【正文】 問： ? 1） 4個(gè)樣品中剛好有一個(gè)不合格的概率是多少？ ? 2）不超過 2個(gè)不合格零件的概率是多少？ ? 提示：超幾何分布 ? 答案： ， End of Chapter 5 。試求 ? 1）為發(fā)現(xiàn)一例患色盲者，至少要檢查 25個(gè)婦女的概率。 ? 1/? = the mean time between events (??0). 0,)( ?? ? xexf x??? Relationship between the Poisson and Exponential Distributions 泊松分布描述特定時(shí)間或空間間隔中，事件發(fā)生的次數(shù)服從的分布 (If) the Poisson distribution provides an appropriate description of the number of occurrences per interval (If) the exponential distribution provides an appropriate description of the length of the interval between occurrences () !x efx x?? ??Example 假設(shè) 1小時(shí)內(nèi)到達(dá)洗車行的汽車數(shù)服從泊松分布，均值為每小時(shí)10輛。 b=upper limit of the interval from a to b。 ? b=upper limit of the interval from a to b。s use of a coded ：銀行使用的能對(duì)委托人持用的有密碼的卡片作出反應(yīng)并自動(dòng)進(jìn)行個(gè)人財(cái)產(chǎn)交易的機(jī)器 ? (4)A person appointed to count votes in a legislative ：被指派在議會(huì)中數(shù)票的人 541 Vocabularies ? teller ? automatic(al) teller 銀行自動(dòng)機(jī) ? coupon teller 息票付款員 ? deposit teller 收款員 ? discount tellers 貼現(xiàn)人員 ? exchange teller 匯兌員 , 匯兌股人員 ? moisture teller 水分快速測(cè)定儀（ moisture 潮濕，濕氣） ? note teller (銀行 )票據(jù)員 ? paying teller 付款員 ? receiving teller 收款員 541 Vocabularies ? interval ? （ 1） A space between two objects, points, or units. ? 間隔，空隙：兩上物體、點(diǎn)、或構(gòu)件之間的空間 ? （ 2） Mathematics A set of numbers consisting of all the numbers between a pair of given numbers. ? 【 數(shù)學(xué) 】 區(qū)間：由一對(duì)已知數(shù)之間所有數(shù)組成的一組數(shù) ? A set of numbers consisting of all the numbers between a pair of given numbers and including the called ? closed interval 閉區(qū)間 ? A set of numbers consisting of all the numbers between a pair of given numbers but not including the called ? open interval 開區(qū)間 542 Main Content ? the uniform probability distribution ? Where: f(x)=value of the density function at any x value。 ? (2)；路邊服務(wù)式的 (飯店、電影院等 )。 lapse:過去；逝去： ? met again after an elapse of many years.(翻譯 ) ? 多年后又相逢 541 Vocabularies ? drivein ? (1) establishment designed to permit customers to remain in their motor vehicles while being ：顧客接受服務(wù)時(shí)可不下車的營(yíng)業(yè)場(chǎng)所或娛樂設(shè)施（如免下車餐館 , 免下車電影院） ? [美 ](讓顧客不下汽車即可吃飯、辦事、看戲等的 )路旁餐館[銀行 ], 露天電影院 ? 39。n,p) of the binomial distribution or from Table when n is small. In addition, binomial probabilities are readily available in many software puter packages. However, it is instructive to learn the relationship between the binomial and normal distribution. In section we illustrated how the Poisson distribution can be used to approximate binomial probabilities when n is quite large and p is very close to 0 or 1. both the binomial and Poisson distributions are discrete. 534 After school extend ? normal approximation to the binomial（接前頁） ? The first application of a continuous probability distribution to approximate probabilities over a discrete sample space is demonstrated by example , where the normal curve was used. The normal distribution is often a good approximation to a discrete distribution when the latter takes on a symmetric bell shape. From a theoretical point of view, some distributions converge to the normal as their parameters approach certain limits. The normal distribution is a convenient approximating distribution because the cumulative distribution function is so easily tabled. 54 Other Continuous Probability Distributions ? 541 Vocabularies 詞匯 ? 542 Main Content 主要內(nèi)容 ? 543 Terminologies 專業(yè)詞匯 ? 544 After school extend 課外擴(kuò)展 ? 545 Literature 文獻(xiàn)導(dǎo)讀 541 Vocabularies ? elapse ? To slip by。 ? 采用正態(tài)近似 ? 計(jì)算概率 1 2 ( 1 0 0 1 2 )1 0 0 !( 1 2 ) 0 . 1 ( 1 0 . 1 )1 2 ! ( 1 0 0 1 2 ) !f????21 0 0 0 . 1 1 0 , ( 1 ) 1 0 0 ( 1 0 . 1 ) 9 01 0 0 0 . 1 1 0( 1 0 , 3 )( 1 ) 1 0 0 0 . 1 ( 1 0 . 1 ) 3n p n pnpxNn p p?s? ? ? ? ? ? ? ?? ? ? ??? ? ? ? ? ? ?， 滿 足 條 件 。 f x nx n x p px n x( ) !! ( ) ! ( ) ( )? ? ? ?1( , ( 1 ) )x N n p n p p?Example 假定歷史經(jīng)驗(yàn)表明，某公司發(fā)票出錯(cuò)的概率為 10%。 = minutes, s = minutes ? 1) Greater than minutes P(x ) = P(z )= .5 – .3413 = ? 2) Less than minutes P(x ) = P(z –)= .5 – .4772 = z ? x – ? s ? 14 . 1 – 12 . 1 2 . 0 ? 1 . 00 z ? x – ? s ? 8 . 1 – 12 . 1 2 . 0 ? – 2 . 00 Example: Using Microsoft Excel ? Problem: What is the probability that the time required for Mary and her bags to get to the room will be: 3) between and minutes? In a cell on an Excel worksheet, type all on one line =NORMDIST(,2,true) NORMDIST(,2,true) and you will see the answer: 4) between and minutes? In a cell on an Excel worksheet, type all on one line =NORMDIST(,2,true) NORMDIST(,2,true) and you will see the answer: 532 Main Content ? approximate areas under the normal curve ? There are some general rules: ? (1) encloses about 68% of X’s ? (2) encloses about 95% of X’s ? (3) encloses about 99% of X’s 2?s?1?s?3?s?532 Main Content 二項(xiàng)分布的正態(tài)近似 ? Binomial Probability Function ? 當(dāng)實(shí)驗(yàn)次數(shù)很大時(shí)，用手工計(jì)算或計(jì)算器計(jì)算求解二項(xiàng)概率函數(shù)是困難的。為該畜牧業(yè)區(qū)中的工業(yè)中心。化學(xué)工業(yè)為其經(jīng)濟(jì)的主要支柱。 customers are satisfied with your last shipment. ? (7)shipping n. 海運(yùn) ? Eg. Shipping instruction 裝船要求； shipping advice 裝船通知； shipping documents 裝船單據(jù)； shipping space 艙位 ? (8)shipper 53 The Normal