lecture7(process,cause-effect,example)

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Cause and Effect Essay因果的一些说明 精选文档

Cause and Effect Essay因果的一些说明 精选文档
? Sufficient Cause - one that can produce an effect unaided, though there may be more than one sufficient cause of a given effect.
? Ex. A dead battery is enough to keep a car from starting--but faulty spark plugs (火花塞故障) or an empty gas tank will have the same effect.
? Did I distinguish between primary (most important) and secondary (ancillary) effects?
Writing the Cause and Effect Essay
? Read through the hand-outs on how to organize and write a cause and effect essay.
? Contributory Cause - one that helps to produce an effect but cannot do so by itself.
? Ex. Running a red light might help to cause an accident....though other facts -- pedestrians or other cars in the intersection -- must also be present.
Kinds of Causal Relations
? Necessary Cause - one that must be present for the effect to occur.

lecture7模型设定(1)

lecture7模型设定(1)
• There is no accepted “best” way of going about finding a correct specification, 但有一些经验。
1 Scaling Effect and Beta Coefficients
• 两个问题: – Statistically significant, but very small coefficient has any meaning?
population
2 Functional Form: log
• Log-dependent
– semi-elasticity (percentage change) • Sales increase over time, affected by • but approximate error is large when the coefficient is large
0 Introduction
• 因为没有true model,模型的设定就变得非常重要 –它甚至比模型的估计与检验来得更重要 –但很不幸,我们这门功课主要讲估计和检验.而模型 的设定是经济学、金融学等的任务。
• 那能否通过数据来设定模型? – Data can never speak for themselves. Fact can never speak for themselves –模型是窗口,窗口放在哪里是人定的。当然我们还是 希望能“窗口”能客观全面一些
– Variables being large integer values, the log is often taken: population, total number of employees, and school enrollment

Lecture-7-商务信函的翻译(翻转课件)

Lecture-7-商务信函的翻译(翻转课件)
第8页,共30页。
2. 英语商务信函的文体特点
2.1.词汇特点:(2)表意准确,专业性强
• 主要表现在使用大量的专业术语、行话、外来词、缩略语以 及一般词语在商务英语语境中的特殊用法
• We shall cover TPND on your order. 我们将为你方的货物投保盗窃和提货不着险。
• It would be appreciated if you would let us know by returning your lowest possible price for the following goods on FOB London.
Chapter Three
商务信函的翻译
第1页,共30页。
Business Letters
知识目标: 1. 了解商务信函的行文方式、格式和文体特点。 2. 掌握商务信函的常用翻译技巧。
能力目标: 1. 能够正确翻译商务信函常用词汇和句型。
2. 能够熟练地翻译各类商务信函。
第2页,共30页。
商务信函(business letters) 商务信函涉及商务活动的各个环节,贯
称呼(Salutation)
事由/标题(Subject or Caption) Subject: Invoice No. 201 BY05 正文(Body of the Letter) 结束语(Complimentary Close) 签名(Signature) (签字,打印 ,职务) 姓名首字母(Initials) (发信人及打字员 ) SW/JM 附件(Enclosure),Encl.: sample 抄送/副本(Carbon Copy),C.C.: General Manager 附言(Postscript),P.S.:

2011年秋lecture7-学生翻译作业-含参考译文 (1)

2011年秋lecture7-学生翻译作业-含参考译文 (1)
to talk to you about… Good morning, everyone. I am very happy to have this chance to give my presentation. I am very happy/glad/pleased to be here.
2). Introducing the Subject and the outline of the Presentation引入话题 a. Background Information
Let us start with…
II. Presentation English
1. Beginning the Speech
1). Opening Remarks 开场 Good morning, everyone. I appreciate the
opportunity to be with you today. I am here
Lecture 7 Translation Assignments and Presentation English
I. 翻译作业
Scientists are confident that all matter is indestructible(不可毁灭的). Many chemical reactions need heat to make them take place. Machine parts of irregular shape can be washed very clean by ultrasonic. The expression of the relation between force, mass and acceleration is as follows.

lecture7-设计模式小结及实例

lecture7-设计模式小结及实例

内容提要★结构型设计模式小结包装型模式群设计模式实例分析Structural Patterns结构模式描述如何将类或者对象结合在一起形成更大的结构。

类的结构模式:类的结构模式使用继承把类、接口等组合在一起,以形成更大的结构。

当一个类从父类继承并实现某接口时,这个新的类就把父类的结构和接口的结构组合起来。

类的结构模式是静态的。

对象的结构模式:对象的结构模式描述了怎样把各种不同类型的对象组合在一起,以实现新功能的方法。

可以在运行时刻改变对象组合关系,对象的结构模式是动态的。

结构模式主要有:Adapter 适配器模式Bridge 桥接模式Composite组合模式Decorator 装饰模式Facade 门面模式Flyweight享元模式Proxy 代理模式1 AdapterAliases:WrapperIntent将一个类的接口转换成客户希望的另外一个接口。

Adapter模式使得原本由于接口不兼容而不能一起工作的那些类可以一起工作Motivation有时为复用而设计的工具箱类不能够被复用的原因仅仅是因为它的接口与专业应用领域所需要的接口不匹配图示:1. 对象Adapter:Adapter与Adaptee是委派关系图示:2. 类Adapter:Adapter与Adaptee是继承关系Adapter 模式的关键特征Adapter 模式的关键特征用一个满足现有接口需求的新类包含已有类,调用已有类的方法实现新类中的方法实现Adapter 模式使得先前存在的对象可以匹配新的类型,而不受该对象原有接口的限制效果Adapter 对Adaptee 进行适配,使其满足Adapter’s Target 的要求。

这是的用户可以实际使用Adaptee ,就好像它是一种Target 一样。

参与者和协作者Adapter 面向所需的接口提供一个包装器解某系统拥有合适的数据和行为,但接口并不合要求。

问题将一个你难以控制(如无法修改其内部代码)的对象匹配到特定的接口上意图2 BridgeAliases:Handle/BodyIntent将抽象部分与它的实现部分分离,使它们都可以独立地变化Motivation要做到“抽象(接口)与实现分离”,最常用的办法是定义一个抽象类,然后在子类中提供实现。

Lecture-7-How-to-Write-a-ConclusionPPT课件全文

Lecture-7-How-to-Write-a-ConclusionPPT课件全文

.
6
The Conclusion
Remind your reader why you have been writing this essay!
It’s been a long while since your Topic Sentence!
So, rephrase your Topic Sentence.
this paper I have explained...")
.
9
Sample Conclusion:
Macbeth started off as a hero and ended up a hated tyrant. Such power-hungry people are still around today and continue to cause great instability in society. That is why we continue to have political unrest and wars and we hear about them daily in the news. Sadly, Shakespeare has shown us that selfish, naked ambition is one of humanity’s timeless vices.
If your introduction went from general to specific, make your conclusion go from specific to general.
Think globally.
.
13
Suggestions
4. Echoing the introduction: Echoing your introduction can be a good

Lecture7 Producer theory

Lecture7 Producer theory

Producer Theory1Technology1.Production is a process of transforming inputs into outputs.Thefundamental problem…rms must contend with in this process is the technological feasibility.The state of technology determines and restricts what is possible in combining inputs to produce out-put.2.We…rst concentrate on the case in which the…rm produces onlyone output.The case of multiple outputs will be dealt with later.When there is only one output,we will use q2R+to denote the …rm’s output and x2R n+to denote the…rm’s inputs.3.We de…ne the production function as:q=f(x):The production function captures the technology of production.It tells us how much input x is needed to produce a a…xed amount of output q.4.Assumption3.1.The production f:R n+!R+,is continuous,strictly increasing,and strictly quasiconcave on R n+,and f(0)=0.5.The marginal product of x i,MP i=@f @x i;tell us how many extra units of output an extra unit of x i produces. Unlike marginal utility in consumer theory,marginal product is objective and measurable.6.The strict quasiconcavity assumption means that any convex com-bination of two input vectors can produce at least as much output as one of the original two.This would be the case if we have diminishing marginal product.7.For any…xed level of output q,the set of input vectors producingq is called q-level isoquant.This plays the same role as indi¤erence curve in consumer theory.An isoquant traces out all the combina-tions of inputs that allow that…rm to produce the same quantity of output.8.The substitutability between any pair of inputs x i and x j is themarginal rate of technical substitution(MRTS).MRTS measures the amount of one input i the…rm would require in exchange for using a little less of another input j in order to just be able to produce the same output as before.A q-level isoquant is de…ned as:f(x)=q:Given x ij,let x j(x i)be the amount of x j required to keep out-put constant.If we di¤erentiate the isoquant with respect to x i, holding x ij constant,we get@f @x j dx jdx i+@f@x i=0:Rearranging the terms gives the slopeMRT S ij(x)= dx jdx i=@f@x i@fj:Since f is strictly quasiconcave,MRTS is diminishing.9.Elasticity of substitution:for a production function q=f(K;L);the elasticity of substitution ;measures the proportionate change in K=L relative to the proportionate change in the MRTS along the isoquant.That is,=% KL% MRT S L;K=dK=LdMRT SMRT SK=L=d ln(K=L)d ln MRT S:The shape of the isoquants indicates the degree of substitutability.10.De…nition:we classify the returns to scale of a production function,f(K;L),as follows:E¤ect of Output(m>1)Returns to Scale f(mx)=mf(x)Constantf(mx)<mf(x)Decreasingf(mx)>mf(x)Increasing11.Constant returns to scale means if you multiply all inputs by factorm>1,the output is increased by factor m.Increasing returns to scale means if you multiply all inputs by a factor m,the out-put increases by a factor more than m.That is,you can get proportionally more as you expand.Decreasing returns to scale is just the opposite to increasing returns.A production function can have increasing returns over some range and decreasing returns over another.In fact,a lot of times there is some optimal scale in between:it is ine¢cient to be too small and ine¢cient to be too big.12.Locally,the elasticity of scale at point x is de…ned by(x) limm!1d ln[f(mx)]d ln(m)=P n i=1f i(x)x if(x):1.1Special production functions1.Linear production function:perfect substitutes2.Cobb-Douglas production functionsq=AL K ;where A; ; >0.3.Leontief production functionsq=min K; L :4.CES production functionq=A h L 1 +(1 )K 1 i 1where A>0; 2(0;1); >0. is the elasticity of substitution.(a) =+1,linear production function.(b) =1,Cobb-Douglas production function.(c) =0,Leontief production function.5.Homothetical production function:homothetical production pro-duces a linear expansion path starting from the origin,optimal input ratio at various output level is constant given…xed input prices.2Cost Minimization2.1Long-run Cost minimization1.Some cost de…nition(a)Opportunity cost:the value of a resource in its best alterna-tive use.(b)Sunk costs are those unrecoverable costs that have alreadybeen incurred and the resources have no alternative use.2.Short-run vs.long-run cost minimization(a)Long-run:free to vary quantities of all its inputs as much asit desires.(b)Short-run:unable to adjust the quantities of some of its in-puts.3.Long-run cost-minimization.Let w denote input prices.The costminimization problem is de…ned as:minxwxs:t:f(x) q:L=wx+ (q f(x)):The…rst-order conditions:@L@x i=w i f x i=0;i=1;:::;n@L@=q f(x)=0;From the…rst n equations,we get for all iw if xi= .4.Recall f xi is the extra output the…rm can make from one extraunit input i,so1x i is the amount of input i required to produceone unit of output,and wf xi is the cost for producing one extraunit of output using input i.A cost-minimizing…rm chooses an input combination such that the cost for producing one extra unit of output is the same no matter what input mixes the…rm choose to increase output.5.Example 1:Cobb-Douglas production functionq =50L 1=2K 1=2:MRT S L;K =K L =w r =)K (r;w )=w rL:Plugging K (r;w )into the production functionq =50L 1=2 w r L 1=2=)L =q 50 r w1=2:Similarly,K =q 50 w r 1=2:parative statics of change in output(a)The cost minimizing input combinations,as q 0varies,traceout the expansion path .(b)If the cost minimizing quantities of labor and capital rise asoutput rises,labor and capital are normal inputs .(c)If the cost minimizing quantity of an input decreases as the…rm produces more output,the input is called an inferior input .7.Properties of Cost FunctionIf f is continuous and strictly increasing,then the cost functionc (w;q ) min x wx s:t:f (x ) q is(a)Zero when q =0.(b)Continuous on its domain.(c)For all w >>0,strictly increasing and unbounded above inq .(d)Increasing in w:(e)Homogeneous of degree one in w:(f)Concave in w .(g)Shephard’s lemma:c (w;q )is di¤erentiable in w at (w 0;q 0)whenever w 0>>0;and @c (w 0;q 0)@w i=x i w 0;q 0 ;i =1;:::;n:2.2Conditional Input DemandsSuppose the production function satis…es Assumption 3.1and that the associated cost function is twice continuously di¤erentiable.Then1.x (w;q )is homogeneous of degree zero in w:2.The substitution matrix,0B B B @@x 1(w;q )@w 1@x 1(w;q )@w n::::@x n (w;q )@w 1@x n (w;q )@w n1C C C A is symmetric and negative semide…nite.In particular,the semidef-initeness property implies that for all i@x i (w;q )@w i0.2.3Short-run cost-minimization1.The …rm’s short-run cost minimization problem is to choose quan-tities of the variable inputs so as to minimize total costs,given that the …rm wants to produce an output level q and under the constraint that the quantities of the …xed factors do not change.min xwx + w x s:t:f (x; x ) q:2.Three inputs short-run cost-minimizationmin L;MwL +mM +r K s:t:q =f (L;K;M )Note:L;M are the variable inputs and wL +mM is the total variable cost. Kis the …xed input and r K is the total …xed cost.Tangency condition:MP L w =MP M m:Constraint:q =f (L;K;M ):3.Suppose that K is the long run cost minimizing level of capital foroutput level q .Then when the…rm produces q ,the short-run demands for L and M must yield the long-run cost minimizing levels of L and M4.Exampleq=K1=2L1=4M1=4;r=2;w=16;m=1: The short-run cost-minimization condition when q=16, K=32:(a)Short-run Tangency condition:MP L MP M =ML=wm=161=)M=16L:Constraint16=321=2L1=4(16L)1=4;which gives L=2,and M=16L=32.Thus when q= 16; K=32,the short-run cost minimization inputs combina-tion isL=2;M=32:(b)Long-run cost minimization when q=16:Two tangency conditionMP L MP M =ML=wm=161=)M=16L;MP L MP K =2KL=wr=162=)K=16LConstraint16=(16L)1=2L1=4(16L)1=4=)1634L=16=)L=1614=2: Plugging L=2into tangency conditionM=16L=32;K=16L=32:Hence when K=32is the long-run cost minimizing level of capital for the output level q=16,the short-run cost minimization yields the long-run cost minimizing levels of L and M.5.For the previous example,the long-run cost given input pricesr=1;w=16;m=1isc(q)=8q:The short-run cost…xing K=32issc(q; K)=64+q2 4 :Clearly sc(q; K) c(q)for all q 0:3Pro…t Maximization1.To…nd the optimal outputmaxf q gpq c(w;q) The…rst order condition implies thatp=@c@q(1)and the second order condition is that@2c@q2>0:By the…rst order conditions,we can get the…rm’s output supply function,q =q(p;w):2.To…nd the optimal inputsmaxf x gpf(x) wxUsing the…rst order condition we havep @f@x i=w i;for i=1;:::;n:The…rst-order conditions mean that the marginal revenue product (MRP)of each input i should equal the input price.MRP gives the rate at which revenue increases per additional unit of input i employed.The…rst-order conditions will give us the input demand function of the…rm,x =x(p;w):3.Theorem3.7.If f satis…es Assumption3.1,then for p 0andw 0;the pro…t function(p;w) max pq c(w;q)when well-de…ned,is continuous and(a)Increasing in p:(b)Decreasing in w:(c)Homogeneous of degree one in(p;w):(d)Convex in(p;w):(e)Di¤erentiable in(p;w)>>0.Moreover,(Hotelling’s lemma),@@p=q;@ @wi=x i:4.Theorem3.8.Suppose is well-de…ned and twice continuouslydi¤erentiable,then(a)q and x i are homogeneity of degree zero.(b)The substitution matrix0B B B B B @@q@p@q@w1:::@q@w n@x1(p;w)@p @x1(p;w)@w1::: @x1(p;w)@w n ::::::::::::@x n(p;w)@p @x n(p;w)@w1::: @x n(p;w)@w n1CC C C CAis symmetric and positive semide…nite.In particular,@q 0and@x i(p;w)@w i 0for all i.5.Example:Price P,input prices(w1;w2)q=x 1x 2where ; >0.The…rst order condition givesP x 11x 2 w1=0;(2)P x 1x 12 w2=0;(3)q x 1x 2=0:(4) The…rst two conditions imply that x2= x2=w1=w2and thus, x2=( w1= w2)x1.Plugging it back into(4)yieldsx1=q1 + w2 w1 + ;x2=q1 + w1 w2 + :Plugging the two conditional input demands into (2)gives P q + 1+ w 2w 1 + =w 1=)q+ 1 + =P 1w + 1w + 2 + + =)q =P +1 w + 11w + 12 1 1 ;x 1(P;w )=P 11 w 1 ( + 1)1w ( + 1)2 1 (1 ) 1 ;x 2(P;w )=P 11 w ( + 1)1w 1 ( + 1)2 (1 ) 1 1 :Plugging q (P;w )back into the conditional input demand gives x i (P;w ).And the pro…t function(P;w )=P q (P;w ) wx (P;w ):Note that when + <1,dq (P;w )dP >0@x i (P;w )@w i<0:6.When + =1or + >1;q (P;w )and x i (P;w )are unde…ned,therefore,the pro…t function is not de…ned.To show this,the pro…t function de…ned as before:(p;w ) max pf (x ) wx:Suppose that x 0and f (x 0)maximize pro…ts at p and w:With in-creasing returns,f (tx 0)>tf (x 0)for all t >1:Thus,pf (tx 0) wtx 0>tf (x 0) wtx 0 f (x 0) wx 0for all t >1:This says higher pro…t can always be had by increasing inputs in proportion t >1;which contradicts our assumption that x 0and f (x 0)maximized pro…t.7.Note that in the special case of constant returns,no such problem arises if the maximal level of pro…t happens to be 0.In that case,though,the scale of the …rm’s operation is indeterminate because (f (x 0);x 0)and (tf (x 0);tx 0)give the same level of 0pro…ts for all t >0:4Multiple outputs1.Another way to represent the technology constraint is to think ofthe…rm as having a production possibility set,Y R n;where each vector y=(y1;y2;:::y n)2Y is a production plan,where y i>0means outputs and y j<0means inputs.2.A production plan y2Y is technological e¢cient if there isno b y2Y such that b y>y:A production plan is economically e¢cient if it maximizes pro…ts =py of a given price vector p:3.Economic e¢ciency implies technological e¢ciency.No matterwhat the prices of inputs and outputs are,the…rm needs to achieve technological e¢ciency in order to achieve pro…t maximization.We can think of the…rm’s choice problem in two steps:…rst,the…rm has to achieve technological e¢ciency;second,the…rm obtain eco-nomic e¢ciency on the e¢cient production set or the production possibility frontier(PPF).The PPF is de…ned to be the set of all technologically e¢cient production plans.4.Formally,given a production plan y=(y1;y2;:::y n)2Y;thereis a twice di¤erentiable function G:R n!R that de…nes the production possibility set:Y f y2R n j G(y) 0g:5.Assumption1.Strict Monotonicity.That is,G yi >0;8i;y:By thisassumption,since G yi >0,any y such that G(y)<0is technolog-ically ine¢cient:one can increase the production(or decrease theuse)of one product y i while keeping others constant(some y i areinputs).Therefore,f y2R n j G(y)=0g is the technologically e¢-cient production set and is thus called the production possibilityfrontier(PPF).6.We de…ne the marginal rate of transformation(MRT)asMRT ij @y i@yj =G yjG yi>0:MRT is the slope the PPF.7.Assumption2.G is quasi-convex.The…rm’s problem is then:(p) maxy2R npys:t:G(y) 0:Since technological e¢ciency is necessary for economic e¢ciency (pro…t maximization),the above problem is equivalent to(p) maxpyy2R n s:t:G(y)=0:。

英文写作-Lecture-14-Cause-and-Effect

英文写作-Lecture-14-Cause-and-Effect

Three Designs of Cause-effect Essay
One is to ascertain causes; The other is to consider effects; Still others discuss both causes and effects.
Ascertaining Causes
Thesis: Our out-of-control anger has understandable causes , but common sense and patience are more satisfying than outbursts of rage. To begin with, American work longer hours and are rewarded with less vacation time.
Introduction
Supporting Point 1(Cause 1) Supporting Point 2(Cause 2) Supporting Point 3 (Cause 3)
Paragraphs1-5 Paragraphs6-9 Paragraphs 10-12 Paragraphs 13
aridity and damage to animal habitat, as well as climate change and erosion change. Effect 1: Removing trees for commercial agriculture and subsistence farming can cause heavy erosion and flooding. Effect 2: Deforestation in the Amazon Basin will cause more emission of carbon dioxide, making the rainforest contribute to global warming. Effect 3:Forest destruction is also having an effect on biodiversity. Conclusion: Government should act to protect forests from illegal logging and planting more trees to absorb carbon dioxide.
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as a result the result of result in the effect of the consequence


hence because
due to

have an effect on the reason for the cause of It follows that
Development by Cause and Effect
1 Expressions often used for discussing cause and effect

of
so tly thus therefore accordingly because of for this reason owing to as a result since
My decision to live in an apartment during my first year of college had several negative effects. First, I lived with three girls from my country, so I did not improve my English because I spoke Chinese most of the time. Moreover, we took exactly the same classes, so I did not have chance to meet or study with my other classmates. Furthermore, since I did not have many American friends, I did not learn much about American culture. Finally, I did not share experience with people. So if I could change one thing about my first year in college, I would choose to live in the dormitory.
3 In-class Practice: A. Develop the following sentence into a paragraph by examining the causes.
We can surely have a friend of the opposite sex.
B. Develop the following sentence into a paragraph by mentioning or predicting the effects.
2 Two basic ways of organizing paragraphs developed by cause and effect Method 1:
Effect Cause 1 Cause 2 Cause 3
Method 2:
Cause Effect 1 Effect 2 Effect 3
I still remember the first day when I first came to this campus. Being a boy of 17, I was longing for a new life as a college student; at the same time, however, I had no idea what college life would be like. That morning when the bus carried me to the gate of the college, I was very excited. After registration, I were led by an instructor to the dormitory, where, for the first time, I was going to live without parents but roommates. I was so clumsy that I did not know how to make the bed and fix the mosquito net. In the afternoon, I took a walk around the campus together with my roommates. To think of studying in such a beautiful place made me feel quite proud of myself. As we were walking along, talking and laughing, a voice came into our ears, "Oh, look at these freshmen!" It was our middle-school-students' looking that gave us away. We continued our tour of the college, inspecting every building and every garden until the sun began to set. In the evening, we sat together, talking about the past and the future. We were so excited that no one wanted to go to bed.
In recent decades, cities have grown so large that now about 50% of the Earth's population lives in urban areas. There are several reasons for this occurrence. First, the increasing industrialization of the nineteenth century resulted in the creation of many factory jobs, which tended to be located in cities. These jobs, with their promise of a better material life, attracted many people from rural areas. Second, there were many schools established to educate the children of the new factory laborers. The promise of a better education persuaded many families to leave farming communities and move to the cities. Finally, as the cities grew, people established places of leisure, entertainment, and culture, such as sports stadiums, theaters, and museums. For many people, these facilities made city life appear more interesting than life on the farm, and therefore drew them away from rural communities.
Lecture 7. Development by Process



1. a chronological sequence 2.a step-by-step description 3.imperative sentences, pronoun you as the subject and the present tense are often used 4.words and phrases often used in writing process descriptions: occur before at this point become until at the same time happen while once as soon as grow as then take place be carried out change into
Once you encounter a person who has stopped breathing, you should begin immediately to do mouthto-mouth breathing. First, place the victim on his back and remove any foreign matter(杂质;异物) from his mouth with your fingers. Then tilt(使倾斜; 使翘起) his head backwards, so that his chin is pointing up. Next, pull his mouth open and his jaw forward, pinch his nostrils shut to prevent the air which you blow into his mouth from escaping through his nose. Then place your mouth tightly over the victim’s. Blow into his mouth until you see his chest rise. Then turn your head to the side and listen for the outrush of air which indicates an air exchange.
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