Chapter 03
小说连载：Pride And prejudice 傲慢与偏见 CHAPTER 03
NOT all that Mrs. Bennet, however, with the assistance of her five daughters, could ask on the subject was sufficient to draw from her husband any satisfactory description of Mr. Bingley. They attacked him in various ways; with barefaced questions, ingenious suppositions, and distant surmises; but he eluded the skill of them all; and they were at last obliged to accept the second-hand intelligence of their neighbour Lady Lucas. Her report was highly favourable. Sir William had been delighted with him. He was quite young, wonderfully handsome, extremely agreeable, and, to crown the whole, he meant to be at the next assembly with a large party. Nothing could be more delightful! To be fond of dancing was a certain step towards falling in love; and very lively hopes of Mr. Bingley's heart were entertained."If I can but see one of my daughters happily settled at Netherfield," said Mrs. Bennet to her husband, "and all the others equally well married, I shall have nothing to wish for."In a few days Mr. Bingley returned Mr. Bennet's visit, and sat about ten minutes with him in his library. He had entertained hopes of being admitted to a sight of the young ladies, of whose beauty he had heard much; but he saw only the father. The ladies were somewhat more fortunate, for they had the advantage of ascertaining, from an upper window, that he wore a blue coat and rode a black horse.An invitation to dinner was soon afterwards dispatched; and already had Mrs. Bennet planned the courses that were to do credit to her housekeeping, when an answer arrived which deferred it all. Mr. Bingley was obliged to be in town the following day, and consequently unable to accept the honour of their invitation, &c. Mrs. Bennet was quite disconcerted. She could not imagine what business he could have in town so soon after his arrival in Hertfordshire; and she began to fear that he might be always flying about from one place to another, and never settled at Netherfield as he ought to be. Lady Lucas quietedher fears a little by starting the idea of his being gone to London only to get a large party for the ball; and a report soon followed that Mr. Bingley was to bring twelve ladies and seven gentlemen with him to the assembly. The girls grieved over such a large number of ladies; but were comforted the day before the ball by hearing that, instead of twelve, he had brought only six with him from London, his five sisters and a cousin. And when the party entered the assembly room, it consisted of only five altogether; Mr. Bingley, his two sisters, the husband of the oldest, and another young man.Mr. Bingley was good looking and gentlemanlike; he had a pleasant countenance, and easy, unaffected manners. His brother-in-law, Mr. Hurst, merely looked the gentleman; but his friend Mr. Darcy soon drew the attention of the room by his fine, tall person, handsome features, noble mien; and the report which was in general circulation within five minutes after his entrance, of his having ten thousand a year. The gentlemen pronounced him to be a fine figure of a man, the ladies declared he was much handsomer than Mr. Bingley, and he was looked at with great admiration for about half the evening, till his manners gave a disgust which turned the tide of his popularity; for he was discovered to be proud, to be above his company, and above being pleased; and not all his large estate in Derbyshire could then save him from having a most forbidding, disagreeable countenance, and being unworthy to be compared with his friend.Mr. Bingley had soon made himself acquainted with all the principal people in the room; he was lively and unreserved, danced every dance, was angry that the ball closed so early, and talked of giving one himself at Netherfield. Such amiable qualities must speak for themselves. What a contrast between him and his friend! Mr. Darcy danced only once with Mrs. Hurst and once with Miss Bingley, declined being introduced to any other lady, and spent the rest of the evening in walking about the room, speaking occasionally to one of his ownparty. His character was decided. He was the proudest, most disagreeable man in the world, and every body hoped that he would never come there again. Amongst the most violent against him was Mrs. Bennet, whose dislike of his general behaviour was sharpened into particular resentment by his having slighted one of her daughters.Elizabeth Bennet had been obliged, by the scarcity of gentlemen, to sit down for two dances; and during part of that time, Mr. Darcy had been standing near enough for her to overhear a conversation between him and Mr. Bingley, who came from the dance for a few minutes to press his friend to join it."Come, Darcy," said he, "I must have you dance. I hate to see you standing about by yourself in this stupid manner. You had much better dance.""I certainly shall not. You know how I detest it, unless I am particularly acquainted with my partner. At such an assembly as this, it would be insupportable. Your sisters are engaged, and there is not another woman in the room whom it would not be a punishment to me to stand up with.""I would not be so fastidious as you are," cried Bingley, "for a kingdom! Upon my honour I never met with so many pleasant girls in my life, as I have this evening; and there are several of them, you see, uncommonly pretty.""You are dancing with the only handsome girl in the room," said Mr. Darcy, looking at the eldest Miss Bennet."Oh! she is the most beautiful creature I ever beheld! But there is one of her sisters sitting down just behind you, who is very pretty, and I dare say very agreeable. Do let me ask my partner to introduce you.""Which do you mean?" and turning round, he looked for a moment at Elizabeth, till catching her eye, he withdrew his own and coldly said, "She is tolerable; but not handsome enough to tempt me; and I am in no humour at present to give consequence to young ladies who are slighted by other men. You had better return to your partner and enjoy her smiles, for you are wasting your time with me."Mr. Bingley followed his advice. Mr. Darcy walked off; and Elizabeth remained with no very cordial feelings towards him. She told the story however with great spirit among her friends; for she had a lively, playful disposition, which delighted in any thing ridiculous.The evening altogether passed off pleasantly to the whole family. Mrs. Bennet had seen her eldest daughter much admired by the Netherfield party. Mr. Bingley had danced with her twice, and she had been distinguished by his sisters. Jane was as much gratified by this as her mother could be, though in a quieter way. Elizabeth felt Jane's pleasure. Mary had heard herself mentioned to Miss Bingley as the most accomplished girl in the neighbourhood; and Catherine and Lydia had been fortunate enough to be never without partners, which was all that they had yet learnt to care for at a ball. They returned therefore, in good spirits to Longbourn, the village where they lived, and of which they were the principal inhabitants. They found Mr. Bennet still up. With a book, he was regardless of time; and on the present occasion he had a good deal of curiosity as to the event of an evening which had raised such splendid expectations. He had rather hoped that all his wife's views on the stranger would be disappointed; but he soon found that he had a very different story to hear."Oh! my dear Mr. Bennet," as she entered the room, "we have had a most delightful evening, a most excellent ball. I wish you had been there. Jane was so admired, nothing could be like it. Every body saidhow well she looked; and Mr. Bingley thought her quite beautiful, and danced with her twice. Only think of that my dear; he actually danced with her twice; and she was the only creature in the room that he asked a second time. First of all, he asked Miss Lucas. I was so vexed to see him stand up with her; but, however, he did not admire her at all: indeed, nobody can, you know; and he seemed quite struck with Jane as she was going down the dance. So, he enquired who she was, and got introduced, and asked her for the two next. Then, the two third he danced with Miss King, and the two fourth with Maria Lucas, and the two fifth with Jane again, and the two sixth with Lizzy, and the Boulanger --""If he had had any compassion for me," cried her husband impatiently, "he would not have danced half so much! For God's sake, say no more of his partners. Oh! that he had sprained his ancle in the first dance!""Oh! my dear," continued Mrs. Bennet, "I am quite delighted with him. He is so excessively handsome! and his sisters are charming women. I never in my life saw any thing more elegant than their dresses. I dare say the lace upon Mrs. Hurst's gown --"Here she was interrupted again. Mr. Bennet protested against any description of finery. She was therefore obliged to seek another branch of the subject, and related, with much bitterness of spirit and some exaggeration, the shocking rudeness of Mr. Darcy."But I can assure you," she added, "that Lizzy does not lose much by not suiting his fancy; for he is a most disagreeable, horrid man, not at all worth pleasing. So high and so conceited that there was no enduring him! He walked here, and he walked there, fancying himself so very great! Not handsome enough to dance with! I wish you had been there, my dear, to have given him one of your set downs. I quite detest the man."中文翻译尽管班纳特太太有了五个女儿帮腔，向她丈夫问起彬格莱先生这样那样，可是丈夫的回答总不能叫她满意。
Chapter 3 Descriptive statistics(Numerical methods)
Chapter 3 Descriptirth noticing (1) Weight（权数）: The number to measure the importance (weights) of variables→ “f or f/∑f” ∑ [Example] During the “Oct. 1st”, 10 students go to different tourist site: Mt. Huang→5 persons, Mt. Wuyi→2 , Mt. Tai→2 , Mt. Laofu→1.
Total age 15 + 16 + 16 + L + 18 170 x= = = = 17 Number of persons 1+1+1+L+1 10
x1 + x 2 + x 3 + L + x n Σx ∴x = = = E ( x) 1+1+1+L+1 n Σx （1）Simple arithmentic mean：x = n
Difficulties
1. Mean； Mean； 2. Variance and standard deviation。 deviation。
Chapter 3 Descriptive statistics
STAT
Section 1 Central tendency and tendency of dispersion 1. Concepts tendency（集中趋势） 1） Central tendency（集中趋势）: The closer to middle the variable gets, the larger the frequency is. The reverse is also true. 2） Tendency of dispersion（离中趋势）: The tendency of dispersion（离中趋势） deviating and dispersed at the two ends.
Chapter03_PPT
13
3.2 Simple Program: Printing a Line of Text
Up arrow
Down arrow Parameter List window
Parameter Info window
Fig. 3.6
Parameter Info and Parameter List windows.
Chapter 3 – Introduction to Visual Basic Programming
Outline 3.1 3.2 3.3 3.4 3.5 3.6 3.7
1
Introduction Simple Program: Printing a Line of Text Another Simple Program: Adding Integers Memory Concepts Arithmetic Decision Making: Equality and Relational Operators Using a Dialog to Display a Message
2002 Prentice Hall. All rights reserved.
7
3.2 Simple Program: Printing a Line of Text
Left pane Right pane
Project name
File locationnsole Application with the New Project dialog.
2002 Prentice Hall. All rights reserved.
8
3.2 Simple Program: Printing a Line of Text
宏观经济学---曼昆chap03
National Income
Marginal product of labor (MPL )
definition: The extra output the firm can produce using an additional unit of labor (holding other inputs fixed): MPL = F (K, L +1) – F (K, L)
CHAPTER 3
National Income
Exercise: Compute & graph MPL
a. Determine MPL at each value of L.
b. Graph the production function. c. Graph the MPL curve with MPL on the vertical axis and L on the horizontal axis. L 0 1 2 3 4 5 6 7 8 9 10 Y 0 10 19 27 34 40 45 49 52 54 55 MPL n.a. ? ? 8 ? ? ? ? ? ? ?
Labor (L)
Labor (L)
CHAPTER 3
National Income
MPL and the production function
Y
output
MPL
As more labor is added, MPL
F (K , L)
1
MPL
1
MPL
1
Slope of the production function equals MPL
CHAPTER 3
CHAP03
6
Figure 3-2 -- Basic E-R Notation A special entity that is also a relationship
Entity symbols
Attribute symbols Relationship symbols
Chapter 3
Prentice Hall, 2002
– Simple versus Composite Attribute – Single-Valued versus Multivalued Attribute – Stored versus Derived Attributes – Identifier Attributes
Chapter 3
10
lines between entity types…the instance is between specific entity instances
Relationships can have attributes
– These describe features pertaining to the association between the
7
What Should an Entity Be?
SHOULD BE:
– An object that will have many instances in the
database – An object that will be composed of multiple attributes – An object that we are trying to model
15
Figure 3-8 -- Entity with a multivalued attribute (Skill) and derived attribute (Years_Employed) What's wrong with this?
chapter-03
Nebula M1-67 around star WR124
小结
不同初始质量恒星的演化结局
3. 超新星 (Supernovae) 和超新星遗迹 (Supernova Remnants) II/Ib/Ic型超新星—高质量恒星在演化末态发生的 剧烈爆炸。
星系M 51中的SN 1991T
特征：
光度L～107-1010 L⊙， Lf /Li ～ 108 爆发能E～1047-1052 ergs（其 中 中 微 子占 99% ，动 能占 1% ，可见光辐射占0.01%） 膨胀速度v～103-104 kms-1
不同质量主序星的演化时标
M (M⊙) tn (yr) 30 2×106 15 107 1.0 1010 0.5 6×1010
主序星的内部化学 组成的变化
随着核反应的进行，核 心区的H元素丰度逐渐 减小，直至枯竭，全部 转变成He。
演化路径 (Evolutionary Track)
核反应4 H → 4He →核心区粒子数n↓→Pc↓ → 核心收缩R c↓ R → 核心区温度Tc↑，核反应 产能率ε↑ → 光度L↑ → 包层压力P↑ → 恒星半径R↑ 主序带：主序星从核心H 燃烧开始到结束在H-R图 上占据的带状区域
(2) 热时标 (thermal timescale) 恒星辐射自身热能的时间，或光子从恒星内部到 达表面的时间。 tth ＝ (0.5GM2/R)/L ≈ (2×107 yr) (M/M⊙)2 (R/R⊙)−1 (L/L⊙)−1 (3) 动力学时标 (dynamical timescale) 如果恒星的内部压力突然消失，在引力作用下恒 星坍缩的时间。 td ＝ R/V ≈ (R3/GM)1/2 ≈ (27 min) (R/R⊙)3/2(M/M⊙)−1/2
Chapter03-Application Software
Next
Business Software
What is business software?
Application software that assists people in becoming more effective and efficient
p. 138 Fig. 3-4
Next
Business Software
Next
Business Software
What are popular word processing features?
AutoCorrect Columns AutoFormat Collaboration Macros
Grammar Checker Reading Layout Tables
Next
Business Software
What is note taking software?
Enables users to enter typed text, handwritten comments, drawings, or sketches anywhere on the page Notes are organized like a notebook
p. 135 Fig. 3-2
Next
Application Software
How do you start an application?
From the desktop, click the Start button, point to All Programs, and click the name of the application The program’s instructions load into memory
Chapter 03_SA&GP
3.1 How to Convert an LP to Standard Form
Before the simplex algorithm can be used to solve an LP, the LP must be converted into a problem where all the constraints are equality equations and all variables are nonnegative. An LP in this form is said to be in standard form.
15
3.4 Why Does LP Have an Optimal bfs?
Theorem 3 If an LP has an optimal solution, then it has an optimal bfs. Proof: Omitted.
For any LP with m constraints, two basic feasible solutions are said to be adjacent if their sets of basic variables have m – 1 basic variables in common.
7
3.2 Preview of the Simplex Algorithm
Consider a system Ax = b of m linear independent equations in n variables (where n ≥ m). A basic solution to Ax = b is obtained by setting n–m variables equal to 0 (But setting which variables?) & solving for the remaining m variables. By setting the n–m variables equal to 0, which yields a unique value for the remaining m variables.
文体学 Chapter 03
Tense That will be John. That was John. It is raining and I have nothing to do, so I suppose I might as well write.
It was raining and he or she had nothing to do.
• (rules for the) arrangement of words into phrases and phrases into sentences • Syntax refers to the rules for ordering and connecting words into sentences. What is the right way of arranging the elements in a sentence.
III. Sentence Types simple sentence
compound
multiple sentence complex
complex compound
Major : conforming to the regular patterns
SPOCA • consisting of a dependent clause • non-finite construction • phrase • elliptical sentence • abbreviated sentence • block language
(how) (what)
situation type dynamic
sub-type action
verb type agentive
participant roles
chapter03part01recommendation推荐系统.ppt
Recommender Systems
How do you know you can trust somebody’s recommendation?
Because experience has taught you? Because critic is trusted source of info? Because a friend/expert likes movies/novels/
Problems Cold-start: at initial stage, users can not get good recommendations Scalability Sparsity Users with different opinion or unusual taste may not get good recommendations
food you like? ???
Applications:
Book Recommender
Red Mars
Found ation
Jurassic Park
Lost World
2001
Difference Engine
Machine Lea User-Based
high correlation
like
A
B
C
Use user-item preferences
Explicit user ratings, transaction data
1. Find highly correlated users
Pearson correlation between user rating data
ru, j wa,u Pa, j uU wa,u ,
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Reduced Costs 0.00000 0.00000 Dual Prices 4.37496 0.00000 6.93753 0.00000
Ling Xueling
第三节 L.P. 计算机解法
Objective Coefficient Ranges
Variable Lower Limit x1 6.30000 x2 6.66670 Right Hand Side Ranges Constraint Lower Limit 1 495.59998 2 479.99930 3 580.00146 4 117.00012 Current Value 10.00000 9.00000 Current Value 630.00000 600.00000 708.000000 135.00000 Upper 13.49993 14.28572 Upper 682.36316 No Limit 900 No Limit
2,松弛/剩余和对偶价格
界限约束 slack = 0 非界限约束 slack ≠ 0 改善值,所以有松弛的约束式对偶价格 = 0 因为对偶价格是改善 改善
3,敏感性分析
1〕c j 保优区域(Objective Coefficient Ranges)--使最优解有效的 区间,c1 = 10 ∈[6.3, 13.5] 2〕b i 可行区间( Right Hand Side Ranges )--使对偶价格有效的 区间,b1 = 630 ∈ [495.6, 682.4]
1) 现实世界是动态变化 动态变化的,所有系数都会变化,如:市场变化,售价 动态变化 的变化将导致利润率的变化,进而导致目标函数之系数的变化 2)有些数据是可控 可控的,如:是否加班?将导致可用工时的变化 可控 3)不少模型中的数据本来就是估计的,近似 近似的 近似
对修正了的 L.P. 模型不再重新求解,也要有足够的信息回答 上述变化所带来的影响--对最优解的影响,即:动态变化 或近似估计允许的范围是什么?
Ling Xueling
第三节 L.P. 计算机解法
1,最优解和缩减成本(reduced costs)
对于每一个决策变量 xj ,为使其在最优解中取得正数,其对应的 o.f. 之系数 cj 所必须改变的值的大小 此例中,x1 = 540 > 0,x2 = 252 > 0, 故,对应缩减成本均为 0
Ling Xueling
第三节 L.P. 计算机解法
二,MS 实例求解
2,软件启动
开始 \ 程序 \ MS60 Select A Module 菜单操作即可 注意: 1)非负约束 不要输入 2) "≤"约 束只要输入"<".
Ling Xueling
第三节 L.P. 计算机解法
三,计算机输出信息的解释 Objective Function Value = 7667.99463 Variable Value x1 539.99841 x2 252.00113
Ling Xueling
第一节 敏感性分析介绍
二,实例--Par. 公司问题
1,原问题及最优解
Max 10 x1 + 9 x2 s.t. 7/10 x1 + x2 ≤ 1/2 x1 + 5/6 x2 ≤ x1 + 2/3 x2 ≤ 1/10 x1 + 1/4 x2 ≤ x1, x2 ≥ 0
Ling Xueling
≤ 1 =目标函数直线斜率≤ 2 c2 10
故,cj 的保优区域是:
令
c2 = 9 c1 = 10
6.3 ≤ c1 ≤ 13.5 6.67 ≤ c2 ≤ 14.29 ( 暂时不讨论联立 联立变化) 联立
Ling Xueling
第二节 敏感性分析图解法
一,关于 cj 的变化
3,特殊情况时 C1 的保优区域
n
∑a x
j =1 ij
j
≤ bi
(i =1 2,...., m) ,
xj ≥ 0 ( j =1 2,...., n) ,
Ling Xueling
第一节 敏感性分析介绍
一,概念
2,什么是敏感性分析 最优后分析.就是在 L.P. 求出最优解之后,要研究: 最优后分析 1)当 c j 发生变化时,对最优解 x j 的影响是什么? 解 2)当 b i 发生变化时,对最优解值 z = o.f. 的影响是什么? 解值 3,为什么要进行敏感性分析?
二,关于右手边值 b i (资源)的变化
问题:1)可行域变化?---- 一般要变 2)最优解变化?---- 一般要变 3)最优解值 3 解值增量的意义是什么? 解值
1,实例
在 Par. 公司问题的第一个约束式中令 b1 = 640 则因为可行域增大,最优解变成:x1 = 527.5, x2 = 270.75 o.f. = 7711.75 即:利润增加 7711.75 - 7668 = 43.75 = z 也即:4.375 / 工时 (对 C&D 工序来说).
3,bi 变化与最优解值 z 值
1)bi 变化时,z 如何变化? 2)bi 增加时,附加工时的价值 (z2-z1) 是什么?
Ling Xueling
第一节 敏感性分析介绍
3 of 四约束之截距分别是: (900,630) (1200,700) (708,1062)(1350,540) 约束一直线之斜率= - 7/10 1 约束三直线之斜率= - 3/2
Ling Xueling
两个以上决策变量的 L.P. 问题例子
数学模型
max z = max 90x1 + 84x2 + 70x3 + 60x4 s.t. 10x1 + 8x2 + 9x3 + 15x4 ≤ 5000 2x1 + 3x2 + 3x3 ≤ 1800 x1 + x2 + x3 + x4 = 600 x3 x1 , x2 , x3 , x4 ≥ 0
∑b 最大允许量-b原始值
i i
20 100 + = 90.27% <100% 得联立变化百分比是: 682.4 630 900 708
故, b1 / b3 的对偶价格仍然皆有效.
Ling Xueling两Biblioteka 以上决策变量的 L.P. 问题例子
销售双工无线电联络系统问题 1,目标:利润最大 2,条件和约束
四种渠道:专业批发商 / 一般批发商 / 零售 / 邮购 不同渠道时:不同利润 / 不同广告成本 / 不同售后服务时间 资源和有关数据: 单位广告预算 10,8,9,15,可用总量:5000 单位服务时间 2,3,3,0,总可用时间:1800 已安排生产 600 第三渠道已签约 150 利润率 90 / 84 / 70 / 60 (课堂练习建立模型).
洛伦兹效应
1963 年气象学家洛伦兹提出著名的"蝴蝶效应 "假说 假说:一只南美洲亚马孙河流域热带雨林中 假说 的蝴蝶,偶尔扇动几下翅膀,可能在两周后引 起美国得克萨斯的一场龙卷风 原因在于:蝴蝶翅膀的运动,导致其身边 身边的空 身边 气系统发生了变化,并引起微弱气流的产生, 而微弱气流的产生又会引起它四周 四周空气或其他 四周 系统产生相应的变化,由此引起连锁反应,最 终导致其他系统 系统的极大变化. 系统
Ling Xueling
第三章 线性规划敏感性分析 和计算机解法
敏感性分析: 除最优解外,为决策者提供有价值的额外 额外信息 额外 计算机求解: 解决具有两个以上变量的 L.P. 问题
Ling Xueling
第一节 敏感性分析介绍
一,概念 1,L.P. 一般式
n
m ∑cj xj ax
j= 1
s.t.
Ling Xueling
洛伦兹效应
洛伦兹效应的解释:事物发展的结果,对初 初 始条件具有极为敏感的依赖性,初始条件的 始条件 极小偏差,可能引起结果的极大差异 "蝴蝶效应" 在社会学界常常被用来说明: 一个坏的微小的机制,如果不加以及时的引 导,调节,很可能会给社会带来非常大的危 害,被戏称为 "龙卷风" 或 "风暴";一个 好的微小的机制,只要正确指引,经过一段 时间的努力,将会产生轰动效应,被称为 " 革命"
630 600 708 135
最优解 x1 = 540 x2 = 252
第一节 敏感性分析介绍
二,实例
2,cj 变化与最优解 xj
1)若 c1 = 10 变成 7,问:最优解变化吗? 2)若 c2 在 (5, 13) 变化时最优解不变,如何评价 c2 = 9 ? 3)若仅当 c2 ∈ (8.9, 9.25) 时最优解不变,超出这个范围哪怕 一点点,最优解就会变,又如何评价 c2 = 9 ?
改令 则新最优解是 令 c2 = 9 从 从 z = 18 x1 + 9 x2 x1 = 708 x2 = 0
c1 3 ≤ c2 2
得下界 得上界
c1 ≥ 13.5 c1 < +
c1 > ∞ c2
∞
Ling Xueling
即得 C 1 保优区域:
13.5 ≤ C1 < +
∞
第二节 敏感性分析图解法
Ling Xueling
第二节 敏感性分析图解法
二,关于右手边值 b i (资源)的变化
4,b i 允许变化的区间
1)对偶价格定义(dual price) b i 每增加 增加一个单位时,o.f. 的改善 改善值 增加 改善 显然,在 max 问题中,dual = shadow 在 min 问题中,dual = - shadow 2)b i 可行区间(range of feasibility)定义 使得对偶价格有效的区间称为 b i 的可行 可行区间 使得对偶价格有效的区间 可行 意义:可行 ---- 就是要保证"对偶"有效,即:资源配置的 增,减幅度应该控制在有效,可行范围内 问题:如何求 b i 的可行区间?--下面一节解决.