有人能帮助我使以下证明更专业吗:
Overleaf 模板:
\usepackage{amsmath}
\begin{equation*}
\begin{split}
sup_{z\in \mathrm{R}}|\hat{F}(z)-\widetilde {F}(z)| = sup_{z\in \mathrm{R}}\left|\frac{1}{n}
\sum_{t=1}^{n}\left\{\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-\hat{z}_{t}}{h}\right) d u
-\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-z_{t}}{h}\right) d u\right\}\right|\\
& = sup_{z\in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}\left\{\int_{-\infty}^{\frac{z-\hat{z}_{t}}
{h}} k(v) dv - \int_{-\infty}^{\frac{z-{z}_{t}}{h}} k(v) dv\right\}\right|, \text{By using
$v=\frac{u-\hat{z}_{t}}{h}$ and $dv=\frac{1}{h}du$} \\
& = sup_{z\in \mathrm{R}}\left|=\frac{1}{n} \sum_{t=1}^{n} \left\{G\left(\frac{z-\hat{z}_{t}}
{h}\right)-G\left(\frac{z-z_{t}}{h}\right)\right\}\right|, \text{By using $G(z)=\int_{-
\infty}^{z}k(v)dv$}\\
& = sup_{z\in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}\left\{G\left(\frac{z-z_{t}}
{h}\right)+G\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right) + \frac{1}{2 !}
G^{\prime \prime}\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}-
\at{z}_{t}}{h}\right)^{2} + \frac{1}{3 !} G^{\prime \prime \prime}\left(\frac{z-z_{t}}
{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)^{3} +R_{t} -G\left(\frac{z-z_{t}}
{h}\right)\right\}\right|, \text{By using third-order Taylor Expension centered about $\frac{z-z_{t}}
{h}$} \\
& = sup_{z\in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}\left\{G\left(\frac{z-z_{t}}
{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)+\frac{1}{2 !} G^{\prime \prime}\left(\frac{z-
z_{t}} {h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)^{2} + \frac{1}{3 !} G^{\prime \prime
\prime}\left(\frac{z-
z_{t}} {h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)^{3}+R_{t} \right\}\right| \\
& \quad \leq sup_{z\in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}G\left(\frac{z-z_{t}}
{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)\right| + sup_{z\in \mathrm{R}}\left|\frac{1}{n}
\sum_{t=1}^{n}\frac{1}{2 !} G^{\prime\prime}\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}-
\hat{z}_{t}}{h}\right)^{2} \right|\\
& \quad + sup_{z\in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} \frac{1}{3!} G^{\prime \prime
\prime}\left(\frac{z-z_{t}} {h}\right)\left(\frac{z_{t}- \hat{z}_{t}}{h}\right)^{3} \right| +
sup_{z\in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} R_{t}\right|\\
\end{split}
\end{equation*}
Let
\begin{equation*}
I_{1}=sup_{z\in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}G\left(\frac{z-
z_{t}}
{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)\right|
\end{equation*}
\begin{equation*}
I_{2}=sup_{z\in \mathrm{R}}\left|\frac{1}{n}
\sum_{t=1}^{n}\frac{1}{2 !} G^{\prime\prime}\left(\frac{z-z_{t}}
{h}\right)\left(\frac{z_{t}-
\hat{z}_{t}}{h}\right)^{2} \right|
\end{equation*}
\begin{equation*}
I_{3}=sup_{z\in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} \frac{1}{3!}
G^{\prime \prime
\prime}\left(\frac{z-z_{t}} {h}\right)\left(\frac{z_{t}- \hat{z}_{t}}
{h}\right)^{3} \right|
\end{equation*}
\begin{equation*}
I_{4}= sup_{z\in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} R_{t}\right|
\end{equation*}
答案1
我将在长篇展示之前解释替换并宣布泰勒展开的用途;读者将能够看到它们实际在哪里使用。
\documentclass{article}
\usepackage{amsmath,amssymb}
\newcommand{\numberset}[1]{\mathbb{#1}}% or whatever you prefer
\newcommand{\R}{\numberset{R}}
\newcommand{\diff}{\mathop{}\!d}
\begin{document}
We can use the substitutions
\begin{equation*}
G(z)=\int_{-\infty}^{z}k(v) \diff v,
\qquad
v=\frac{u-\hat{z}_{t}}{h},\quad \diff v=\frac{1}{h}\diff u
\end{equation*}
and, by using the third-order Taylor expansion centered about $(z-z_{t})/h$ of $G$,
compute
\begin{equation*}
\begin{split}
&\! \sup_{z\in \R}|\hat{F}(z)-\tilde {F}(z)|
\\
&=\sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n}\biggl\{
\int_{-\infty}^{z} \frac{1}{h} k\biggl(\frac{u-\hat{z}_{t}}{h}\biggr)\diff u
-\int_{-\infty}^{z} \frac{1}{h} k\biggl(\frac{u-z_{t}}{h}\biggr)\diff u
\biggr\}
\biggr|
\\
&=\sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n}\biggl\{
\int_{-\infty}^{\frac{z-\hat{z}_{t}}{h}} k(v)\diff v
- \int_{-\infty}^{\frac{z-{z}_{t}}{h}} k(v)\diff v
\biggr\}
\biggr|
\\
&=\sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n} \biggl\{
G\biggl(\frac{z-\hat{z}_{t}}{h}\biggr)
-G\biggl(\frac{z-z_{t}}{h}\biggr)
\biggr\}
\biggr|
\\
&=\sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n}\biggl\{
\begin{aligned}[t]
& G\biggl(\frac{z-z_{t}}{h}\biggr)+
G\biggl(\frac{z-z_{t}}{h}\biggr)\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)
+ \frac{1}{2!} G''\biggl(\frac{z-z_{t}}{h}\biggr)
\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)^{\!2}
\\
& + \frac{1}{3!} G'''\biggl(\frac{z-z_{t}}{h}\biggr)
\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)^{\!3}
+ R_{t} -G\biggl(\frac{z-z_{t}}{h}\biggr)
\biggr\}\biggr|\end{aligned}
\\
& = \sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n}\biggl\{
\begin{aligned}[t]
& G\biggl(\frac{z-z_{t}}{h}\biggr)\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)
+ \frac{1}{2!} G''\biggl(\frac{z-z_{t}} {h}\biggr)
\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)^{\!2}
\\
& + \frac{1}{3 !} G'''\biggl(\frac{z-z_{t}} {h}\biggr)
\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)^{\!3}
+R_{t}
\biggr\}\biggr|\end{aligned}
\\
&\leq \begin{aligned}[t]
&\! \sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n}G\biggl(\frac{z-z_{t}} {h}\biggr)
\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)
\biggr|
+ \sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n}\frac{1}{2!} G''\biggl(\frac{z-z_{t}}{h}\biggr)
\biggl(\frac{z_{t}-\hat{z}_{t}}{h}\biggr)^{\!2}
\biggr|
\\
& + \sup_{z\in \R}\biggl|
\frac{1}{n} \sum_{t=1}^{n} \frac{1}{3!} G'''\biggl(\frac{z-z_{t}} {h}\biggr)
\biggl(\frac{z_{t}- \hat{z}_{t}}{h}\biggr)^{\!3}
\biggr|
+ \sup_{z\in \R}\biggl| \frac{1}{n} \sum_{t=1}^{n} R_{t}\biggr|
\end{aligned}
\end{split}
\end{equation*}
\end{document}
这仍然会产生少量的溢出,但这取决于文档中设置的文本宽度。
需要注意的几点:我把所有的\left
and\right
都改成了\biggl
and \biggr
,这样可以更好地控制并减少间距。此外,大括号的指数前面要加上 ,\!
以避免它们无处可去。
答案2
这只是一个起点:您可以使用\intertext
带有公式的文本,并记住,如果公式被破坏,您应该使用\biggl(...\biggr)
,或\Biggl(...\Biggr)
(例如)等。我的建议是使用geometry
包来为整个页面提供更多空间。
\documentclass[a4paper,12pt]{article}
\usepackage{mathtools,amssymb}
\begin{document}
\[
\begin{split}
\sup_{z\in \mathbb{R}}|\hat{F}(z)-\widetilde {F}(z)|& = \sup_{z\in \mathbb{R}}\Biggl|\frac{1}{n}
\sum_{t=1}^{n}\left\{\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-\hat{z}_{t}}{h}\right) d u
-\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-z_{t}}{h}\right) d u\right\}\Biggr|\\
& = \sup_{z\in \mathbb{R}}\left|\frac{1}{n} \sum_{t=1}^{n}\left\{\int_{-\infty}^{\frac{z-\hat{z}_{t}}
{h}} k(v) dv - \int_{-\infty}^{\frac{z-{z}_{t}}{h}} k(v) dv\right\}\right|
\intertext{$v=\frac{u-\hat{z}_{t}}{h}$ and $dv=\frac{1}{h}du$}
\sum & = \sup_{z\in \mathbb{R}}\Biggl|\frac{1}{n}
\sum_{t=1}^{n}\left\{\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-\hat{z}_{t}}{h}\right) d u
-\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-z_{t}}{h}\right) d u\right\}\Biggr|\\
& = \sup_{z\in \mathbb{R}}\left|\frac{1}{n} \sum_{t=1}^{n}\left\{\int_{-\infty}^{\frac{z-\hat{z}_{t}}
{h}} k(v) dv - \int_{-\infty}^{\frac{z-{z}_{t}}{h}} k(v) dv\right\}\right|
\end{split}
\]
\end{document}
答案3
这是一种可能性,在环境中的相关位置使用multlined
& 。我还使用中等大小的分数 ( )作为数值分数系数:aligned
split
\mfrac
nccmath
\documentclass{article}
\usepackage{nccmath, mathtools}
\usepackage[showframe]{geometry}
\begin{document}
\begin{equation*}
\begin{split}
\MoveEqLeft[-1]\sup_{z\in \mathrm{R}}|\hat{F}(z)-\widetilde{F}(z)|
= \sup_{z\in \mathrm{R}}\left|\frac{1}{n}
\sum_{t=1}^{n}\left\{\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-\hat{z}_{t}}{h}\right) d u
-\int_{-\infty}^{z} \frac{1}{h} k\left(\frac{u-z_{t}}{h}\right) d u\right\}\right|\\
& = \sup_{z\in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}\left\{\int_{-\infty}^{\frac{z-\hat{z}_{t}}
{h}} k(v) dv - \int_{-\infty}^{\frac{z-{z}_{t}}{h}} k(v) dv\right\}\right|,\qquad
\text{by using $v=\frac{u-\hat{z}_{t}}{h}$ and $dv=\frac{1}{h}du$}\\
& = \sup_{z\in \mathrm{R}}\left|=\frac{1}{n} \sum_{t=1}^{n} \left\{G\left(\frac{z-\hat{z}_{t}}
{h}\right)-G\left(\frac{z-z_{t}}{h}\right)\right\}\right|, \qquad\enspace
\text{setting $G(z)=\int_{- \infty}^{z}k(v)dv$}\\
\intertext{and by using third-order Taylor Expansion centered about $\frac{z-z_{t}}{h}$\vskip 2ex}
& \begin{multlined}[t][0.95\linewidth]= \sup_{z\in \mathrm{R}}\biggl|\frac{1}{n} \sum_{t=1}^{n}\biggl\{G\left(\frac{z-z_{t}}
{h}\right) +G\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)+ \mfrac{1}{2!}
G''\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}- \hat{z}_{t}}{h}\right)^{2}\\[-1.5ex]
+ \mfrac{1}{3!} G'''\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)^{3} +R_{t} -G\left(\frac{z-z_{t}}
{h}\right)\biggr\}\biggr|,\end{multlined} %
\\
&\begin{multlined}[t][0.95\linewidth] = \sup_{z\in \mathrm{R}}\biggl|\frac{1}{n} \sum_{t=1}^{n}\biggl\{G\left(\frac{z-z_{t}}
{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)+\mfrac{1}{2 !} G''\left(\frac{z-
z_{t}} {h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)^{2}\\[-1.5ex]
-\mfrac{1}{3 !} G'''\left(\frac{z-z_{t}} {h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)^{3}+R_{t} \biggr\}\biggr| ,\end{multlined} %
\\
& \leq \begin{aligned}[t]\sup_{z\in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}G\left(\frac{z-z_{t}}
{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)\right| & + \sup_{z\in \mathrm{R}}\left|\frac{1}{n}
\sum_{t=1}^{n}\mfrac{1}{2 !} G''\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}-
\hat{z}_{t}}{h}\right)^{2} \right|\\
& + \sup_{z\in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} \mfrac{1}{3!} G''' \left(\frac{z-z_{t}} {h}\right)\left(\frac{z_{t}- \hat{z}_{t}}{h}\right)^{3} \right| +
\sup_{z\in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} R_{t}\right| \end{aligned}%
\end{split}
\end{equation*}
\end{document}
至于第二部分,我将以稍有不同的方式排列,分为两行:
Let%
\begin{align*}
I_{1} & =\sup_{z \in \mathrm{R}}\left|\frac{1}{n} \sum_{t=1}^{n}G\left(\frac{z-z_{t}}{h}\right)\left(\frac{z_{t}-\hat{z}_{t}}{h}\right)\right|, &
I_{2} & =\sup_{z \in \mathrm{R}}\left|\frac{1}{n}
\sum_{t=1}^{n}\mfrac{1}{2 !} G^{\prime\prime}\left(\frac{z-z_{t}} {h}\right)\left(\frac{z_{t}- \hat{z}_{t}}{h}\right)^{\!2} \right|, \\[1ex]
I_{3} & =\sup_{z \in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} \mfrac{1}{3!}G'''\left(\frac{z-z_{t}} {h}\right)\left(\frac{z_{t}- \hat{z}_{t}}{h}\right)^{\!3} \right| ,&
I_{4} & = \sup_{z \in \mathrm{R}}\left| \frac{1}{n} \sum_{t=1}^{n} R_{t}\right|.
\end{align*}