一.linear_model
3.线性回归器
(3)贝叶斯回归(Bayesian regressors):
"贝叶斯自动相关确定回归"(Bayesian Automatic Relevance Determination regression;Bayesian ARD regression):class sklearn.linear_model.ARDRegression([n_iter=300,tol=0.001,alpha_1=1e-06,alpha_2=1e-06,lambda_1=1e-06,lambda_2=1e-06,compute_score=False,threshold_lambda=10000.0,fit_intercept=True,normalize=False,copy_X=True,verbose=False])
#参数说明:
n_iter:指定最大迭代次数;为int
tol:指定最小误差(若误差小于该值,则停止);为float
alpha_1:指定alpha的Gamma分布先验概率的"形状参数"(shape parameter);为float
#shape parameter for the Gamma distribution prior over the alpha parameter
alpha_2:指定alpha的Gamma分布先验概率的"反比例/逆尺度参数"(inverse scale parameter)/"速率参数"(rate parameter);为float
#inverse scale parameter (rate parameter) for the Gamma distribution prior over the alpha parameter
lambda_1:指定lambda的Gamma分布先验概率的形状参数;为float
#shape parameter for the Gamma distribution prior over the lambda parameter
lambda_2:指定lambda的Gamma分布先验概率的逆尺参数;为float
#inverse scale parameter (rate parameter) for the Gamma distribution prior over the lambda parameter
#以上4个均为"超参数"(Hyper parameter)
compute_score:指定是否计算模型每1步的目标函数;为bool
threshold_lambda:指定从计算中以高精度删除(修剪)权重的阈值;为float
#threshold for removing (pruning) weights with high precision from the computation
fit_intercept:指定是否估计截距;为bool
normalize:指定是否先对数据进行归一化;为bool
#若为True,将进行如下变换:(X-mean)/l2-norm
#当fit_intercept=false时忽略该参数
copy_X:指定是否复制数据;为bool
verbose:指定输出信息的冗余度;为int/bool
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"贝叶斯岭回归"(Bayesian ridge regression):class sklearn.linear_model.BayesianRidge([n_iter=300,tol=0.001,alpha_1=1e-06,alpha_2=1e-06,lambda_1=1e-06,lambda_2=1e-06,alpha_init=None,lambda_init=None,compute_score=False,fit_intercept=True,normalize=False,copy_X=True,verbose=False])
#参数说明:其他参数同class sklearn.linear_model.ARDRegression()
alpha_init:指定alpha(噪声精度)的初始值;为float
lambda_init:指定lambda(权重精度)的初始值;为float
(4)带有变量选择的多任务线性回归器(Multi-task linear regressors with variable selection):
以"L1/L2混合范数"(L1/L2 mixed-norm)作为正则化器的"多任务弹性网络模型"(Multi-task ElasticNet model):class sklearn.linear_model.MultiTaskElasticNet([alpha=1.0,l1_ratio=0.5,fit_intercept=True,normalize=False,copy_X=True,max_iter=1000,tol=0.0001,warm_start=False,random_state=None,selection='cyclic'])
#参数说明:其他参数同class sklearn.linear_model.ARDRegression()
alpha:指定L1/L2惩罚项的系数;为float
l1_ratio:指定"正则化混合参数"(regularization mixing parameter);为0<=float<=1
#For l1_ratio=1 the penalty is an L1/L2 penalty
#For l1_ratio=0 it is an L2 penalty
#For 0<l1_ratio<1,the penalty is a combination of L1/L2 and L2
max_iter:指定最大迭代次数;为int
warm_start:指定是否启用"热重启"(warm start);为bool
random_state:指定用于初始化中心的随机数;为int/RandomState instance/None
selection:If set to "random",a random coefficient is updated every iteration
If set to "cyclic",features are looped over sequentially
#设为"random"通常会使收敛更快,尤其是当tol>1e-4时
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以L1/L2混合范数作为正则化器的带有交叉验证的多任务弹性网络模型:class sklearn.linear_model.MultiTaskElasticNetCV([l1_ratio=0.5,eps=0.001,n_alphas=100,