train1[related_col]
x_val = x_val1[related_col]
mean_train = np.mean(y_train)
mean_train_array = [x * mean_train for x in np.ones(y_train.shape[0])]
np.ones(y_train.shape)
# We found that the min MSE happened when n_estimators=25
error_train = []
error_val = []
mse_train = []
mse_val = []
for j in range(10):
pre_train, pre_X_train_pick, pre_y_train, pre_y_train_pick = train_test_split(x_train, y_train,
test_size=1 / 3)
RF = RandomForestRegressor(n_estimators=25, bootstrap=True, max_features=3)
RF.fit(pre_X_train_pick, pre_y_train_pick.values.ravel())
predict_train = RF.predict(x_train)
predict_val = RF.predict(x_val)
acc_train = RF.score(x_train, y_train)
acc_val = RF.score(x_val, y_val)
error_train = np.append(error_train, 1 - acc_train)
error_val = np.append(error_val, 1 - acc_val)
mse_train = np.append(mse_train, mean_squared_error(predict_train, y_train))
mse_val = np.append(mse_val, mean_squared_error(predict_val, y_val))
meanerror_val = np.mean(error_val)
mean_mse_val = np.mean(mse_val)
meanerror_NoFeature_val = np.append(meanerror_NoFeature_val, meanerror_val)
mse_NoFeature_val = np.append(mse_NoFeature_val, mean_mse_val)
# print('mean error in validation set when 4~19 features')
# print(meanerror_NoFeature_val)
# print(' ')
# print('mse in validation set when 4~19 features')
# print(mse_NoFeature_val)
print('When we set the number of features from 4-19,')
print('min mean error = %.2f and min MSE = %.2f in validation set when we chose %.0f correlated features' % (
min(meanerror_NoFeature_val), min(mse_NoFeature_val), np.argmin(meanerror_NoFeature_val) + 4))
X = np.arange(4, 20)
plt.plot(X, meanerror_NoFeature_val, label='Mean Error')
plt.title('Number of Features vs Mean Error')
plt.ylabel('Mean Error')
plt.xlabel('Number of features')
plt.show()
plt.plot(X, mse_NoFeature_val, label='MSE')
plt.title('Number of features vs MSE')
plt.ylabel('MSE')
plt.xlabel('Number of features')
plt.show()
'''
################Regression Tree#########################
# Find the best way to fill the missing data
print('###################Random Forest Regression########################')
meanerror_train = []
meanerror_val = []
mean_mse_train = []
mean_mse_val = []
for i in range(50):
error_train = []
error_val = []
mse_train = []
mse_val = []
for j in range(10):
pre_train, pre_X_train_pick, pre_y_train, pre_y_train_pick = train_test_split(x_train, y_train,
test_size=1 / 3)
RF = RandomForestRegressor(n_estimators=i + 1, bootstrap=True, random_state=0)
RF.fit(pre_X_train_pick, pre_y_train_pick.values.ravel())
predict_train = RF.predict(x_train)
predict_val = RF.predict(x_val)
acc_train = RF.score(x_train, y_train)
acc_val = RF.score(x_val, y_val)
error_train = np.append(error_train, 1 - acc_train)
error_val = np.append(error_val, 1 - acc_val)
mse_train = np.append(mse_train, mean_squared_error(predict_train, y_train))
mse_val = np.append(mse_val, mean_squared_error(predict_val, y_val))
meanerror_train = np.append(meanerror_train, np.mean(error_train))
meanerror_val = np.append(meanerror_val, np.mean(error_val))
mean_mse_train = np.append(mean_mse_train, np.mean(mse_train))
mean_mse_val = np.append(mean_mse_val, np.mean(mse_val))
# print('When fill the missing data with mean:')
# print('mean error in training set =', meanerror_train)
# print('mean error in validation set =', meanerror_val)
# print('MSE in training set =',mean_mse_train)
# print('MSE in validation set =',mean_mse_val)
print("we got the min MSE value=%.3f and error rate=%.3f in validation set when there are %.0f trees" % (
min(mean_mse_val), min(meanerror_val), np.argmin(mean_mse_val) + 1))
fi = pd.DataFrame({'feature': list(x_train.columns),
'importance': RF.feature_importances_}). \
sort_values('importance', ascending=False)
#print('importance=', fi)
# plot the figure
X = np.arange(1, 51)
fig, (ax1, ax2) = plt.subplots(nrows=2, ncols=1)
fig.suptitle('Random Forest Regression')
ax1.plot(X, meanerror_train, label='train data')
ax1.plot(X, meanerror_val, color='r', label='val data')
ax1.set_ylabel('Error Rate')
ax1.plot(np.argmin(meanerror_val) + 1, min(meanerror_val), '*', label='minimum', color='b', markersize=15)
ax1.legend(loc='best')
ax2.plot(X, mean_mse_train, label='train data')
ax2.plot(X, mean_mse_val, color='r', label='val data')
ax2.set_ylabel('MSE')
ax2.set_xlabel('Number of trees')
ax2.plot(np.argmin(mean_mse_val) + 1, min(mean_mse_val), '*', label='minimum', color='b', markersize=15)
ax2.legend(loc='best')
plt.show()
'''
#We found that the min MSE happened when n_estimators=25
error_train = []
error_val = []
mse_train = []
mse_val = []
for j in range(10):
pre_train, pre_X_train_pick, pre_y_train, pre_y_train_pick = train_test_split(x_train, y_train, test_size=1 / 3)
RF = RandomForestRegressor(n_estimators=25, bootstrap=True, max_features=3)
RF.fit(pre_X_train_pick, pre_y_train_pick.values.ravel())
predict_train = RF.predict(x_train)
predict_val = RF.predict(x_val)
acc_train = RF.score(x_train, y_train)
acc_val = RF.score(x_val, y_val)
error_train = np.append(error_train, 1 - acc_train)
error_val = np.append(error_val, 1 - acc_val)
mse_train = np.append(mse_train, mean_squared_error(predict_train, y_train))
mse_val = np.append(mse_val, mean_squared_error(predict_val, y_val))
meanerror_train = np.mean(error_train)
meanerror_val = np.mean(error_val)
mean_mse_train = np.mean(mse_train)
mean_mse_val = np.mean(mse_val)
print('When fill the missing data with 0 and n_estimator = 25:')
print('mean error in training set =', meanerror_train)
print('mean error in validation set =', meanerror_val)
print('MSE in training set =',mean_mse_train)
print('MSE in validation set =',mean_mse_val)
'''
#############Linear Regression################
# linear regression (general)
print('###################linear regression (general)########################')
lin_mse_val = []
lin_error_val = []
lin_mse_train = []
lin_error_train = []
corrmat = x_train1.corr()
for k in range(5, 21):
cols = abs(corrmat).nlargest(k, 'Life_expectancy')['Life_expectancy'].index
related_col = cols.drop(['Life_expectancy'])
x_train = x_train1[related_col]
x_val = x_val1[related_col]
reg = linear_model.LinearRegression()
reg.fit(x_train, y_train)
reg_predict_val = reg.predict(x_val)
reg_predict_train = reg.predict(x_train)
reg_acc_val = reg.score(x_val, y_val)
reg_acc_train = reg.score(x_train, y_train)
lin_mse_val = np.append(lin_mse_val, mean_squared_error(y_val, reg_predict_val))
lin_mse_train = np.append(lin_mse_train, mean_squared_error(y_train, reg_predict_train))
lin_error_val = np.append(lin_error_val, 1 - reg_acc_val)
lin_error_train = np.append(lin_error_train, 1 - reg_acc_train)
print('Linear regression when featrues=4-19')
# print('error rate in validation set =')
# print(lin_error_val)
# print('MSE in validation set')
# print(lin_mse_val)
print('We can find the min error rate= %.4f and min MSE= %.4f when there are %.0f features' % (
min(lin_error_val), min(lin_mse_val), np.argmin(lin_mse_val) + 4))
X = np.arange(4, 20, 1)
fig, (ax1, ax2) = plt.subplots(nrows=2, ncols=1)
fig.suptitle('Linear Regression')
ax1.plot(X, lin_error_val, color='r', label='Validation set')
ax1.plot(X, lin_error_train, label='Training set')
ax1.set_ylabel('Error Rate')
ax1.plot(np.argmin(lin_error_val) + 4, min(lin_error_val), '*', label='minimum', color='b', markersize=15)
ax1.legend(loc='best')
ax2.plot(X, lin_mse_val, color='r', label='Validation set')
ax2.plot(X, lin_mse_train, label='Training set')
ax2.set_ylabel('MSE')
ax2.set_xlabel('Number of Features')
ax2.plot(np.argmin(lin_mse_val) + 4, min(lin_mse_val), '*', label='minimum', color='b', markersize=15)
ax2.legend(loc='best')
plt.show()
############Ridge Regression###############
print('##############Ridge Regression(without CV)###############')
X = np.linspace(-3, 1, 30)
cols = abs(corrmat).nlargest(19, 'Life_expectancy')[
'Life_expectancy'].index # Select 7 features that are the most related to life expectancy
related_col = cols.drop(['Life_expectancy'])
x_train = x_train1[related_col]
x_val = x_val1[related_col]
rid_mse_val = []
rid_mse_train = []
rid_error_val = []
rid_error_train = []
for i in X:
ridge = linear_model.Ridge(alpha=10 ** i, normalize=True)
ridge.fit(x_train, y_train)
ridge_predict_val = ridge.predict(x_val)
ridge_predict_train = ridge.predict(x_train)
ridge_acc_val = ridge.score(x_val, y_val)
ridge_acc_train = ridge.score(x_train, y_train)
rid_mse_val = np.append(rid_mse_val, mean_squared_error(y_val, ridge_predict_val))
rid_mse_train = np.append(rid_mse_train, mean_squared_error(y_train, ridge_predict_train))
rid_error_val = np.append(rid_error_val, 1 - ridge_acc_val)
rid_error_train = np.append(rid_error_train, 1 - ridge_acc_train)
# print('error rate in validation set =')
# print(rid_error_val)
# print('MSE in validation set')
# print(rid_mse_val)
print('We can find the min error rate= %.4f and min MSE= %.4f when alpha= %.6f ' % (
min(rid_error_val), min(rid_mse_val), 10 ** X[np.argmin(rid_mse_val)]))
# print('alpha=',X)
fig, (ax1, ax2) = plt.subplots(nrows=2, ncols=1)
fig.suptitle('Ridge Regression (Without CV)')
ax1.plot(X, rid_error_train, label='Training set')
ax1.plot(X, rid_error_val, color='r', label='Validation set')
ax1.set_ylabel('Error Rate')
ax1.set_xlabel('log(alpha)')
ax1.plot(X[np.argmin(rid_error_val)], min(rid_error_val), '*', label='minimum', color='b', markersize=15)
ax1.legend(loc='best')
ax2.plot(X, rid_mse_train, label='Training set')
ax2.plot(X, rid_mse_val, color='r', label='Validation set')
ax2.set_ylabel('MSE')
ax2.set_xlabel('log(alpha)')
ax2.plot(X[np.argmin(rid_mse_val)], min(rid_mse_val), '*', label='minimum', color='b', markersize=15)
ax2.legend(loc='best')
plt.show()
print('##############Ridge Regression(with CV)###############')
X = np.linspace(-3, 1, 30)
cols = abs(corrmat).nlargest(19, 'Life_expectancy')[
'Life_expectancy'].index # Select 7 features that are the most related to life expectancy
related_col = cols.drop(['Life_expectancy']).drop(['Status'])
#print('in ridge regression')
#print('related col=', related_col)
xx = x1[related_col]
ridCV_err = np.zeros([len(X), 6])
ridCV_mse = np.zeros([len(X), 6])
for i in range(5, 11): # column
kfold = KFold(n_splits=i, shuffle=True)
for j in range(len(X)): # row
ridgeCV = linear_model.RidgeCV(alphas=10 ** X, normalize=True)
ridCV_neg_mse = cross_val_score(ridgeCV, xx, y, cv=kfold, scoring='neg_mean_squared_error')
ridCV_score = cross_val_score(ridgeCV, xx, y, cv=kfold, scoring='r2')
# ridCV_err[j][i-5] = 1- np.mean(ridCV_score)
ridCV_mse[j][i - 5] = np.mean(ridCV_neg_mse) * (-1)
min_err_index = np.unravel_index(ridCV_err.argmin(), ridCV_err.shape)
min_mse_index = np.unravel_index(ridCV_mse.argmin(), ridCV_mse.shape)
print('When we use Ridge Regression with cross validation')
print('We got the min MSE value= %.3f when we applied %.0f fold and alpha = %.5f' % (
ridCV_mse.min(), min_mse_index[1] + 5, 10 ** X[min_mse_index[0]]))
print('')
bestK_alpha_mse = ridCV_mse[:, min_mse_index[1]].reshape((ridCV_mse[:, min_mse_index[1]].shape[0], 1))
# bestK_alpha_err = ridCV_err[:,min_err_index[1]].reshape((ridCV_err[:,min_err_index[1]].shape[0],1))
fig, ax2 = plt.subplots(nrows=1, ncols=1)
fig.suptitle('Ridge Regression (With CV when K= %.0f)' % (min_mse_index[1] + 5))
# ax1.plot(X, bestK_alpha_err)
ax1.set_ylabel('Error Rate')
ax1.set_xlabel('log(alpha)')
# ax1.plot(X[min_err_index[0]],bestK_alpha_err.min(),'*', label='minimum',color='b',markersize=15)
ax1.legend(loc='best')
ax2.plot(X, bestK_alpha_mse)
ax2.set_ylabel('MSE')
ax2.set_xlabel('log(alpha)')
ax2.plot(X[min_mse_index[0]], bestK_alpha_mse.min(), '*', label='minimum', color='b', markersize=15)
ax2.legend(loc='best')
# plt.show()
###########Lasso Regression###############
print('##############Lasso Regression(without CV)###############')
X = np.linspace(-3, 1, 30)
x_train = x_train1[related_col]
x_val = x_val1[related_col]
lasso_mse_val = []
lasso_mse_train = []
lasso_error_val = []
lasso_error_train = []
for i in X:
lasso = linear_model.Lasso(alpha=10 ** i, normalize=True)
lasso.fit(x_train, y_train)
lasso_predict_val = lasso.predict(x_val)
lasso_predict_train = lasso.predict(x_train)
lasso_acc_val = lasso.score(x_val, y_val)
lasso_acc_train = lasso.score(x_train, y_train)
lasso_mse_val = np.append(lasso_mse_val, mean_squared_error(y_val, lasso_predict_val))
lasso_mse_train = np.append(lasso_mse_train, mean_squared_error(y_train, lasso_predict_train))
lasso_error_val = np.append(lasso_error_val, 1 - lasso_acc_val)
lasso_error_train = np.append(lasso_error_train, 1 - lasso_acc_train)
# print('error rate in validation set =')
# print(lasso_error_val)
# print('MSE in validation set')
# print(lasso_mse_val)
print('We can find the min error rate= %.4f and min MSE= %.4f when alpha= %.6f ' % (
min(lasso_error_val), min(lasso_mse_val), 10 ** X[np.argmin(lasso_mse_val)]))
fig, (ax1, ax2) = plt.subplots(nrows=2, ncols=1)
fig.suptitle('Lasso Regression (Without CV)')
ax1.plot(X, lasso_error_train, label='Training set')
ax1.plot(X, lasso_error_val, color='r', label='Validation set')
ax1.set_ylabel('Error Rate')
ax1.plot(X[np.argmin(lasso_error_val)], min(lasso_error_val), '*', label='minimum', color='b', markersize=15)
ax1.legend(loc='lower right')
ax2.plot(X, lasso_mse_train, label='Training set')
ax2.plot(X, lasso_mse_val, color='r', label='Validation set')
ax2.set_ylabel('MSE')
ax2.set_xlabel('log(alpha)')
ax2.plot(X[np.argmin(lasso_mse_val)], min(lasso_mse_val), '*', label='minimum', color='b', markersize=15)
plt.show()
print('##############Lasso Regression(with CV)###############')
X = np.linspace(-3, 1, 30)
xx = x1[related_col]
lassoCV_err = np.zeros([len(X), 6])
lassoCV_mse = np.zeros([len(X), 6])
for i in range(5, 11): # column
kfold = KFold(n_splits=i, shuffle=True)
for j in range(len(X)): # row
lassoCV = linear_model.LassoCV(alphas=10 ** X, normalize=True)
lassoCV_neg_mse = cross_val_score(lassoCV, xx, y, cv=kfold, scoring='neg_mean_squared_error')
lassoCV_score = cross_val_score(lassoCV, xx, y, cv=kfold, scoring='r2')
# lassoCV_err[j][i-5] = 1- np.mean(lassoCV_score)
lassoCV_mse[j][i - 5] = np.mean(lassoCV_neg_mse) * (-1)
# min_err_index=np.unravel_index(lassoCV_err.argmin(), lassoCV_err.shape)
min_mse_index = np.unravel_index(lassoCV_mse.argmin(), lassoCV_mse.shape)
print('When we use Lasso Regression with cross validation')
print('We got the min MSE value= %.3f when we applied %.0f fold and alpha = %.5f' % (
lassoCV_mse.min(), min_mse_index[1] + 5, 10 ** X[min_mse_index[0]]))
bestK_alpha_mse = lassoCV_mse[:, min_mse_index[1]].reshape((lassoCV_mse[:, min_mse_index[1]].shape[0], 1))
# bestK_alpha_err = lassoCV_err[:,min_err_index[1]].reshape((lassoCV_err[:,min_err_index[1]].shape[0],1))
fig, ax2 = plt.subplots(nrows=1, ncols=1)
fig.suptitle('Lasso Regression (With CV when K= %.0f)' % (min_mse_index[1] + 5))
# ax1.plot(X, bestK_alpha_err)
ax1.set_ylabel('Error Rate')
ax1.set_xlabel('log(alpha)')
# ax1.plot(X[min_err_index[0]],bestK_alpha_err.min(),'*', label='minimum',color='b',markersize=15)
ax1.legend(loc='best')
ax2.plot(X, bestK_alpha_mse)
ax2.set_ylabel('MSE')
ax2.set_xlabel('log(alpha)')
ax2.plot(X[min_mse_index[0]], bestK_alpha_mse.min(), '*', label='minimum', color='b', markersize=15)
ax2.legend(loc='best')
# plt.show()
avg_ytest = np.mean(y_test)
one_array = np.ones([len(y_test), 1])
mean_arr = avg_ytest['Life_expectancy'] * one_array
baseline_mse = mean_squared_error(y_test, mean_arr)
baseline_err = 1 - r2_score(y_test, mean_arr)
print('Number of training data (original):', len(y))
print('Number of test data:', len(y_test))
print('Number of training data (New):', len(y_train))
print('Number of validation data:', len(y_val))
print('###################Final model: Random Forest Regression########################')
cols = abs(corrmat).nlargest(21, 'Life_expectancy')['Life_expectancy'].index
related_col = cols.drop(['Life_expectancy']).drop(['Status']).drop(['Hepatitis_B']).drop(['infant_deaths']).drop(
['GDP']).drop(['Measles']).drop(['Population']).drop(['percentage_expenditure']).drop(['Diphtheria'])
error_x = []
error_test = []
mse_x = []
mse_test = []
oob_error = []
for j in range(10):
pre_train, pre_X_train_pick, pre_y_train, pre_y_train_pick = train_test_split(x, y, test_size=1 / 3)
RF = RandomForestRegressor(n_estimators=38, bootstrap=True, random_state=0, oob_score=True)
RF.fit(pre_X_train_pick, pre_y_train_pick.values.ravel())
predict_x = RF.predict(x)
predict_test = RF.predict(x_test)
acc_x = RF.score(x, y)
acc_test = RF.score(x_test, y_test)
error_x = np.append(error_x, 1 - acc_x)
error_test = np.append(error_test, 1 - acc_test)
oob_error = np.append(oob_error, 1 - RF.oob_score_)
mse_x = np.append(mse_x, mean_squared_error(predict_x, y))
mse_test = np.append(mse_test, mean_squared_error(predict_test, y_test))
mean_oob_err = np.mean(oob_error)
meanerror_x = np.mean(error_x)
meanerror_test = np.mean(error_test)
mean_mse_x = np.mean(mse_x)
mean_mse_test = np.mean(mse_test)
var_mse_test = np.var(mse_test)
var_err_test = np.var(error_test)
print('In our final model (38 trees):')
print('In the whole training data')
print('Mean MSE =', mean_mse_x)
print('Mean Error Rate =', meanerror_x)
print('In the test data')
print('Mean MSE = %.3f with variance = %.3f ' % (mean_mse_test, var_mse_test))
print('Mean Error Rate = %.5f with variance = %.5f ' % (meanerror_test, var_err_test))
print('Out Of Sample Error = ', mean_oob_err)
print('####################Baseline######################')
print('The baseline for the test data:')
print('MSE = ', baseline_mse)
print('Error Rate=', baseline_err)
#Draw the 2D plot
feature = ['HIV_AIDS', 'Income_composition_of_resources', 'Adult_Mortality', 'Schooling']
for i in feature:
for j in range(10):
pre_train, pre_X_train_pick, pre_y_train, pre_y_train_pick = train_test_split(x, y, test_size=1 / 3)
RF = RandomForestRegressor(n_estimators=38, bootstrap=True, random_state=0)
RF.fit(pre_X_train_pick[[i]], pre_y_train_pick.values.ravel())
predict_x = RF.predict(x[[i]])
predict_test = RF.predict(x_test[[i]])
X_grid = np.arange(min(x[i]), max(x[i]), 0.001)
# reshape for reshaping the data into a len(X_grid)*1 array,
# i.e. to make a column out of the X_grid value
X_grid = X_grid.reshape((len(X_grid), 1))
# Scatter plot for original data
plt.scatter(x[i], y, color='blue', label='training data points')
# plot predicted data
plt.plot(X_grid, RF.predict(X_grid), color='green', label='regression function')
plt.title('Random Forest Regression')
plt.xlabel(i)
plt.ylabel('Life expectancy')
plt.legend(loc='best')
plt.show()
pylab.ylabel("Ridge_error_Tst")
pylab.figure(4)
pylab.plot([0, 0.1, 1, 10, 100, 1000], lasso_error_Tst)
pylab.xlabel("lambda")
pylab.ylabel("lasso_error_Tst")
pylab.show()
# running Cross Validation for Ridge and lasso and extracting the best fitted lambda/alpha
R_Trn = linear_model.RidgeCV(fit_intercept=False, cv=5)
Ridge_Trn = R_Trn.fit(var_Trn, price_Trn)
Ridge_Trn.alpha = Ridge_Trn.alpha_
print "The best alpha for Ridge_train is: \n", Ridge_Trn.alpha, "\n"
l_Trn = linear_model.LassoCV(fit_intercept=False, cv=5)
lasso_Trn = l_Trn.fit(var_Trn, price_Trn)
lasso_Trn.alpha = lasso_Trn.alpha_
print "The best alpha for lasso_train is: \n", lasso_Trn.alpha, "\n"
# extracting the w using the best fitted lambda for both Ridge and lasso
R_Trn = linear_model.Ridge(alpha=Ridge_Trn.alpha, fit_intercept=False)
Ridge_Trn = R_Trn.fit(var_Trn, price_Trn)
print "The best fitted coefs for Ridge_train is: \n", Ridge_Trn.coef_, "\n"
l_Trn = linear_model.Lasso(alpha=lasso_Trn.alpha, fit_intercept=False)
lasso_Trn = l_Trn.fit(var_Trn, price_Trn)
print "The best fitted coefs for lasso_train is: \n", lasso_Trn.coef_, "\n"
# fitting obtained model to test dataset and mesuring errors
R_Tst = linear_model.Ridge(alpha=Ridge_Trn.alpha, fit_intercept=False)
def regression(XTrain, betaTrain, XTest):
model = linear_model.LassoCV(
cv=10, alphas=[0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1, 5, 10])
model.fit(XTrain, betaTrain)
Beta = model.predict(XTest)
return [i for i in Beta]
def model_selection():
# This is to avoid division by zero while doing np.log10
EPSILON = 1e-5
# #############################################################################
# LassoLarsIC: least angle regression with BIC/AIC criterion
model_bic = linear_model.LassoLarsIC(criterion='bic')
model_bic.fit(data, label)
# alpha_bic_ = model_bic.alpha_
model_aic = linear_model.LassoLarsIC(criterion='aic')
model_aic.fit(data, label)
# alpha_aic_ = model_aic.alpha_
plt.figure()
plot_ic_criterion(model_aic, 'AIC', 'b', EPSILON)
plot_ic_criterion(model_bic, 'BIC', 'r', EPSILON)
plt.legend()
plt.title('Information-criterion for model selection')
plt.savefig('information_criterion_model_selection.png')
# #############################################################################
# LassoCV: coordinate descent
# Compute paths
model = linear_model.LassoCV(cv=10).fit(data, label)
# Display results
m_log_alphas = -np.log10(model.alphas_ + EPSILON)
plt.figure()
ymin, ymax = 20, 300
plt.plot(m_log_alphas, model.mse_path_, ':')
plt.plot(m_log_alphas,
model.mse_path_.mean(axis=-1),
'k',
label='Average across the folds',
linewidth=2)
plt.axvline(-np.log10(model.alpha_ + EPSILON),
linestyle='--',
color='k',
label='alpha: CV estimate')
plt.legend()
plt.xlabel('-log(alpha)')
plt.ylabel('Mean square error')
plt.title('Mean square error on each fold: coordinate descent ')
plt.axis('tight')
plt.ylim(ymin, ymax)
plt.savefig('lasso_model_selection.png')
# #############################################################################
# LassoLarsCV: least angle regression
# Compute paths
model = linear_model.LassoLarsCV(cv=10).fit(data, label)
# Display results
m_log_alphas = -np.log10(model.cv_alphas_ + EPSILON)
plt.figure()
plt.plot(m_log_alphas, model.mse_path_, ':')
plt.plot(m_log_alphas,
model.mse_path_.mean(axis=-1),
'k',
label='Average across the folds',
linewidth=2)
plt.axvline(-np.log10(model.alpha_),
linestyle='--',
color='k',
label='alpha CV')
plt.legend()
plt.xlabel('-log(alpha)')
plt.ylabel('Mean square error')
plt.title('Mean square error on each fold: Lars')
plt.axis('tight')
plt.ylim(ymin, ymax)
plt.savefig('lasso_Lars_model_selection.png')
),
])
X, y = make_xy_data('./data/merged_data.csv', ['surface_m2', 'piece'])
X_train, X_test, y_train, y_test = train_test_split(X, y,
test_size=0.2,
random_state=2)
X_tr = features.fit_transform(X_train, None)
X_te = features.transform(X_test)
###############################################################################
t1 = time.time()
model = lm.LassoCV(cv=20, verbose=2).fit(X_tr, y_train)
t = time.time() - t1
# Display results
m_log_alphas = -np.log10(model.alphas_)
plt.figure()
plt.plot(m_log_alphas, model.mse_path_, ':')
plt.plot(m_log_alphas, model.mse_path_.mean(axis=-1), 'k',
label='Average across the folds', linewidth=2)
plt.axvline(-np.log10(model.alpha_), linestyle='--', color='k',
label='alpha: CV estimate')
plt.legend()
plt.xlabel('-log(alpha)')
plt.ylabel('Mean square error')
plt.title('Mean square error on each fold: coordinate descent'
' (train time: %.2fs)' % t)
# features is the cols - 1 (the 1 is the output label)
numFeatures = dataframe.shape[1] - 1
print(numFeatures)
X = dataframe[features].values
Y = dataframe[output_label]
# prepare configuration for cross validation test harness
num_folds = 10
seed = 7
# prepare models
models = []
models.append(('LR', LinearRegression()))
models.append(('Ridge', Ridge()))
#models.append(('ARDRegression', linear_model.ARDRegression()))
models.append(('Lasso', linear_model.Lasso()))
models.append(('LassoCV', linear_model.LassoCV()))
models.append(('LassoLars', linear_model.LassoLars()))
# Decision tree
models.append(('Dec tree', tree.DecisionTreeRegressor()))
# sanity check
models.append(('Dummy', DummyRegressor("median")))
def keras_baseline_model():
# create model
model = Sequential()
model.add(
Dense(128, input_dim=numFeatures, init='normal', activation='relu'))
model.add(Dense(1, init='normal', activation="relu"))
# Compile model
def _get_cv_model(self, alphas=None, kfold=None, l1_ratio=None, **kargs):
return linear_model.LassoCV(alphas=alphas, cv=kfold, **kargs)
# load data
#path=#pwd#'path to the file/'
df=pd.read_csv('ex1data2.txt',header=None)
df.columns=['Size','Bedrooms','Price'] # rename columns
## Inputs (X) and labels (y) (Population and profit in restaurent business)
y=np.array(df['Price'])
X=np.array(df.drop(['Price'],1))
X=X.astype('float64')
Sscaler=preprocessing.StandardScaler()
Xs=Sscaler.fit_transform(X)
# Robust scaler is very helpful in handling outliers
#Rscaler=preprocessing.RobustScaler()
#Xr=Rscaler.fit_transform(X)
# linear regression model
Lreg=linear_model.LassoCV(eps=0.08,max_iter=400,tol=1e-5)
#
Lreg.fit(Xs,y)
#
#print('------ Multivariate Linear Regression------------')
print('Accuracy of Linear Regression Model is ',round(Lreg.score(Xs,y)*100,2))
#
# predicting price of house with 1650 sq. feet in size with 3 bed rooms
Predict1=Lreg.predict(Sscaler.transform(np.reshape([1650,3],(1,-1))))
print('Predicted price of a house with 1650 sq. feet and 3 bed room is $', round(Predict1[0],2))
def __fit(self):
X_train, X_test, y_train, y_test = train_test_split(self.data, self.target, test_size=0.33, random_state=42)
self.lr = linear_model.LassoCV()
self.lr.fit(X_train, y_train)
fig1 = plt.figure(figsize=(12, 8))
ax1 = fig1.add_subplot(111)
ax1.set_xscale('log')
ax1.plot(penalisations, coeffs)
plt.xlabel("Penalisations")
plt.ylabel("thetas")
# Question 5
# Determinitation of the penalisation factor with Cross Validation
#lasscv = linear_model.LassoCV(cv=20)
lassCV = linear_model.LassoCV(alphas=penalisations,
fit_intercept=False,
normalize=False)
lassCV.fit(X, y)
# Question 5b
print "Lasso with CV : "
print "Penalisation trouvée par CV : " + str(lassCV.alpha_)
# Determining the smallest penalisation factor so that all coefficients equal to 0.
# Question 5c
x_test = np.array([6, 0.3, 0.2, 6, 0.053, 25, 149, 0.9934, 3.24, 0.35, 10])
print "Score : "
print lassCV.predict(x_test)
lr.score(XDF.values, y)
from sklearn import linear_model as lm
r = lm.Ridge().fit(XDF.values, y)
get_ipython().run_line_magic('pinfo', 'r.score')
r.score(XDF.values, y)
r = lm.Ridge(alpha=0.5).fit(XDF.values, y)
r.score(XDF.values, y)
get_ipython().run_line_magic('pinfo', 'lm.RidgeCV')
get_ipython().run_line_magic('pinfo', 'lm.RidgeCV')
rcv = lm.RidgeCV(alphas=[0.001, 0.01, 0.1, 1, 10, 100, 1000], cv=5)
rcv.fit(XDF.values, y)
rcv
rcv.score(XDF.values, y)
get_ipython().set_next_input('lasso = lm.LassoCV')
get_ipython().run_line_magic('pinfo', 'lm.LassoCV')
lasso = lm.LassoCV(n_jobs=-1, cv=5)
lasso.fit(XDF.values, y)
lasso.score(XDF.values, y)
lasso.coef_
rcv.coef_
ecv = lm.ElasticNetCV()
ecv.fit(XDF.values, y)
ecv.score(XDF.values, y)
from sklearn.feature_selection import RFECV
RFECV.head()
RFECV
lr = lm.LinearRegression()
rfecv = RFECV()
rfecv = RFECV(lr, cv=5, n_jobs=-1)
rfecv.fit(XDF.values, y)
rfecv.grid_scores_
df = pd.read_csv("input_data.csv") # pandasでcsvを読込
df = pd.DataFrame(df) # DataFrame形式にする
df = df.loc[df["play_time"] >= df["play_time"].median()] # プレイタイム上位半分のデータを選択
data_y = df["probability_6man"] # DataFrameから，yとして使用する列を抽出
drop_idx = ["player_id", "frag_starting", "play_time", "frag_6man",
"period", "position", "probability_6man"] # xとして使用しない列を選択
data_x = df.drop(drop_idx, axis=1) # DataFrameから，xとして使用する列を抽出
data_y = np.array(data_y, dtype=float) # numpyのarray形式にすることで演算可能になる
data_x = np.array(data_x, dtype=float)
data_x = (data_x - data_x.mean(axis=0)) / data_x.std(axis=0) # xを標準化
# ハイパーパラメータを交差確認法により推定
# sklearnのlinear_modelにあるLassoCV（Lassoの交差確認法のひとつ。LassoCVの他にもう一つやり方があったんだけど関数名が出てこない……）を、lasso_cvと定義
lasso_cv = linear_model.LassoCV()
lasso_cv.fit(data_x, data_y) # data_xとdata_yをlasso_cvにかける
# alphaとして交差確認法で算出した値を使用
# lasso = linear_model.Lasso(alpha=lasso_cv.alpha_)
lasso = linear_model.Lasso(alpha=0)
lasso.fit(data_x, data_y)
c = np.array(lasso.coef_) # cは係数のベクトル
# 結果の表示
print("交差確認法により推定された適切なハイパーパラメータ alpha :")
print(lasso_cv.alpha_) # 交差確認法の結果を表示，ハイパーパラメータalphaを返す
print() # 1行空ける
print("LASSO により推定されたパラメータ:")
print(c)
print() # 1行空ける
# -------------------------------------------------
# <editor-fold desc="COMMON VARIABLES">
smoothing_time = 0.2 # The smoothing window for both the firing rates and the distance to poke time series
smoothing_frames = int(smoothing_time / 0.00833)
fr_final_smoothing_time = 1 # The final smoothing window of the firing rates
fr_extra_smoothing_frames = int(fr_final_smoothing_time / smoothing_time)
leave_percentage_out = 0.005
model = pipeline.make_pipeline(PolynomialFeatures(2),
linear_model.LinearRegression())
model_npb_dtp = pipeline.make_pipeline(
PolynomialFeatures(2), linear_model.LassoCV(cv=None, fit_intercept=True))
common_pb_npb_dtp_neuron_indices = np.intersect1d(
correlated_neuron_indices['pb_dtp'], correlated_neuron_indices['npb_dtp'])
correlated_neuron_indices_unique_pb_dtp = np.delete(
correlated_neuron_indices['pb_dtp'],
np.argwhere(
np.isin(correlated_neuron_indices['pb_dtp'],
common_pb_npb_dtp_neuron_indices)))
correlated_neuron_indices_unique_npb_dtp = np.delete(
correlated_neuron_indices['npb_dtp'],
np.argwhere(
np.isin(correlated_neuron_indices['npb_dtp'],
common_pb_npb_dtp_neuron_indices)))
这里不给出原始公式推导，因为相比较岭回归，LASSO回归的区别不大
二者之间主要是正则化项不相同
在代价函数方面：
岭回归：1/(2*m)[sum(i=1->m)(hθ(xi)-yi)^2]+λ*sum(j=0->n)θj^2
LASSO回归:1/(2*m)[sum(i=1->m)(hθ(xi)-yi)^2]+λ*sum(j=0->n)|θj|
LASSO回归具有更强的解释性，他将与其他特征线性相关的特征系数置于0
详细数学细节不予赘述
"""
import numpy as np
from sklearn import linear_model
# 读入数据
data = np.genfromtxt("longley.csv", delimiter=",")
x_data = data[1:, 2:]
y_data = data[1:, 1]
# 训练LASSO
model = linear_model.LassoCV()
model.fit(x_data, y_data)
# lasso 系数
print("Lasso系数: ", model.alpha_)
# 相关系数
# 这里打印出的系数有0说明存在多重共线性
print("相关系数: ", model.coef_)
# 做一个预测
predict = model.predict(x_data[-2, np.newaxis])
print(predict)
X_test = np.array(X_test)
Y_test = []
for y in raw_test:
Y_test.append(y['Value'])
Y_test = np.array(Y_test, np.double)
# train
cvParams = [
0.000003, 0.00001, 0.00003, 0.0001, 0.0003, 0.001, 0.003, 0.01, 0.03, 0.1,
0.3
]
clf1 = linear_model.RidgeCV(alphas=cvParams,
normalize=True,
scoring='mean_squared_error')
clf1.fit(X, Y)
clf2 = linear_model.LassoCV(alphas=cvParams, normalize=True, max_iter=2000)
clf2.fit(X, Y)
clf3 = linear_model.ElasticNetCV(max_iter=2000, eps=0.0001)
clf3.fit(X, Y)
print 'Ridge:', clf1.coef_, clf1.intercept_, clf1.alpha_
print 'Lasso:', clf2.coef_, clf2.intercept_, clf2.alpha_, np.min(
clf2.mse_path_)
print 'ElasticNet:', clf3.coef_, clf3.intercept_, clf3.alpha_, np.min(
clf3.mse_path_)
# test
print 'Ridge:', np.mean((clf1.predict(X_test) - Y_test)**2)
print 'Lasso:', np.mean((clf2.predict(X_test) - Y_test)**2)
print 'ElasticNet:', np.mean((clf3.predict(X_test) - Y_test)**2)
# plot
