77范文网 - 专业文章范例文档资料分享平台

2014年美国大学生数学建模比赛获奖论文-F奖(8)

来源:网络收集 时间:2021-09-24 下载这篇文档 手机版
说明:文章内容仅供预览,部分内容可能不全,需要完整文档或者需要复制内容,请下载word后使用。下载word有问题请添加微信号:或QQ: 处理(尽可能给您提供完整文档),感谢您的支持与谅解。点击这里给我发消息

To extract the information about news reports on the triumph of a certain coach from the search engine, first, we use Wordnet[18] as our tool to obtain a host of synonyms of the word winning , the result is:

booming; flourishing; palmy; prospering; prosperous; roaring; thriving; in; made; no-hit; productive; self-made; sure-fire; triple-crown; victorious; successful

Using these words as our alternative keywords , we can obtain the numbers of winning search results ui for coach i.

The result turns out to be an indication that the ratio between winning search results and overall search results is negatively correlated with the degree of reputation. That is, the higher reputation one coach gets, the more likely the mass media will concentrate on the other aspects of life of this coach. According to this rule, we establish a function of ICR:

4.3.3. The individual influence vector

The individual influence vector l can be interpreted as the overall search results modified by ICT and ICR.

li

The individual influence vector gives an accurate estimation of the media attention certain coach got. It is a normalized vector, so that we can conveniently put it into use in the later section.

4.4. The Cross-Reference Matrix

With the help of the Google search engine, the degree of correlation of two coaches can be measured by the number of search results using two names as Citation Keywords [17] simultaneously. And we define the original cross-reference matrix Z. The entries of the matrix is:

Since exchange of the two names does not affect the result, the matrix Z is symmetrical. And we set all of the diagonal elements of this matrix to be 0.

mo.crotha.mww w模数

a

ICRi(influence coefficient of reputation)=1 i i 1,2, ,n

ui

2

ai ICTi ICRi

j

j

a ICT ICR

j 1

i 1,2, ,n (9)

j

Zij=number of search results number of coach i and coach j

帮助准备美赛同学作参考

4.4.1. The weight function

The elements of cross-reference matrix are influenced by the distinct period of time and reputation. However, things get a bit more complicated here: if two coaches exist in the same period of time, then there could be more reports on competitions they engaged. The competition reports are the redundant information that we want to avoid. What we are aiming to do is to evaluate a certain coach s impact over the span of the sports history and to rule out the redundant information. To do that, we assign a lower weight to the

matrix element in which the two coaches is in the same period of time, and a higher weight to those in a different period of time.

First, let ti and tj to be the characteristic year of two coaches, we want to construct a weight function related to ti and tj. Because we previously set the diagonal elements to be 0, the weight on the diagonal can be zeros. Assuming that the average term of office is 2σ, according to the 2σ principle[3], there is little likelihood that the two coaches can encounter each other in the sport games. Then the corresponding weight can be approximate to be 1 outside the interval 2σ. By carefully weighing the pros and cons of diverse types of function, we establish the original weight function as

Additionally, to take into consideration of ICT, we simply transform the one variable function IIT to two variable function multiplied by the original weight function. The final weight function WF is:

WF=

1 ekti ktj b22

(ti tj)22

From (10), the values of the function in intervals (1910, 2010), (1910, 2010) are drawn in

3D graph as showed in Figure 8 and Figure 9.

Figure 8: Contour plot of weight function Figure 9: 3D graphic of weight function As can be seen from the graphs above, as the characteristic year increases, the weight decreases linearly. And with the gap between two characteristic years increase, the weight increases somehow similar to a normal distribution curve.

4.4.2. The final cross-reference matrix

The weighted cross-reference matrix is defined as the original cross-reference matrix multiplied by the function value of weight function, via:

mo.crotha.m

e

(ti tj)22 2

)

) i,j 1,2, ,n (10)

帮助准备美赛同学作参考

Wij Zij WF(ti,tj)

Normalizing the weighted cross-reference matrix by column sums, we obtain the final

cross-reference matrix N.

Nij

Wij

n

(11)

ij

W

k 1

4.5. The Evaluation Vector

So far we have obtained the individual influence vector and the cross-reference matrix. Each of them partly reflect the impact that a certain coach has over the course of sports history. Furthermore, if one is related to a very influential coach, then this relationship can be more valuable to him. This law is far better than merely counting the correlated search results. Following this law, we sophistically combine the Article Influence Algorithm[19] with our data.

百度搜索“77cn”或“免费范文网”即可找到本站免费阅读全部范文。收藏本站方便下次阅读,免费范文网,提供经典小说医药卫生2014年美国大学生数学建模比赛获奖论文-F奖(8)在线全文阅读。

2014年美国大学生数学建模比赛获奖论文-F奖(8).doc 将本文的Word文档下载到电脑,方便复制、编辑、收藏和打印 下载失败或者文档不完整,请联系客服人员解决!
本文链接:https://www.77cn.com.cn/wenku/yiyao/1252708.html(转载请注明文章来源)
Copyright © 2008-2022 免费范文网 版权所有
声明 :本网站尊重并保护知识产权,根据《信息网络传播权保护条例》,如果我们转载的作品侵犯了您的权利,请在一个月内通知我们,我们会及时删除。
客服QQ: 邮箱:tiandhx2@hotmail.com
苏ICP备16052595号-18
× 注册会员免费下载(下载后可以自由复制和排版)
注册会员下载
全站内容免费自由复制
注册会员下载
全站内容免费自由复制
注:下载文档有可能“只有目录或者内容不全”等情况,请下载之前注意辨别,如果您已付费且无法下载或内容有问题,请联系我们协助你处理。
微信: QQ: