统计代写|应用线性模型代写Applied Linear Models代考|STAT713

statistics-lab™ 为您的留学生涯保驾护航 在代写应用线性模型Applied Linear Models方面已经树立了自己的口碑, 保证靠谱, 高质且原创的统计Statistics代写服务。我们的专家在代写应用线性模型Applied Linear Models代写方面经验极为丰富，各种代写应用线性模型Applied Linear Models相关的作业也就用不着说。

• Statistical Inference 统计推断
• Statistical Computing 统计计算
• (Generalized) Linear Models 广义线性模型
• Statistical Machine Learning 统计机器学习
• Longitudinal Data Analysis 纵向数据分析
• Foundations of Data Science 数据科学基础

统计代写|应用线性模型代写Applied Linear Models代考|ARBITRARINESS IN A GENERALIZED INVERSE

The existence of many generalized inverse matrices $\mathbf{G}$ that satisfy $\mathbf{A G A}=$ $\mathbf{A}$ has been emphasized. We here examine the nature of the arbitrariness in such generalized inverses, as discussed by Urquhart (1969a). Some lemmas concerning rank are given first.

Lemma 7. A matrix of full row rank $r$ can be written as a product of matrices, one being of the form $\left[\begin{array}{ll}\mathbf{I}_r & \mathbf{S}\end{array}\right]$ for some matrix $\mathbf{S}$, of $r$ rows.

Proof. Suppose $\mathbf{B}_{r \times a}$ has full row rank $r$ and contains an $r \times r$ nonsingular minor, $\mathbf{M}$ say. Then, for some matrix $\mathbf{L}$ and some permutation

$\mathbf{B}=\mathbf{M}\left[\begin{array}{lll}I & M^{-1} \mathbf{L}\end{array}\right] \mathbf{Q}^{-1}=\mathbf{M}\left[\begin{array}{ll}\mathbf{I} & \mathbf{S}\end{array}\right] \mathbf{Q}^{-1}$, for $\quad \mathbf{S}=\mathbf{M}^{-1} \mathbf{L}$.
Lemma 8. $\mathbf{I}+\mathbf{K K}^{\prime}$ has full rank for any non-null matrix $\mathbf{K}$.
Proof. Assume that $\mathbf{I}+\mathbf{K K} \mathbf{K}^{\prime}$ does not have full rank. Then its columns are not LIN and there exists a non-null vector $\mathbf{u}$ such that
$$\left(\mathbf{I}+\mathbf{K} \mathbf{K}^{\prime}\right) \mathbf{u}=\mathbf{0}, \quad \text { so that } \quad \mathbf{u}^{\prime}\left(\mathbf{I}+\mathbf{K K}^{\prime}\right) \mathbf{u}=\mathbf{u}^{\prime} \mathbf{u}+\mathbf{u}^{\prime} \mathbf{K}\left(\mathbf{u}^{\prime} \mathbf{K}\right)^{\prime}=0 .$$
But $\mathbf{u}^{\prime} \mathbf{u}$ and $\mathbf{u}^{\prime} \mathbf{K}\left(\mathbf{u}^{\prime} \mathbf{K}\right)^{\prime}$ are both sums of squares of real numbers. Hence their sum is zero only if their elements are, i.e., only if $\mathbf{u}=\mathbf{0}$. This contradicts the assumption. Therefore $\mathbf{I}+\mathbf{K} \mathbf{K}^{\prime}$ has full rank.
Lemma 9. When $\mathbf{B}$ has full row rank $\mathbf{B B}^{\prime}$ is non-singular.
Proof. As in Lemma 7, write $\mathbf{B}=\mathbf{M}\left[\begin{array}{ll}\mathbf{I} & \mathbf{S}\end{array}\right] \mathbf{Q}^{-1}$ where $\mathbf{M}^{-1}$ exists. Then, because $\mathbf{Q}$ is a permutation matrix and thus orthogonal, $\mathbf{B B}^{\prime}=\mathbf{M}\left(\mathbf{I}+\mathbf{S S}^{\prime}\right) \mathbf{M}^{\prime}$ which, by Lemma 8 and because $\mathbf{M}^{-1}$ exists, is non-singular.
Corollary. When $\mathbf{B}$ has full column rank $\mathbf{B}^{\prime} \mathbf{B}$ is non-singular.
Consider now a matrix $\mathbf{A}_{p \times e}$ of rank $r$, less than both $p$ and $q$. A contains at least one non-singular minor of order $r$, which we will assume is the leading minor. There is no loss of generality in this assumption because if it is not true, the algorithm of Sec. $1 \mathrm{~b}$ will always yield a generalized inverse of $\mathbf{A}$ from a generalized inverse of $\mathbf{B}=\mathbf{R A S}$ for permutation matrices $\mathbf{R}$ and $\mathbf{S}$, where $\mathbf{B}$ has its leading $r \times r$ minor non-singular. Discussion of generalized inverses of $\mathbf{A}$ is therefore confined to $\mathbf{A}$ having its leading $r \times r$ minor nonsingular.

统计代写|应用线性模型代写Applied Linear Models代考|OTHER RESULTS

Procedures for inverting partitioned matrices are well known [e.g., Searle (1966), Sec. 8.7]. In particular, the inverse of the partitioned full rank symmetric matrix
$$\mathbf{M}=\left[\begin{array}{c} \mathbf{X}^{\prime} \ \mathbf{Z}^{\prime} \end{array}\right]\left[\begin{array}{ll} \mathbf{X} & \mathbf{Z} \end{array}\right]=\left[\begin{array}{cc} \mathbf{X}^{\prime} \mathbf{X} & \mathbf{X}^{\prime} \mathbf{Z} \ \mathbf{Z}^{\prime} \mathbf{X} & \mathbf{Z}^{\prime} \mathbf{Z} \end{array}\right] \equiv\left[\begin{array}{cc} \mathbf{A} & \mathbf{B} \ \mathbf{B}^{\prime} & \mathbf{D} \end{array}\right], \text { say }$$
can, for
$$\mathbf{W}=\left(\mathbf{D}-\mathbf{B}^{\prime} \mathbf{A}^{-1} \mathbf{B}\right)^{-1}=\left[\mathbf{Z}^{\prime} \mathbf{Z}-\mathbf{Z}^{\prime} \mathbf{X}\left(\mathbf{X}^{\prime} \mathbf{X}\right)^{-1} \mathbf{X}^{\prime} \mathbf{Z}\right]^{-1}$$
be written as
\begin{aligned} \mathbf{M}^{-1} &=\left[\begin{array}{cc} \mathbf{A}^{-1}+\mathbf{A}^{-1} \mathbf{B} \mathbf{W B}^{\prime} \mathbf{A}^{-1} & -\mathbf{A}^{-1} \mathbf{B W} \ -\mathbf{W B}^{\prime} \mathbf{A}^{-1} & \mathbf{W} \end{array}\right] \ &=\left[\begin{array}{cc} \mathbf{A}^{-1} & 0 \ 0 & 0 \end{array}\right]+\left[\begin{array}{c} -\mathbf{A}^{-1} \mathbf{B} \ \mathbf{I} \end{array}\right] \mathbf{W}\left[\begin{array}{ll} -\mathbf{B}^{\prime} \mathbf{A}^{-1} & \mathbf{I} \end{array}\right] \end{aligned}
The analogy of (48) for generalized inverses, when $\mathbf{M}$ is symmetric but singular, has been derived by Rohde (1965). On defining $\mathbf{A}^{-}$and $\mathbf{Q}^{-}$as generalized inverses of $\mathbf{A}$ and $\mathbf{Q}$ respectively, where $\mathbf{Q}=\mathbf{D}-\mathbf{B}^{\prime} \mathbf{A}^{-} \mathbf{B}$, then a generalized inverse of $\mathbf{M}$ is
$\mathbf{M}^{-}=\left[\begin{array}{cc}\mathbf{A}^{-}+\mathbf{A}^{-} \mathbf{B} \mathbf{Q}^{-} \mathbf{B}^{\prime} \mathbf{A}^{-} & -\mathbf{A}^{-} \mathbf{B} \mathbf{Q}^{-} \ -\mathbf{Q}^{-} \mathbf{B}^{\prime} \mathbf{A}^{-} & \mathbf{Q}^{-}\end{array}\right]$
$=\left[\begin{array}{cc}\mathbf{A}^{-} & 0 \ 0 & 0\end{array}\right]+\left[\begin{array}{c}-\mathbf{A}^{-} \mathbf{B} \ \mathbf{I}\end{array}\right] \mathbf{Q}^{-}\left[\begin{array}{ll}-\mathbf{B}^{\prime} \mathbf{A}^{-} & \mathbf{I}]\end{array}\right]$
It is to be emphasized that the generalized inverses referred to here are just as have been defined throughout, namely satisfying only the first of Penrose’s four conditions. (In showing that $\mathbf{M M} \mathbf{M}=\mathbf{M}$, considerable use is made of Theorem 7.)

统计代写|应用线性模型代写Applied Linear Models代考|ARBITRARINESS IN A GENERALIZED INVERSE

$\mathbf{B}=\mathbf{R A S}$ 对于置换矩阵 $\mathbf{R}$ 和 $\mathbf{S}$ ， 在哪里 $\mathbf{B}$ 有它的领先地位 $r \times r$ 次要非单数。广义逆的讨论 $\mathbf{A}$ 因此仅限于 $\mathbf{A}$ 有 其领先地位 $r \times r$ 次要的非单数。

统计代写|应用线性模型代写Applied Linear Models代考|OTHER RESULTS

$$\mathbf{W}=\left(\mathbf{D}-\mathbf{B}^{\prime} \mathbf{A}^{-1} \mathbf{B}\right)^{-1}=\left[\mathbf{Z}^{\prime} \mathbf{Z}-\mathbf{Z}^{\prime} \mathbf{X}\left(\mathbf{X}^{\prime} \mathbf{X}\right)^{-1} \mathbf{X}^{\prime} \mathbf{Z}\right]^{-1}$$

$$\mathbf{M}^{-1}=\left[\begin{array}{lll} \mathbf{A}^{-1}+\mathbf{A}^{-1} \mathbf{B} \mathbf{W} \mathbf{B}^{\prime} \mathbf{A}^{-1} & -\mathbf{A}^{-1} \mathbf{B} \mathbf{W}-\mathbf{W \mathbf { B } ^ { \prime }} \mathbf{A}^{-1} & \mathbf{W} \end{array}\right] \quad=\left[\begin{array}{llll} \mathbf{A}^{-1} & 0 & 0 & 0 \end{array}\right]+\left[\begin{array}{l} -\mathbf{A}^{-1} \end{array}\right.$$
(48) 对广义逆的类比，当 $\mathbf{M}$ 是对称但奇异的，由 Rohde (1965) 推导出来。关于定义 $\mathbf{A}^{-}$和 $\mathbf{Q}^{-}$作为广义逆 $\mathbf{A}$ 和 $\mathbf{Q}$ 分别，其中 $\mathbf{Q}=\mathbf{D}-\mathbf{B}^{\prime} \mathbf{A}^{-} \mathbf{B}$ ，然后是的广义逆 $\mathbf{M}$ 是
$\mathbf{M}^{-}=\left[\mathbf{A}^{-}+\mathbf{A}^{-} \mathbf{B} \mathbf{Q}^{-} \mathbf{B}^{\prime} \mathbf{A}^{-} \quad-\mathbf{A}^{-} \mathbf{B} \mathbf{Q}^{-}-\mathbf{Q}^{-} \mathbf{B}^{\prime} \mathbf{A}^{-} \quad \mathbf{Q}^{-}\right]$

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有限元方法代写

tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。

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MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。

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The graphs above are incomplete. These figures only show a vertex with degree four (vertex E), its nearest neighbors (A, B, C, and D), and segments of A-C Kempe chains. The entire graphs would also contain several other vertices (especially, more colored the same as B or D) and enough edges to be MPG’s. The left figure has A connected to $C$ in a single section of an A-C Kempe chain (meaning that the vertices of this chain are colored the same as A and C). The left figure shows that this A-C Kempe chain prevents B from connecting to $\mathrm{D}$ with a single section of a B-D Kempe chain. The middle figure has A and C in separate sections of A-C Kempe chains. In this case, B could connect to D with a single section of a B-D Kempe chain. However, since the A and C of the vertex with degree four lie on separate sections, the color of C’s chain can be reversed so that in the vertex with degree four, C is effectively recolored to match A’s color, as shown in the right figure. Similarly, D’s section could be reversed in the left figure so that D is effectively recolored to match B’s color.

Kempe also attempted to demonstrate that vertices with degree five are fourcolorable in his attempt to prove the four-color theorem [Ref. 2], but his argument for vertices with degree five was shown by Heawood in 1890 to be insufficient [Ref. 3]. Let’s explore what happens if we attempt to apply our reasoning for vertices with degree four to a vertex with degree five.

数学代写|图论作业代写Graph Theory代考|The previous diagrams

The previous diagrams show that when the two color reversals are performed one at a time in the crossed-chain graph, the first color reversal may break the other chain, allowing the second color reversal to affect the colors of one of F’s neighbors. When we performed the $2-4$ reversal to change B from 2 to 4 , this broke the 1-4 chain. When we then performed the 2-3 reversal to change E from 3, this caused C to change from 3 to 2 . As a result, F remains connected to four different colors; this wasn’t reversed to three as expected.
Unfortunately, you can’t perform both reversals “at the same time” for the following reason. Let’s attempt to perform both reversals “at the same time.” In this crossed-chain diagram, when we swap 2 and 4 on B’s side of the 1-3 chain, one of the 4’s in the 1-4 chain may change into a 2, and when we swap 2 and 3 on E’s side of the 1-4 chain, one of the 3’s in the 1-3 chain may change into a 2 . This is shown in the following figure: one 2 in each chain is shaded gray. Recall that these figures are incomplete; they focus on one vertex (F), its neighbors (A thru E), and Kempe chains. Other vertices and edges are not shown.

Note how one of the 3’s changed into 2 on the left. This can happen when we reverse $\mathrm{C}$ and $\mathrm{E}$ (which were originally 3 and 2 ) on E’s side of the 1-4 chain. Note also how one of the 4’s changed into 2 on the right. This can happen when we reverse B and D (which were originally 2 and 4) outside of the 1-3 chain. Now we see where a problem can occur when attempting to swap the colors of two chains at the same time. If these two 2’s happen to be connected by an edge like the dashed edge shown above, if we perform the double reversal at the same time, this causes two vertices of the same color to share an edge, which isn’t allowed. We’ll revisit Kempe’s strategy for coloring a vertex with degree five in Chapter $25 .$

数学代写|图论作业代写Graph Theory代考|The shading of one section of the B-R

• MPG 是三角测量的。它由具有三个边和三个顶点的面组成。
• 每个面的三个顶点必须是三种不同的颜色。
• 每条边由两个相邻的三角形共享，形成一个四边形。
• 每个四边形将有 3 或 4 种不同的颜色。如果与共享边相对的两个顶点恰好是相同的颜色，则它有 3 种颜色。
• 对于每个四边形，四个顶点中的至少 1 个顶点和最多 3 个顶点具有任何颜色对的颜色。例如，具有 R、G、B 和G有 1 个顶点R−是和3个顶点乙−G，或者您可以将其视为 1 个顶点乙−是和3个顶点G−R，或者您可以将其视为 BR 的 2 个顶点和 GY 的 2 个顶点。在后一种情况下，2G’ 不是同一链的连续颜色。
• 当您将更多三角形组合在一起（四边形仅组合两个）并考虑可能的颜色时，您将看到 Kempe 的部分

• 画一张R顶点和一个是由边连接的顶点。
• 如果一个新顶点连接到这些顶点中的每一个，它必须是乙或者G.
• 如果一个新顶点连接到 R 而不是是，可能是是,乙， 或者G.
• 如果一个新的顶点连接到是但不是R，可能是R,乙， 或者G.
• RY 链要么继续增长，要么被 B 包围，G.
• 如果你关注 B 和 G，你会为它的链条得出类似的结论。
• 如果一条链条完全被其对应物包围，则链条的新部分可能会出现在其对应物的另一侧。
Kempe 证明了所有具有四阶的顶点（那些恰好连接到其他四个顶点的顶点）都是四色的 [Ref. 2]。例如，考虑下面的中心顶点。

数学代写|图论作业代写Graph Theory代考|In the previous figure

• A 和 C 或者是 AC Kempe 链的同一部分的一部分，或者它们各自位于 AC Kempe 链的不同部分。（如果一种和C例如，是红色和黄色的，则 AC 链是红黄色链。） – 如果一种和C每个位于 AC Kempe 链的不同部分，其中一个部分的颜色可以反转，这有效地重新着色 C 以匹配 A 的颜色。如果 A 和 C 是 AC Kempe 链的同一部分的一部分，则 B 和 D每个都必须位于 BD Kempe 链的不同部分，因为 AC Kempe 链将阻止任何 BD Kempe 链从 B 到达 D。（如果乙和D是蓝色和绿色，例如，那么一种BD Kempe 链是蓝绿色链。）在这种情况下，由于 B 和 D 分别位于 BD Kempe 链的不同部分，因此 BD Kempe 链的其中一个部分的颜色可以反转，这有效地重新着色 D 以匹配 B颜色。– 因此，可以使 C 与 A 具有相同的颜色或使 D 具有与 A 相同的颜色乙通过反转 Kempe 链的分离部分。

Kempe 还试图证明五阶顶点是可四色的，以证明四色定理 [Ref. 2]，但 Heawood 在 1890 年证明他关于五次顶点的论点是不充分的 [Ref. 3]。让我们探讨一下如果我们尝试将我们对度数为四的顶点的推理应用于度数为五的顶点会发生什么。

有限元方法代写

tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。

MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。

统计代写|应用线性模型代写Applied Linear Models代考|STAT6420

statistics-lab™ 为您的留学生涯保驾护航 在代写应用线性模型Applied Linear Models方面已经树立了自己的口碑, 保证靠谱, 高质且原创的统计Statistics代写服务。我们的专家在代写应用线性模型Applied Linear Models代写方面经验极为丰富，各种代写应用线性模型Applied Linear Models相关的作业也就用不着说。

• Statistical Inference 统计推断
• Statistical Computing 统计计算
• (Generalized) Linear Models 广义线性模型
• Statistical Machine Learning 统计机器学习
• Longitudinal Data Analysis 纵向数据分析
• Foundations of Data Science 数据科学基础

统计代写|应用线性模型代写Applied Linear Models代考|Properties of solutions

One might now ask about the relationship, if any, between the two solutions (9) and (12) found by using the two generalized inverses $\mathbf{G}$ and $\dot{\mathbf{G}}$. Both satisfy (8) for an infinite number of sets of values of $z_3, z_4$ and $\dot{z}_1, \dot{z}_4$. The basic question is: Do the two solutions generate, through allocating different sets of values to the arbitrary values $z_3$ and $z_4$ in $\tilde{\mathbf{x}}$ and $\dot{z}_1$ and $\dot{z}_4$ in $\dot{\mathbf{x}}$, the same series of vectors that satisfy $\mathbf{A x}=\mathbf{y}$ ? The answer is “yes”. This is so because, on putting $\dot{z}_1=-6+z_3+29 z_4$ and $\dot{z}_4=z_4$, the solution in (12) becomes identical to that in (9). Hence (9) and (12) both generate the same sets of solutions to (8)

The relationship between solutions using $\mathbf{G}$ and those using $\dot{\mathbf{G}}$ is that, on putting
$$\tilde{\mathbf{x}} \text { reduces to } \dot{\mathbf{x}} \quad \mathbf{z}=(\mathbf{G}-\dot{\mathbf{G}}) \mathbf{y}+(\mathbf{I}-\dot{\mathbf{G} A}) \dot{\mathbf{z}},$$
A stronger result, which concerns generation of all solutions from $\tilde{\mathbf{x}}$, is contained in the following theorem.

Theorem 3. For the consistent equations $\mathbf{A x}=\mathbf{y}$ all solutions are, for any specific G, generated by $\tilde{\mathbf{x}}=\mathbf{G y}+(\mathbf{G A}-\mathbf{I}) \mathbf{z}$, for arbitrary $\mathbf{z}$.

Proof. Let $\mathbf{x}^$ be any solution to $\mathbf{A x}=\mathbf{y}$. Choose $\mathbf{z}=(\mathbf{G A}-\mathbf{I}) \mathbf{x}^$ and it will be found that $\tilde{\mathbf{x}}$ reduces to $\mathbf{x}^*$. Thus, by appropriate choice of $\mathbf{z}$, any solution to $\mathbf{A x}=\mathbf{y}$ can be put in the form of $\tilde{\mathbf{x}}$.

The importance of this theorem is that one need derive only one generalized inverse of $\mathbf{A}$ in order to be able to generate all solutions to $\mathbf{A x}=\mathbf{y}$. There are no solutions other than those that can be generated from $\tilde{\mathbf{x}}$.

Having established a method for solving linear equations and shown that they can have an infinite number of solutions, we ask two questions: What relationships exist among the solutions and to what extent are the solutions linearly independent (LIN)? Since each solution is a vector of order $q$ there can, of course, be no more than $q$ LIN solutions. In fact there are fewer, as Theorem 4 shows. But first, a lemma.

统计代写|应用线性模型代写Applied Linear Models代考|OTHER DEFINITIONS

It is clear that the Penrose inverse $\mathbf{K}$ is not easy to compute, especially when $\mathbf{A}$ has many columns, because then the application of the Cayley-Hamilton theorem to $\mathbf{A}^{\prime} \mathbf{A}$ for obtaining $\mathbf{T}$ will be tedious. However, as has already been shown, only the first Penrose condition needs to be satisfied in order to have a matrix useful for solving linear equations. And in pursuing the topic of linear models it is found that this is the only condition really needed. It is for this reason that a generalized inverse of $\mathbf{A}$ has been defined as any matrix $\mathbf{G}$ that satisfies AGA = A, a definition that is retained throughout this book. Nevertheless, a variety of names are to be found in the literature, both for $\mathbf{G}$ and for other matrices satisfying fewer than all four of the Penrose conditions. A set of descriptive names is given in Table $1.1$.

In the notation of Table $1.1 \mathbf{A}^{(0)}=\mathbf{G}$, the generalized inverse already defined and discussed, and $\mathbf{A}^{(p)}=\mathbf{K}$, the Penrose inverse. This has also been called the pseudo inverse and the $p$-inverse by various authors. The suggested definition of a normalized generalized inverse in Table $1.1$ is not universally accepted. As given there, it is used by Urquhart (1968), whereas Goldman and Zelen (1964) call it a “weak” generalized inverse. An example of such a matrix is a left inverse $\mathbf{L}$ such that $\mathbf{L A}=\mathbf{I}$. The description “normalized” has also been used by Rohde (1966) for a matrix satisfying conditions (i), (ii) and (iv). An example of this kind of matrix is the right inverse $\mathbf{R}$ for which $\mathbf{A R}=\mathbf{I}$.
Using the symbols of Table $1.1$ it can be seen that
$$\mathbf{A}^{(g)} \supset \mathbf{A}^{(r)} \supset \mathbf{A}^{(n)} \supset \mathbf{A}^{(p)}$$ namely that the set of matrices $\mathbf{A}^{(g)}$ includes all those that are reflexive, $\mathbf{A}^{(r)}$, which in turn includes all the normalized generalized inverses $\mathbf{A}^{(n)}$, which includes the unique $\mathbf{A}^{(p)}=\mathbf{K}$. Relationships between the four can be established as follows:
\begin{aligned} \mathbf{A}^{(r)} &=\mathbf{A}^{(g)} \mathbf{A} \mathbf{A}^{(g)} \ \mathbf{A}^{(n)} &=\mathbf{A}^{\prime}\left(\mathbf{A A}^{\prime}\right)^{(g)} \ \mathbf{A}^{(p)} &=\mathbf{A}^{\prime}\left(\mathbf{A A}^{\prime}\right)^{(g)} \mathbf{A}\left(\mathbf{A}^{\prime} \mathbf{A}\right)^{(g)} \mathbf{A}^{\prime} . \end{aligned}

统计代写|应用线性模型代写Applied Linear Models代考|Properties of solutions

$$\tilde{\mathbf{x}} \text { reduces to } \dot{\mathbf{x}} \quad \mathbf{z}=(\mathbf{G}-\dot{\mathbf{G}}) \mathbf{y}+(\mathbf{I}-\mathbf{G} A) \dot{\mathbf{z}},$$

统计代写|应用线性模型代写Applied Linear Models代考|OTHER DEFINITIONS

$$\mathbf{A}^{(g)} \supset \mathbf{A}^{(r)} \supset \mathbf{A}^{(n)} \supset \mathbf{A}^{(p)}$$

$$\mathbf{A}^{(r)}=\mathbf{A}^{(g)} \mathbf{A} \mathbf{A}^{(g)} \mathbf{A}^{(n)} \quad=\mathbf{A}^{\prime}\left(\mathbf{A} \mathbf{A}^{\prime}\right)^{(g)} \mathbf{A}^{(p)}=\mathbf{A}^{\prime}\left(\mathbf{A} \mathbf{A}^{\prime}\right)^{(g)} \mathbf{A}\left(\mathbf{A}^{\prime} \mathbf{A}\right)^{(g)} \mathbf{A}^{\prime}$$

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有限元方法代写

tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。

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MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。

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The graphs above are incomplete. These figures only show a vertex with degree four (vertex E), its nearest neighbors (A, B, C, and D), and segments of A-C Kempe chains. The entire graphs would also contain several other vertices (especially, more colored the same as B or D) and enough edges to be MPG’s. The left figure has A connected to $C$ in a single section of an A-C Kempe chain (meaning that the vertices of this chain are colored the same as A and C). The left figure shows that this A-C Kempe chain prevents B from connecting to $\mathrm{D}$ with a single section of a B-D Kempe chain. The middle figure has A and C in separate sections of A-C Kempe chains. In this case, B could connect to D with a single section of a B-D Kempe chain. However, since the A and C of the vertex with degree four lie on separate sections, the color of C’s chain can be reversed so that in the vertex with degree four, C is effectively recolored to match A’s color, as shown in the right figure. Similarly, D’s section could be reversed in the left figure so that D is effectively recolored to match B’s color.

Kempe also attempted to demonstrate that vertices with degree five are fourcolorable in his attempt to prove the four-color theorem [Ref. 2], but his argument for vertices with degree five was shown by Heawood in 1890 to be insufficient [Ref. 3]. Let’s explore what happens if we attempt to apply our reasoning for vertices with degree four to a vertex with degree five.

数学代写|图论作业代写Graph Theory代考|The previous diagrams

The previous diagrams show that when the two color reversals are performed one at a time in the crossed-chain graph, the first color reversal may break the other chain, allowing the second color reversal to affect the colors of one of F’s neighbors. When we performed the $2-4$ reversal to change B from 2 to 4 , this broke the 1-4 chain. When we then performed the 2-3 reversal to change E from 3, this caused C to change from 3 to 2 . As a result, F remains connected to four different colors; this wasn’t reversed to three as expected.
Unfortunately, you can’t perform both reversals “at the same time” for the following reason. Let’s attempt to perform both reversals “at the same time.” In this crossed-chain diagram, when we swap 2 and 4 on B’s side of the 1-3 chain, one of the 4’s in the 1-4 chain may change into a 2, and when we swap 2 and 3 on E’s side of the 1-4 chain, one of the 3’s in the 1-3 chain may change into a 2 . This is shown in the following figure: one 2 in each chain is shaded gray. Recall that these figures are incomplete; they focus on one vertex (F), its neighbors (A thru E), and Kempe chains. Other vertices and edges are not shown.

Note how one of the 3’s changed into 2 on the left. This can happen when we reverse $\mathrm{C}$ and $\mathrm{E}$ (which were originally 3 and 2 ) on E’s side of the 1-4 chain. Note also how one of the 4’s changed into 2 on the right. This can happen when we reverse B and D (which were originally 2 and 4) outside of the 1-3 chain. Now we see where a problem can occur when attempting to swap the colors of two chains at the same time. If these two 2’s happen to be connected by an edge like the dashed edge shown above, if we perform the double reversal at the same time, this causes two vertices of the same color to share an edge, which isn’t allowed. We’ll revisit Kempe’s strategy for coloring a vertex with degree five in Chapter $25 .$

数学代写|图论作业代写Graph Theory代考|The shading of one section of the B-R

• MPG 是三角测量的。它由具有三个边和三个顶点的面组成。
• 每个面的三个顶点必须是三种不同的颜色。
• 每条边由两个相邻的三角形共享，形成一个四边形。
• 每个四边形将有 3 或 4 种不同的颜色。如果与共享边相对的两个顶点恰好是相同的颜色，则它有 3 种颜色。
• 对于每个四边形，四个顶点中的至少 1 个顶点和最多 3 个顶点具有任何颜色对的颜色。例如，具有 R、G、B 和G有 1 个顶点R−是和3个顶点乙−G，或者您可以将其视为 1 个顶点乙−是和3个顶点G−R，或者您可以将其视为 BR 的 2 个顶点和 GY 的 2 个顶点。在后一种情况下，2G’ 不是同一链的连续颜色。
• 当您将更多三角形组合在一起（四边形仅组合两个）并考虑可能的颜色时，您将看到 Kempe 的部分

• 画一张R顶点和一个是由边连接的顶点。
• 如果一个新顶点连接到这些顶点中的每一个，它必须是乙或者G.
• 如果一个新顶点连接到 R 而不是是，可能是是,乙， 或者G.
• 如果一个新的顶点连接到是但不是R，可能是R,乙， 或者G.
• RY 链要么继续增长，要么被 B 包围，G.
• 如果你关注 B 和 G，你会为它的链条得出类似的结论。
• 如果一条链条完全被其对应物包围，则链条的新部分可能会出现在其对应物的另一侧。
Kempe 证明了所有具有四阶的顶点（那些恰好连接到其他四个顶点的顶点）都是四色的 [Ref. 2]。例如，考虑下面的中心顶点。

数学代写|图论作业代写Graph Theory代考|In the previous figure

• A 和 C 或者是 AC Kempe 链的同一部分的一部分，或者它们各自位于 AC Kempe 链的不同部分。（如果一种和C例如，是红色和黄色的，则 AC 链是红黄色链。） – 如果一种和C每个位于 AC Kempe 链的不同部分，其中一个部分的颜色可以反转，这有效地重新着色 C 以匹配 A 的颜色。如果 A 和 C 是 AC Kempe 链的同一部分的一部分，则 B 和 D每个都必须位于 BD Kempe 链的不同部分，因为 AC Kempe 链将阻止任何 BD Kempe 链从 B 到达 D。（如果乙和D是蓝色和绿色，例如，那么一种BD Kempe 链是蓝绿色链。）在这种情况下，由于 B 和 D 分别位于 BD Kempe 链的不同部分，因此 BD Kempe 链的其中一个部分的颜色可以反转，这有效地重新着色 D 以匹配 B颜色。– 因此，可以使 C 与 A 具有相同的颜色或使 D 具有与 A 相同的颜色乙通过反转 Kempe 链的分离部分。

Kempe 还试图证明五阶顶点是可四色的，以证明四色定理 [Ref. 2]，但 Heawood 在 1890 年证明他关于五次顶点的论点是不充分的 [Ref. 3]。让我们探讨一下如果我们尝试将我们对度数为四的顶点的推理应用于度数为五的顶点会发生什么。

有限元方法代写

tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。

MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。

统计代写|应用线性模型代写Applied Linear Models代考|STAT3022

statistics-lab™ 为您的留学生涯保驾护航 在代写应用线性模型Applied Linear Models方面已经树立了自己的口碑, 保证靠谱, 高质且原创的统计Statistics代写服务。我们的专家在代写应用线性模型Applied Linear Models代写方面经验极为丰富，各种代写应用线性模型Applied Linear Models相关的作业也就用不着说。

• Statistical Inference 统计推断
• Statistical Computing 统计计算
• (Generalized) Linear Models 广义线性模型
• Statistical Machine Learning 统计机器学习
• Longitudinal Data Analysis 纵向数据分析
• Foundations of Data Science 数据科学基础

统计代写|应用线性模型代写Applied Linear Models代考|GENERALIZED INVERSE MATRICES

The application of generalized inverse matrices to linear statistical models is of relatively recent occurrence. As a mathematical tool such matrices aid in understanding certain aspects of the analysis procedures associated with linear models, especially the analysis of unbalanced data, a topic to which considerable attention is given in this book. An appropriate starting point is therefore a summary of the features of generalized inverse matrices that are important to linear models. Other ancillary results in matrix algebra are also discussed.
a. Definition and existence
A generalized inverse of a matrix $\mathbf{A}$ is defined, in this book, as any matrix $\mathbf{G}$ that satisfies the equation
$$\mathbf{A G A}=\mathbf{A} .$$
The name “generalized inverse” for matrices $\mathbf{G}$ defined by (1) is unfortunately not universally accepted, although it is used quite widely. Names such as “conditional inverse”, “pseudo inverse” and ” $g$-inverse” are also to be found in the literature, sometimes for matrices defined as is $\mathbf{G}$ of (1) and sometimes for matrices defined as variants of G. However, throughout this book the name “generalized inverse” of $\mathbf{A}$ is used exclusively for any matrix $\mathbf{G}$ satisfying (1).

Notice that (1) does not define $\mathbf{G}$ as “the” generalized inverse of $\mathbf{A}$ but as ” $a$ ” generalized inverse. This is because $\mathbf{G}$, for a given matrix $\mathbf{A}$, is not unique. As shown below, there is an infinite number of matrices $\mathbf{G}$ that satisfy (1) and so we refer to the whole class of them as generalized inverses of $\mathbf{A}$.

One way of illustrating the existence of $\mathbf{G}$ and its non-uniqueness starts with the equivalent diagonal form of $\mathbf{A}$. If $\mathbf{A}$ has order $p \times q$ the reduction to this diagonal form can be written as
$$\mathbf{P}{p \times p} \mathbf{A}{p \times q} \mathbf{Q}{q \times q}=\boldsymbol{\Delta}{p \times q} \equiv\left[\begin{array}{cl} \mathbf{D}{r \times r} & \mathbf{0}{r \times(q-r)} \ \mathbf{0}{(p-r) \times r} & \mathbf{0}{(p-r) \times(q-r)} \end{array}\right]$$
or, more simply, as
$$\mathbf{P A Q}=\Delta=\left[\begin{array}{cc} \mathbf{D}_r & 0 \ 0 & 0 \end{array}\right] .$$

统计代写|应用线性模型代写Applied Linear Models代考|Obtaining solutions

The link between a generalized inverse of the matrix $\mathbf{A}$ and consistent equations $\mathbf{A x}=\mathbf{y}$ is set out in the following theorem adapted from Rao (1962)

Theorem 1. Consistent equations $\mathbf{A x}=\mathbf{y}$ have a solution $\mathbf{x}=\mathbf{G y}$ if and only if $\mathbf{A G A}=\mathbf{A}$.

Proof. If the equations $\mathbf{A x}=\mathbf{y}$ are consistent and have $\mathbf{x}=\mathbf{G y}$ as a solution, write $\mathbf{a}_j$ for the $j$ th column of $\mathbf{A}$ and consider the equations $\mathbf{A x}=\mathbf{a}_j$. They have a solution: the null vector with its jth element set equal to unity. Therefore the equations $\mathbf{A x}=\mathbf{a}_j$ are consistent. Furthermore, since consistent equations $\mathbf{A x}=\mathbf{y}$ have a solution $\mathbf{x}=\mathbf{G y}$, it follows that consistent equations $\mathbf{A x}=\mathbf{a}_j$ have a solution $\mathbf{x}=\mathbf{G a}_j$. Therefore $\mathbf{A G a} \mathbf{a}_j=\mathbf{a}_j$; and this is true for all values of $j$, i.e., for all columns of $\mathbf{A}$. Hence $\mathbf{A G A}=\mathbf{A}$.

Conversely, if $\mathbf{A G A}=\mathbf{A}$, then $\mathbf{A G} \mathbf{A x}=\mathbf{A x}$, and when $\mathbf{A x}=\mathbf{y}$ this gives $\mathbf{A G y}=\mathbf{y}$, i.e., $\mathbf{A}(\mathbf{G} \mathbf{y})=\mathbf{y}$. Hence $\mathbf{x}=\mathbf{G y}$ is a solution of $\mathbf{A x}=\mathbf{y}$, and the theorem is proved.

Theorem 1 indicates how a solution to consistent equations may be obtained: find any matrix $\mathbf{G}$ satisfying $\mathbf{A G A}=\mathbf{A}$, i.e., find $\mathbf{G}$ as any generalized inverse of $\mathbf{A}$, and then $\mathbf{G y}$ is a solution. However, as Theorem 2 shows, Gy is not the only solution. There are, indeed, many solutions whenever $\mathbf{A}$ is anything other than a square, non-singular matrix.

Theorem 2. If $\mathbf{A}$ has $q$ columns and if $\mathbf{G}$ is a generalized inverse of $\mathbf{A}$, then the consistent equations $\mathbf{A x}=\mathbf{y}$ have solution
$$\tilde{\mathbf{x}}=\mathbf{G y}+(\mathbf{G A}-\mathbf{I}) \mathbf{z},$$
where $\mathbf{z}$ is any arbitrary vector of order $q$.
Proof. $\mathbf{A} \tilde{\mathbf{x}}=\mathbf{A G} \mathbf{y}+(\mathbf{A G A}-\mathbf{A}) \mathbf{z}$
\begin{aligned} &=\mathbf{A G y}, \text { because } \mathbf{A} \mathbf{G A}=\mathbf{A}, \ &=\mathbf{y}, \text { by Theorem } 1 ; \end{aligned}
i.e., $\tilde{\mathbf{x}}$ satisfies $\mathbf{A x}=\mathbf{y}$ and hence is a solution. The notation $\tilde{\mathbf{x}}$ emphasizes that $\tilde{\mathbf{x}}$ is a solution, distinguishing it from the general vector of unknowns $\mathbf{x}$.
Note that the solution $\tilde{\mathbf{x}}$ involves an element of arbitrariness because $\mathbf{z}$ is an arbitrary vector: $\mathbf{z}$ can have any value at all and $\tilde{\mathbf{x}}$ will still be a solution to $\mathbf{A x}=\mathbf{y}$. No matter what value is given to $\mathbf{z}$, the expression for $\tilde{\mathbf{x}}$ given in (7) satisfies $\mathbf{A x}=\mathbf{y}$. Furthermore, this will be so for whatever generalized inverse of $\mathbf{A}$ is used for $\mathbf{G}$

统计代写|应用线性模型代写Applied Linear Models代考|GENERALIZED INVERSE MATRICES

$$\mathbf{A} \mathbf{G} \mathbf{A}=\mathbf{A} \text {. }$$

$$\mathbf{P A} \mathbf{Q}=\Delta=\left[\begin{array}{llll} \mathbf{D}_r & 0 & 0 & 0 \end{array}\right]$$

统计代写|应用线性模型代写Applied Linear Models代考|Obtaining solutions

$$\tilde{\mathbf{x}}=\mathbf{G y}+(\mathbf{G A}-\mathbf{I}) \mathbf{z},$$

$=\mathbf{A} \mathbf{G}$, because $\mathbf{A} \mathbf{G} \mathbf{A}=\mathbf{A}, \quad=\mathbf{y}$, by Theorem $1 ;$ 请注意，解决方案 $\tilde{\mathbf{x}}$ 涉及任意因素，因为 $\mathbf{z}$ 是一个任意向量: $\mathbf{z}$ 可以有任何价值，并且 $\tilde{\mathbf{x}}$ 仍将是一个解决方案 $\mathbf{A x}=\mathbf{y}$. 不管赋矛什么价值 $\mathbf{z}$ ，表达式为 $\tilde{\mathbf{x}}(7)$ 中给出的满足 $\mathbf{A} \mathbf{x}=\mathbf{y}$. 此外，对于任何广义逆 $\mathbf{A}$ 是用来 $\mathbf{G}$

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有限元方法代写

tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。

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MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。

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The graphs above are incomplete. These figures only show a vertex with degree four (vertex E), its nearest neighbors (A, B, C, and D), and segments of A-C Kempe chains. The entire graphs would also contain several other vertices (especially, more colored the same as B or D) and enough edges to be MPG’s. The left figure has A connected to $C$ in a single section of an A-C Kempe chain (meaning that the vertices of this chain are colored the same as A and C). The left figure shows that this A-C Kempe chain prevents B from connecting to $\mathrm{D}$ with a single section of a B-D Kempe chain. The middle figure has A and C in separate sections of A-C Kempe chains. In this case, B could connect to D with a single section of a B-D Kempe chain. However, since the A and C of the vertex with degree four lie on separate sections, the color of C’s chain can be reversed so that in the vertex with degree four, C is effectively recolored to match A’s color, as shown in the right figure. Similarly, D’s section could be reversed in the left figure so that D is effectively recolored to match B’s color.

Kempe also attempted to demonstrate that vertices with degree five are fourcolorable in his attempt to prove the four-color theorem [Ref. 2], but his argument for vertices with degree five was shown by Heawood in 1890 to be insufficient [Ref. 3]. Let’s explore what happens if we attempt to apply our reasoning for vertices with degree four to a vertex with degree five.

数学代写|图论作业代写Graph Theory代考|The previous diagrams

The previous diagrams show that when the two color reversals are performed one at a time in the crossed-chain graph, the first color reversal may break the other chain, allowing the second color reversal to affect the colors of one of F’s neighbors. When we performed the $2-4$ reversal to change B from 2 to 4 , this broke the 1-4 chain. When we then performed the 2-3 reversal to change E from 3, this caused C to change from 3 to 2 . As a result, F remains connected to four different colors; this wasn’t reversed to three as expected.
Unfortunately, you can’t perform both reversals “at the same time” for the following reason. Let’s attempt to perform both reversals “at the same time.” In this crossed-chain diagram, when we swap 2 and 4 on B’s side of the 1-3 chain, one of the 4’s in the 1-4 chain may change into a 2, and when we swap 2 and 3 on E’s side of the 1-4 chain, one of the 3’s in the 1-3 chain may change into a 2 . This is shown in the following figure: one 2 in each chain is shaded gray. Recall that these figures are incomplete; they focus on one vertex (F), its neighbors (A thru E), and Kempe chains. Other vertices and edges are not shown.

Note how one of the 3’s changed into 2 on the left. This can happen when we reverse $\mathrm{C}$ and $\mathrm{E}$ (which were originally 3 and 2 ) on E’s side of the 1-4 chain. Note also how one of the 4’s changed into 2 on the right. This can happen when we reverse B and D (which were originally 2 and 4) outside of the 1-3 chain. Now we see where a problem can occur when attempting to swap the colors of two chains at the same time. If these two 2’s happen to be connected by an edge like the dashed edge shown above, if we perform the double reversal at the same time, this causes two vertices of the same color to share an edge, which isn’t allowed. We’ll revisit Kempe’s strategy for coloring a vertex with degree five in Chapter $25 .$

数学代写|图论作业代写Graph Theory代考|The shading of one section of the B-R

• MPG 是三角测量的。它由具有三个边和三个顶点的面组成。
• 每个面的三个顶点必须是三种不同的颜色。
• 每条边由两个相邻的三角形共享，形成一个四边形。
• 每个四边形将有 3 或 4 种不同的颜色。如果与共享边相对的两个顶点恰好是相同的颜色，则它有 3 种颜色。
• 对于每个四边形，四个顶点中的至少 1 个顶点和最多 3 个顶点具有任何颜色对的颜色。例如，具有 R、G、B 和G有 1 个顶点R−是和3个顶点乙−G，或者您可以将其视为 1 个顶点乙−是和3个顶点G−R，或者您可以将其视为 BR 的 2 个顶点和 GY 的 2 个顶点。在后一种情况下，2G’ 不是同一链的连续颜色。
• 当您将更多三角形组合在一起（四边形仅组合两个）并考虑可能的颜色时，您将看到 Kempe 的部分

• 画一张R顶点和一个是由边连接的顶点。
• 如果一个新顶点连接到这些顶点中的每一个，它必须是乙或者G.
• 如果一个新顶点连接到 R 而不是是，可能是是,乙， 或者G.
• 如果一个新的顶点连接到是但不是R，可能是R,乙， 或者G.
• RY 链要么继续增长，要么被 B 包围，G.
• 如果你关注 B 和 G，你会为它的链条得出类似的结论。
• 如果一条链条完全被其对应物包围，则链条的新部分可能会出现在其对应物的另一侧。
Kempe 证明了所有具有四阶的顶点（那些恰好连接到其他四个顶点的顶点）都是四色的 [Ref. 2]。例如，考虑下面的中心顶点。

数学代写|图论作业代写Graph Theory代考|In the previous figure

• A 和 C 或者是 AC Kempe 链的同一部分的一部分，或者它们各自位于 AC Kempe 链的不同部分。（如果一种和C例如，是红色和黄色的，则 AC 链是红黄色链。） – 如果一种和C每个位于 AC Kempe 链的不同部分，其中一个部分的颜色可以反转，这有效地重新着色 C 以匹配 A 的颜色。如果 A 和 C 是 AC Kempe 链的同一部分的一部分，则 B 和 D每个都必须位于 BD Kempe 链的不同部分，因为 AC Kempe 链将阻止任何 BD Kempe 链从 B 到达 D。（如果乙和D是蓝色和绿色，例如，那么一种BD Kempe 链是蓝绿色链。）在这种情况下，由于 B 和 D 分别位于 BD Kempe 链的不同部分，因此 BD Kempe 链的其中一个部分的颜色可以反转，这有效地重新着色 D 以匹配 B颜色。– 因此，可以使 C 与 A 具有相同的颜色或使 D 具有与 A 相同的颜色乙通过反转 Kempe 链的分离部分。

Kempe 还试图证明五阶顶点是可四色的，以证明四色定理 [Ref. 2]，但 Heawood 在 1890 年证明他关于五次顶点的论点是不充分的 [Ref. 3]。让我们探讨一下如果我们尝试将我们对度数为四的顶点的推理应用于度数为五的顶点会发生什么。

有限元方法代写

tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。

MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。