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\mathbb{E}_{\varepsilon}\big{[}g^{2}_{\tau}(\varepsilon)\big{]}=\mathbb{V}% \mbox{ar}\,[\varepsilon]
\mathbf{\kappa}
\displaystyle\qquad+\lambda_{n}\sum^{q}_{j=1}\widehat{\omega}_{n,j}\frac{{% \mathrm{sgn}}(\beta^{0}_{j})u_{j}}{\sqrt{n}}+o_{\mathbb{P}}(1)
100\frac{1}{M}\sum^{M}_{l=1}\frac{\big{|}\widehat{\cal A}^{c}_{n,l}\cap{\cal A% }\big{|}}{|{\cal A}|},
\widetilde{\tau}
\mathbb{E}_{\varepsilon}\big{[}h_{\tau}(\varepsilon)\big{]}\mathbf{{u}}^{\top}% \mathbb{E}_{\mathbf{X}}[\mathbf{X}\mathbf{X}^{\top}]\mathbf{{u}}
\beta^{0}_{1}=5\log(n)
l_{0}=0
t\in[0,B]
\widehat{\textrm{$\mathbf{\beta}$}}_{n}-\textrm{$\mathbf{\beta}^{0}$}=O_{% \mathbb{P}}(n^{-1/2})
\displaystyle=\left\{Q_{n}(G_{0},\textrm{$\mathbf{\beta}^{0}$}+n^{-1/2}\mathbf% {{u}})-Q_{n}(G_{0},\textrm{$\mathbf{\beta}^{0}$})\right\}
\lambda_{n}n^{(\gamma-1)/2}{\underset{n\rightarrow\infty}{\longrightarrow}}\infty
{\cal S}^{c}
\mathbf{{u}}_{\cal A}=-\mathbb{E}^{-1}_{\varepsilon}[h_{\tau}(\varepsilon)]% \mathbb{E}_{\mathbf{X}}[\mathbf{X}_{{\cal A}}\mathbf{X}^{\top}_{{\cal A}}]^{-1% }\bigg{(}\textbf{W}_{3}+l_{0}\widehat{\textrm{$\mathbf{\omega}$}}_{n,{\cal A}}% {\mathrm{sgn}}(\textrm{$\mathbf{\beta}$}^{0}_{\cal A})\bigg{)}.
\rho_{\tau}(x)=|\tau-1\!\!1_{x<0}|x^{2},\qquad x\in\mathbb{R},
\widehat{\omega}_{n,j}=O_{\mathbb{P}}(1)
\widetilde{\textrm{$\mathbf{\beta}$}}_{n,{\cal A}}
\delta_{i}\equiv 1\!\!1_{T_{i}\leq{\cal C}_{i}}
X_{2i}\sim{\cal N}(1,5)
h_{\tau}(x)\equiv\rho^{\prime\prime}_{\tau}(x-t)|_{t=0}=2\tau 1\!\!1_{x\geq 0}% +2(1-\tau)1\!\!1_{x<0}
\widetilde{\textrm{$\mathbf{\beta}$}}_{n}-\textrm{$\mathbf{\beta}^{0}$}
{\cal T}_{n}(\widehat{G}_{n},\textrm{$\mathbf{\beta}$})={\cal R}_{n}(\widehat{% G}_{n},\textrm{$\mathbf{\beta}$})+\lambda_{n}\sum^{p}_{j=1}\widehat{\omega}_{n% ,j}\big{(}|\beta_{j}|-|\beta^{0}_{j}|\big{)},
\mathbb{P}[{\cal A}=\widehat{\cal A}_{n}]{\underset{n\rightarrow\infty}{% \longrightarrow}}1
j\in\{6,\cdots,p\}
\lambda_{n}=n^{1/2-0.01}
k\in\{2,3\cdots,10\}
\mathbb{P}_{\cal C}
\displaystyle+\sum^{n}_{i=1}\delta_{i}\bigg{(}\frac{1}{\widehat{G}_{n}(Y_{i})}% -\frac{1}{G_{0}(Y_{i})}\bigg{)}\bigg{\{}\bigg{(}g_{\tau}(\varepsilon_{i})% \mathbf{X}^{\top}_{i}\big{(}\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}}-\textrm% {$\mathbf{\beta}^{0}$}_{\cal A},\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}^{c}}% \big{)}+\frac{h_{\tau}(\varepsilon_{i})}{2}\big{(}\mathbf{X}^{\top}_{i}\big{(}% \textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}}-\textrm{$\mathbf{\beta}^{0}$}_{\cal A% },\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}^{c}}\big{)}\big{)}^{2}
s,t\in[0,B]
p\in\{50,150\}
\beta_{0}^{0}=2
Q_{n}(\widehat{G}_{n},\textrm{$\mathbf{\beta}$}^{(2)})-Q_{n}(\widehat{G}_{n},% \textrm{$\mathbf{\beta}$}^{(1)})=O_{\mathbb{P}}(1).
\beta^{0}_{0},\beta^{0}_{1},\cdots,\beta^{0}_{p}
\mathbb{E}_{\varepsilon}[g_{\tau}(\varepsilon)]=\mathbb{E}_{\varepsilon}[% \varepsilon]=0
(X_{1},\cdots,X_{p})
t=\mathbf{X}^{\top}_{i}(\textrm{$\mathbf{\beta}$}^{(1)}-\textrm{$\mathbf{\beta% }^{0}$})
\displaystyle\qquad+\frac{1}{n}\sum^{n}_{i=1}\frac{\delta_{i}}{G_{0}(Y_{i})}g_% {\tau}(\varepsilon_{i})\frac{\mathbf{X}^{\top}_{{\cal A},i}\mathbf{{u}}_{\cal A% }}{\sqrt{n}}\sum^{n}_{j=1}\int^{B}_{0}\frac{1\!\!1_{Y_{i}\geq s}}{y(s)}dM^{% \cal C}_{j}(s)\bigg{\}}\big{(}1+o_{\mathbb{P}}(1)\big{)}+\lambda_{n}\sum^{q}_{% j=1}\widehat{\omega}_{n,j}\frac{{\mathrm{sgn}}(\beta^{0}_{j})u_{j}}{\sqrt{n}},
\displaystyle=\frac{\mathbb{E}_{\varepsilon}[h_{\tau}(\varepsilon)]}{2}\mathbf% {{u}}^{\top}_{\cal A}\mathbb{E}_{\mathbf{X}}[\mathbf{X}_{{\cal A}}\mathbf{X}^{% \top}_{{\cal A}}]\mathbf{{u}}_{\cal A}+\frac{\mathbf{{u}}^{\top}_{\cal A}}{% \sqrt{n}}\sum^{n}_{i=1}\bigg{(}\frac{\delta_{i}}{G_{0}(Y_{i})}g_{\tau}(% \varepsilon_{i})\mathbf{X}_{{\cal A},i}+\int^{B}_{0}\frac{\textrm{$\mathbf{% \kappa}$}_{\cal A}(s)}{y(s)}dM^{\cal C}_{i}(s)\bigg{)}
{\cal N}_{p}(\textbf{m},\textbf{V})
\displaystyle-\bigg{(}g_{\tau}(\varepsilon_{i})\mathbf{X}^{\top}_{{\cal A},i}% \big{(}\textrm{$\mathbf{\beta}$}^{(2)}-\textrm{$\mathbf{\beta}^{0}$}\big{)}_{% \cal A}+\frac{h_{\tau}(\varepsilon_{i})}{2}\big{(}\mathbf{X}^{\top}_{i,{\cal A% }}\big{(}\textrm{$\mathbf{\beta}$}^{(2)}-\textrm{$\mathbf{\beta}^{0}$}\big{)}_% {\cal A}\big{)}^{2}+o_{\mathbb{P}}\big{(}\mathbf{X}^{\top}_{{\cal A},i}\big{(}% \textrm{$\mathbf{\beta}$}^{(2)}-\textrm{$\mathbf{\beta}^{0}$}\big{)}_{\cal A}% \big{)}^{2}\bigg{)}\bigg{\}}
n^{1/2}(\widetilde{\textrm{$\mathbf{\beta}$}}_{n}-\textrm{$\mathbf{\beta}^{0}$% })\overset{\cal L}{\underset{n\rightarrow\infty}{\longrightarrow}}{\cal N}_{p}% (\textrm{$\mathbf{0}$}_{p},\textbf{S}^{-1}_{3}(\textbf{S}_{1}+\textbf{S}_{2})% \textbf{S}^{-1}_{3})
\sqrt{n}\big{(}\widehat{\textrm{$\mathbf{\beta}$}}_{n,{\cal A}}-\textrm{$% \mathbf{\beta}$}^{0}_{\cal A}\big{)}\overset{\cal L}{\underset{n\rightarrow% \infty}{\longrightarrow}}{\cal N}_{|{\cal A}|}\bigg{(}-\mathbb{E}^{-1}_{% \varepsilon}[h_{\tau}(\varepsilon)]l_{0}{\textrm{$\mathbf{\omega}$}^{0}_{\cal A% }}^{\top}{\mathrm{sgn}}(\textrm{$\mathbf{\beta}$}^{0}_{\cal A})\mathbb{E}_{% \mathbf{X}}[\mathbf{X}_{{\cal A}}\mathbf{X}^{\top}_{{\cal A}}]^{-1},\textrm{$% \mathbf{\Xi}$}\bigg{)},
\mathbb{E}_{\varepsilon}[\varepsilon^{4}]<\infty
n<1500
l_{0}>0
\widehat{\cal A}_{n,l}
c=\|\mathbf{{u}}\|
\frac{1}{n}\sum^{n}_{i=1}\frac{\delta_{i}}{G_{0}(Y_{i})}\frac{h_{\tau}(% \varepsilon_{i})}{2}\big{(}\mathbf{X}^{\top}_{i}\big{(}\textrm{$\mathbf{\beta}% $}^{(2)}_{{\cal A}}-\textrm{$\mathbf{\beta}^{0}$}_{\cal A},\textrm{$\mathbf{% \beta}$}^{(2)}_{{\cal A}^{c}}\big{)}\big{)}^{2}=O_{\mathbb{P}}\big{(}\|\textrm% {$\mathbf{\beta}$}^{(2)}-\textrm{$\mathbf{\beta}^{0}$}\|^{2}\big{)}=O_{\mathbb% {P}}(n^{-1}).
\lambda_{n}=n^{1/2}
{\cal R}_{n}(\widehat{G}_{n},\textrm{$\mathbf{\beta}$})\equiv\sum^{n}_{i=1}% \frac{\delta_{i}}{\widehat{G}_{n}(Y_{i})}\bigg{(}\rho_{\tau}\big{(}\log(Y_{i})% -\mathbf{X}^{\top}_{i}\textrm{$\mathbf{\beta}$}\big{)}-\rho_{\tau}(\varepsilon% _{i})\bigg{)}=\sum^{n}_{i=1}\frac{\delta_{i}}{\widehat{G}_{n}(Y_{i})}\bigg{(}% \rho_{\tau}\big{(}\varepsilon_{i}-n^{-1/2}\mathbf{X}^{\top}_{i}\mathbf{{u}}% \big{)}-\rho_{\tau}(\varepsilon_{i})\bigg{)}.
\big{(}\widehat{\beta}_{n,1},\cdots,\widehat{\beta}_{n,p}\big{)}
\textbf{v}_{3}\equiv\frac{\delta}{G_{0}(Y)}g_{\tau}(\varepsilon)\mathbf{X}_{{% \cal A}}+\int^{B}_{0}\frac{\textrm{$\mathbf{\kappa}$}_{\cal A}(s)}{y(s)}dM^{% \cal C}(s)
X_{1i}\sim{\cal N}(1,1)
l_{0}\neq 0
\mathbb{E}_{\mathbf{X}}
\beta^{0}_{5}=-1
\widetilde{\textrm{$\mathbf{\beta}$}}_{n}\equiv\mathop{\mathrm{arg\,min}}_{% \textrm{$\mathbf{\beta}$}\in\mathbb{R}^{p}}\sum^{n}_{i=1}\frac{\delta_{i}}{% \widehat{G}_{n}(Y_{i})}\rho_{\tau}(\log(Y_{i})-\mathbf{X}_{i}^{\top}\textrm{$% \mathbf{\beta}$}),
L2\equiv\|\widetilde{\textrm{$\mathbf{\beta}$}}_{n}-\textrm{$\mathbf{\beta}^{0% }$}\|
{\cal A}^{c}=\{q+1,\cdots,p\}
1-G_{0}(t)
{\cal A}=\{1\}
{\cal V}(\textrm{$\mathbf{\beta}^{0}$})
{\cal T}_{n}(\widehat{G}_{n},\textrm{$\mathbf{\beta}^{0}$}+n^{-1/2}\mathbf{{u}})
\beta^{0}_{0}\neq 0
\displaystyle=\mathbb{E}_{\varepsilon}\big{[}g^{2}_{\tau}(\varepsilon_{i})\big% {]}\frac{\mathbf{{u}}^{\top}}{n}\mathbb{E}_{\mathbf{X}}\bigg{[}\frac{\mathbf{X% }\mathbf{X}^{\top}}{G_{0}(Y)}\bigg{]}\mathbf{{u}},
\textbf{S}_{1}\equiv\mathbb{E}_{\varepsilon}\big{[}g^{2}_{\tau}(\varepsilon)% \big{]}\mathbb{E}_{\mathbf{X}}\big{[}\mathbf{X}\mathbf{X}^{\top}/G_{0}(Y)\big{]}
n<2000
\displaystyle=\sum^{n}_{i=1}\frac{\delta_{i}}{G_{0}(Y_{i})}\bigg{\{}\bigg{(}g_% {\tau}(\varepsilon_{i})\mathbf{X}^{\top}_{i}\big{(}\textrm{$\mathbf{\beta}$}^{% (2)}_{{\cal A}}-\textrm{$\mathbf{\beta}^{0}$}_{\cal A},\textrm{$\mathbf{\beta}% $}^{(2)}_{{\cal A}^{c}}\big{)}+\frac{h_{\tau}(\varepsilon_{i})}{2}\big{(}% \mathbf{X}^{\top}_{i}\big{(}\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}}-\textrm% {$\mathbf{\beta}^{0}$}_{\cal A},\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}^{c}}% \big{)}\big{)}^{2}
g_{\tau}(x)\equiv\rho^{\prime}_{\tau}(x-t)|_{t=0}=-2\tau x1\!\!1_{x\geq 0}-2(1% -\tau)x1\!\!1_{x<0}
\beta^{0}_{0}
\textrm{$\mathbf{\Xi}$}=\textbf{S}^{-1}_{3,{\cal A}}(\textbf{S}_{1,{\cal A}}+% \textbf{S}_{2,{\cal A}})\textbf{S}^{-1}_{3,{\cal A}})
\|\textrm{$\mathbf{\beta}^{0}$}\|
\textbf{S}_{2}\equiv\mathbb{E}\big{[}\int^{B}_{0}{\textrm{$\mathbf{\kappa}$}(s% )\textrm{$\mathbf{\kappa}$}^{\top}(s)}/{y(s)}d\Lambda_{C}(s)\big{]}
(\widehat{\textrm{$\mathbf{\beta}$}}_{n}-\textrm{$\mathbf{\beta}^{0}$})_{\cal A}
\mathbb{P}_{\mathbf{X}}[\|\mathbf{X}\|<c]=1
\displaystyle Q_{n}(\widehat{G}_{n},\textrm{$\mathbf{\beta}$}^{(2)})-Q_{n}(% \widehat{G}_{n},\textrm{$\mathbf{\beta}$}^{(1)})=\sum^{n}_{i=1}\frac{\delta_{i% }}{\widehat{G}_{n}(Y_{i})}\bigg{(}\rho_{\tau}\big{(}\log(Y_{i})-\mathbf{X}_{i}% ^{\top}\textrm{$\mathbf{\beta}$}^{(2)}\big{)}-\rho_{\tau}\big{(}\log(Y_{i})-% \mathbf{X}_{i}^{\top}\textrm{$\mathbf{\beta}$}^{(1)}\big{)}\bigg{)}
\begin{split}\lambda_{n}\sum^{p}_{j=1}\widehat{\omega}_{n,j}\big{(}|\beta^{(2)% }_{j}|-|\beta^{(1)}_{j}|\big{)}&=\lambda_{n}\sum^{p}_{j=q+1}\widehat{\omega}_{% n,j}|\beta^{(2)}_{j}|\\ &\geq O_{\mathbb{P}}\big{(}\lambda_{n}n^{\gamma/2}n^{-1/2}\big{)}=O_{\mathbb{P% }}(\lambda_{n}n^{(\gamma-1)/2}){\underset{n\rightarrow\infty}{\longrightarrow}% }\infty.\end{split}
\rho_{\tau}(e-t)=\rho_{\tau}(e)+g_{\tau}(e)t+h_{\tau}(e)t^{2}/2+o(t^{2}).
n=150k
\textbf{W}_{1}+\mathbb{E}_{\varepsilon}\big{[}h_{\tau}(\varepsilon)\big{]}% \mathbb{E}_{\mathbf{X}}[\mathbf{X}\mathbf{X}^{\top}]\mathbf{{u}}+\textbf{W}_{2% }=\textrm{$\mathbf{0}$}_{p}.
(Y_{i},\mathbf{X}_{i},\delta_{i})_{1\leqslant i\leqslant n}
\displaystyle=\frac{\mathbb{E}_{\varepsilon}[h_{\tau}(\varepsilon)]}{2}\mathbf% {{u}}^{\top}_{\cal A}\mathbb{E}_{\mathbf{X}}[\mathbf{X}_{{\cal A}}\mathbf{X}^{% \top}_{{\cal A}}]\mathbf{{u}}_{\cal A}+\mathbf{{u}}^{\top}_{\cal A}\textbf{W}_% {3}+l_{0}\widehat{\textrm{$\mathbf{\omega}$}}_{n,{\cal A}}{\mathrm{sgn}}(% \textrm{$\mathbf{\beta}$}^{0}_{\cal A})^{\top}\mathbf{{u}}_{\cal A},
S_{21}=O_{\mathbb{P}}(1)
V_{n}=O_{\mathbb{P}}(U_{n})
c>0\,\text{so that}\,\underset{n\rightarrow\infty}{\text{lim}}\mathbb{P}(|{U_{% n}}/{V_{n}}|>c)<e
\textrm{$\mathbf{\beta}^{0}$}=(\beta^{0}_{1},\cdots,\beta^{0}_{p})
\displaystyle=\sum^{n}_{i=1}\frac{\delta_{i}}{G_{0}(Y_{i})}\bigg{\{}\bigg{(}g_% {\tau}(\varepsilon_{i})\mathbf{X}^{\top}_{{\cal A}^{c},i}\textrm{$\mathbf{% \beta}$}^{(2)}_{{\cal A}^{c}}+\frac{h_{\tau}(\varepsilon_{i})}{2}\big{(}% \mathbf{X}^{\top}_{i}\big{(}\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}}-\textrm% {$\mathbf{\beta}^{0}$}_{\cal A},\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}^{c}}% \big{)}\big{)}^{2}+o_{\mathbb{P}}\big{(}\mathbf{X}^{\top}_{i}\big{(}\textrm{$% \mathbf{\beta}$}^{(2)}_{{\cal A}}-\textrm{$\mathbf{\beta}^{0}$}_{\cal A},% \textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}^{c}}\big{)}\big{)}\bigg{)}
\textrm{$\mathbf{\beta}^{0}$}=\big{(}\textrm{$\mathbf{\beta}$}^{0}_{\cal A},% \textrm{$\mathbf{0}$}_{|{\cal A}^{c}|}\big{)}
S_{22}
\frac{1}{n}\sum^{n}_{i=1}\frac{\delta_{i}}{G_{0}(Y_{i})}h_{\tau}(\varepsilon_{% i})\mathbf{{u}}^{\top}\mathbf{X}_{i}\mathbf{X}^{\top}_{i}\mathbf{{u}}\overset{% \mathbb{P}}{\underset{n\rightarrow\infty}{\longrightarrow}}\mathbb{E}\big{[}h_% {\tau}(\varepsilon)\mathbf{{u}}^{\top}\mathbf{X}\mathbf{X}^{\top}\mathbf{{u}}% \big{]}=\mathbb{E}_{\varepsilon}\big{[}h_{\tau}(\varepsilon)\big{]}\mathbf{{u}% }^{\top}\mathbb{E}_{\mathbf{X}}\big{[}\mathbf{X}\mathbf{X}^{\top}\big{]}% \mathbf{{u}}.
\displaystyle\qquad\qquad+o_{\mathbb{P}}\big{(}\mathbf{X}^{\top}_{i}\big{(}% \textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}}-\textrm{$\mathbf{\beta}^{0}$}_{\cal A% },\textrm{$\mathbf{\beta}$}^{(2)}_{{\cal A}^{c}}\big{)}\big{)}^{2}\bigg{)}
SD\equiv sd((\widehat{\textrm{$\mathbf{\beta}$}}_{n}-\textrm{$\mathbf{\beta}^{% 0}$})_{\cal A})
T^{*}_{i}=\beta^{0}_{0}+\sum^{p}_{j=1}\beta^{0}_{j}X_{ji}+\varepsilon_{i},% \qquad i=1,\cdots,n,
\lambda_{n}=n^{1/2-0.1}
\frac{1}{\sqrt{n}}\sum^{n}_{j=1}\int^{B}_{0}\frac{\textrm{$\mathbf{\kappa}$}_{% {\cal A}^{c}}(s)}{y(s)}dM^{\cal C}_{j}(s)\overset{\cal L}{\underset{n% \rightarrow\infty}{\longrightarrow}}\textbf{W}_{2,{\cal A}^{c}}\sim{\cal N}_{|% {\cal A}^{c}|}\big{(}\textrm{$\mathbf{0}$}_{|{\cal A}^{c}|},...\big{)},
T_{i}=\exp(T_{i}^{*})
\widehat{\omega}_{n,j}\equiv|\widetilde{\beta}_{n,j}|^{-\gamma}
\textbf{S}_{1,{\cal A}}
\textbf{W}_{1}+\textbf{W}_{2}\sim{\cal N}_{p}(\textrm{$\mathbf{0}$}_{p},% \textbf{S}_{1}+\textbf{S}_{2})
\mathbb{E}_{\varepsilon}[h_{0.5}(\varepsilon)]=1