「華人戴明學院」是戴明哲學的學習共同體 ,致力於淵博型智識系統的研究、推廣和運用。 The purpose of this blog is to advance the ideas and ideals of W. Edwards Deming.

2016年1月27日 星期三

Ralph A. Evans (Feb 2, 1924–June 22, 2013)




王老師,新春氣爽!

建議您不要再提"三口.....",那是笑話,不談也罷。
我也是從IEEE 的Reliability 學刊讀到的。不過資料沒提此刊物,只提Reliability Symposium ---我們的中研院某院士也是靠此"二輪"雜誌的論文當選的。

這回您的記憶很好,他的大名和事業:

Ralph A. Evans - IEEE Xplore

ieeexplore.ieee.org/iel5/4906862/4914625/04914634.pdf?arnumber...
The R. A. Evans ─ P. K. McElroy Award for 2008 Best Paper. Ralph A. Evans. RalphEvans has served the Reliability Symposium and its predecessors and the  ...


165篇,RS學會有收集給會員,似未出書。

  • The RS is pleased to announce that we have added a new benefit for members of the Reliability Society.  We have compiled a collection of the Editorials from the legendary Dr. Ralph A. Evans, written during his tenure as Editor in Chief and Managing Editor of the T-Rel.  There are 165 Editorials, written between February 1969 and June of 1990.  When you read them, you can understand why the TRel  articles have such a long half-life (in excess of 10 years).  Most of the editorials are as relevant today as they were when they were written.  If you are an RS member and would like to see the compendium of Ralph's editorials, click the "About RS" tab, then click the "For Reliability Society Members Only" link in the left panel


他過世了:

In Memoriam Remembering Ralph A. Evans (Feb 2, 1924 ...

ieeexplore.ieee.org/iel7/24/6587537/06587564.pdf?arnumber...
by WAY KUO - ‎2013

In Memoriam 
Remembering Ralph A. Evans (Feb 2, 1924–June 22, 2013)

 THE IEEE Reliability Society, RAMS, and the reliability community at large benefitted greatly from the work of the late Dr. Ralph Evans. We will miss him very much and we mourn his passing. 

Ralph was tenacious, setting the standard for others to follow as an engineer, physicist, educator, and editor-in-chief and managing editor for the IEEE TRANSACTIONS ON RELIABILITY.

 Through his efforts, the TRANSACTIONS has become a great archival journal, arguably the best in the reliability field. By setting such high standards, he helped our contributors achieve a high degree of quality in their papers. He made sure every article was clear, correct, concise, and consistent, meeting the best of IEEE standards. He personally edited every accepted paper to appear in the TRANSACTIONS.

Through his great sense of humor, famous anecdotes, breathtaking wisdom, and in-depth knowledge, Ralph was able to bring to life the ideas that reliability engineers wished to pursue. He was best known for his many sayings, including such classics as:
 • making it easy to do the right thing and hard to do the wrong thing;
 • a type III error is the right solution to the wrong problem; 
• all models are wrong but some of them are useful; 
• too many papers repeat the old stuff, and too few papers bring in new insight. 

Combining high standards with his entertaining demeanor, Ralph was a great educator, too. The IEEE TRANSACTIONS ON RELIABILITY published many of his editorials, which were full of tutorial and textbook knowledge. 

Ralph defined reliability for IEEE for many years, being its leader for decades, having set the tone and standard for the publication even today, a full decade after he retired as managing editor. He received many awards over his long and distinguished career, too numerous to mention now, though we should remember that one award was even named after him. The IEEE awarded him the Centennial Medal, and he was made a Fellow, too. The Reliability Society awarded him its Annual Reliability Award in 1987.

 We appreciate his great work and spirit, and we are now tasked with maintaining the high standards that he set to help make the world a more reliable place. WAY KUO, Editor-in-Chief JASON RUPE, Managing Editor

2016年1月25日 星期一

Egyptian Museum Officials Face Tribunal for Damaging King Tutankhamen’s Mask

這是古物維護者品質和博物館環境問題。
中文標題沒將官員將受審翻譯出來。

埃及圖坦卡蒙黃金面具修復中受損

開羅——埃及行政檢察官表示,八名博物館員將面臨紀律審裁,因為他們對一次拙劣的圖坦卡蒙黃金面具修復工作負有責任。著名的圖坦卡蒙法老黃金喪葬面具是埃及最珍貴的文物之一,而前述修復工作給它造成了持久的損傷。
此次訴訟是一場發生在埃及博物館(Egyptian Museum)的尷尬事件的最新進展。事情始於2014年8月,當時開羅這座國家博物館的工人在修理面具展櫃里的一個燈具時,不慎將這件有3300年歷史的文物的鬍子撞掉,然後他們又試圖把鬍子粘回去,導致情況進一步惡化。
  • 檢視大圖圖坦卡蒙法老黃金面具在開羅的埃及博物館中展示。2014年8月,工人不慎撞掉了它的鬍鬚。
    Hassan Ammar/Associated Press
    圖坦卡蒙法老黃金面具在開羅的埃及博物館中展示。2014年8月,工人不慎撞掉了它的鬍鬚。
博物館員工使用不溶性環氧樹脂,將藍金兩色的鬍鬚粘回到面具上時,遊客拍下了他們的照片。修復行動在鬍鬚邊緣留下一圈明顯可見的膠水。有人擔心這種破壞是不可逆的,不過事實證明並非如此,德國專家小心翼翼地去除了環氧樹脂,並用古埃及人使用的粘接劑——蜂蠟——修復了純金面具。
上月,面具回到了公開展示區,不過工作人員最初嘗試用尖銳物體去除膠漬的時候,在面具上留下一些細微劃痕。負責調查涉公務員違法行為的行政檢察機關發表聲明,指控八名館員犯有「重大過失,公然違反科學和專業規則」,其中包括博物館的一名前任館長以及前修復工作負責人。
「為了掩蓋他們造成的破壞,他們用手術刀和金屬工具等鋒利的器械去除面具上的膠水痕迹,結果造成了持續的損傷和劃痕,」聲明稱。
遭到指控的館員已被停職,可能會面臨解僱和重金罰款,但不會入獄。
考古學家莫妮卡·漢娜(Monica Hanna)說,大多數遊客不會看到面具上的劃痕。她是旨在保護埃及文化遺產的文物工作組(Heritage Task Force)的成員。漢娜把這件事歸咎於埃及博物館的水平下降。這座博物館有104年歷史,是世界上最大的木乃伊和其他法老文物收藏館,但是近年來,它遭受了越來越嚴重的忽視。
「那裡的工作人員青黃不接,」她說。「經驗豐富的人退休了,新人又沒有接受過充分培訓。」
漢娜說,未來幾年,那裡的部分文物將被轉移到兩座新的博物館——一座是耗資8億美元的大埃及博物館(Grand Egyptian Museum),正在吉薩金字塔附近施工建設,計劃於2018年開放;另一座是已經竣工但尚未對公眾開放的埃及文明國家博物館(National Museum of Egyptian Civilization)。
1922年,英國考古學家霍華德·卡特(Howard Carter)在帝王谷發現了神秘的少年法老圖坦卡蒙的面具。從此之後,埃及古物學受到全球熱捧,成為埃及旅遊業的基石。
近年來,埃及旅遊業遭受了重創。最初是因為2011年埃及總統胡斯尼·穆巴拉克(Hosni Mubarak)倒台後發生的騷亂,然後在2013年,軍方推翻穆斯林兄弟會(Muslim Brotherhood)出身的總統穆罕默德·穆爾西(Mohamed Morsi)之後,埃及又出現了動蕩。
遊客遭到伊斯蘭極端分子的攻擊;八名墨西哥人被埃及安全部隊誤認為武裝分子並開槍射殺;去年10月,一架俄羅斯民航客機疑遭炸彈襲擊,224人命喪一處紅海度假勝地附近。
但是近幾個月來,圖坦卡蒙引起了新一輪的興趣,因為英國的埃及古物學者尼古拉斯·里夫斯(Nicholas Reeves)提出了一個很吸引人的假說,稱圖坦卡蒙的墓室背後隱藏着久尋不見的納芙蒂蒂王后(Queen Nefertiti)墓
翻譯:土土
Amina Ismail對本文有報道貢獻。

Egyptian Museum Officials Face Tribunal for Damaging King Tutankhamen’s Mask

The judicial action is the latest step in an embarrassing saga at the state-run Egyptian Museum in Cairo that started in August 2014 when workers accidentally knocked the beard from the 3,300-year-old artifact as they repaired a light fixture in its display case, and then made things worse by trying to glue it back on.
  • 檢視大圖The gold mask of King Tutankhamen in the Egyptian Museum in Cairo. Workers accidentally knocked the beard off in August 2014.
    Hassan Ammar/Associated Press
    The gold mask of King Tutankhamen in the Egyptian Museum in Cairo. Workers accidentally knocked the beard off in August 2014.
Tourists took photos of museum employees as they reattached the blue-and-gold beard using an insoluble epoxy resin that left a visible ring of glue around the edge of the beard. Fears that the damage was irreversible proved unfounded, however, after German experts carefully removed the epoxy and restored the solid gold mask using beeswax, the adhesive used by the ancient Egyptians.
The mask was returned to public display last month, albeit with some fine scratches caused by improvised earlier attempts to remove the glue stains using a sharp object. In a statement, the administrative prosecution authority, which investigates legal violations involving public servants, accused eight officials, including a former director of the museum and a former head of restoration, of “gross negligence and blatant violation of scientific and professional rules.”
“In an attempt to cover up the damage they inflicted, they used sharp instruments such as scalpels and metal tools to remove traces of the glue on the mask, causing damage and scratches that remain,” the statement said.
The accused officials have been suspended from their jobs and now face possible dismissal and heavy fines, but they will not go to prison.
The scratches to the mask will not be visible to most visitors, according to Monica Hanna, an archaeologist and a member of Egypt’s Heritage Task Force, an initiative to protect the nation’s cultural heritage. Ms. Hanna blamed the debacle on declining standards at the 104-year-old museum, which is home to the world’s largest collection of mummies and other Pharaonic antiquities but has become increasingly neglected in recent years.
“There’s been a shift in the people working there,” she said. “The experienced people have retired and the new ones do not have adequate training.”
Ms. Hanna said part of the collection was set to be shifted to two new museums in the coming years — the Grand Egyptian Museum, an $800 million project under construction near the Giza pyramids and scheduled to open in 2018, and the National Museum of Egyptian Civilization, which has been completed but is yet to open to the public.
The mask of Tutankhamen, an enigmatic young king, was discovered by the British archaeologist Howard Carter at the Valley of the Kings in 1922. It set off a global fascination with Egyptology that became a cornerstone of Egypt’s tourism industry.
That industry has suffered badly in recent years, first because of the unrest that followed the fall of President Hosni Mubarak in 2011, then because of the turmoil that erupted in 2013 after the military deposed President Mohamed Morsi of the Muslim Brotherhood.
Tourists have been attacked by Islamist extremists; eight Mexicans were killed by Egyptian security forces when they were mistaken for militants; and in October a suspected bomb brought down a Russian airliner, killing 224 people near a Red Sea resort.
In recent months, though, Tutankhamen became the focus of renewed interest after the British Egyptologist Nicholas Reeves promoted a tantalizing theory that behind his burial chamber lies the long-sought tomb of Queen Nefertiti.
Amina Ismail contributed reporting.

2016年1月21日 星期四

"Don't Eat Fortune's Cookie"成功與機遇,運氣與責任: Michael Lewis,2012年回母校普林斯頓演講

Ben Chen (陳健邦)
一位藝術史的研究生,何以進入Wall Street工作?再成為知名作家,rich and famous?
電影《魔球,Moneyball:The Art of Winning an Unfair Game》《大賣空,The Big Short》的原作者Michael Lewis,2012年回母校普林斯頓演講,給畢業生的人生建言:
"人生的幸運兒,不要為所謂成功的假象所矇蔽。"
其中的意義,也許要在職場生涯歷練多年的人,才能更深刻的體悟。
我想起陳之藩在《謝天》的句子:
"貪天之功,以為己力,是君子所不屑為的。"


Michael Lewis 2012 Commencement Speech at Princeton University 講者:Michael Lewis 2012年6月3日演講 翻譯:洪曉慧 編輯:朱學恆…
M.YOUTUBE.COM



HC: 感動:成功者的運氣與責任。各位應注意Michael Lewis先生說他現在 Rich and Famous 之後,頓一下,說"sort of",這是自我反諷的謙詞。他講的加州大學的實驗:領導/組長是任意選出的,不過卻理所當然、毫不慚愧地拿起最後一塊餅乾大嚼之。類似今日的華爾街大亨與各公司的執行長坐享高薪、待遇。
Michael Lewis 又說美國社會盲目崇拜成功者,完全忽略他們的運氣成份。他又舉他在Moneyball 一書說的,當時最富的洋基隊,給球員最好待遇,反而沒法找到懂得成功與機遇有關係的窮隊。


戴明:轉危為安
寓意的再詮釋。一位紐約大學學生,聽了我對上述主題做的演講,送給我下一段引言,並說出他的決心︰「從現在起,我對大將軍的功績,將採用不同的眼光來審視」︰
        關於大將軍的影響力及天才──有這樣一則故事,恩里科•費米(Enrico Fermi)曾向萊斯利˙格羅夫斯(Leslie Groves)將軍問道︰有多少將軍可以稱之為「偉大」?格羅夫斯回答說︰大約3%。費米隨後問道︰什麼是「偉大」的條件,格羅夫斯回答說︰任何一位將軍在連續贏得5次戰役後,就可稱之為偉大。這是二次世界大戰的中期。費米說︰在考慮過大多數戰場的反抗力量,大約與攻方是相等的,這位將軍可能在2場戰役中贏1場,有14的機會可以連續贏2場,有18的機會可連續贏3場,有116的機會可以連續贏4場,有132的機會可以連續贏5場。「將軍,你是對的,大約有3% 的機會,這是數學概率,並不是天才。」(約翰‧基岡(John Keegan)著,《戰爭的面目》,維京(Viking)出版公司,1977年。)


Web Stories

Princeton University's 2012 Baccalaureate Remarks

"Don't Eat Fortune's Cookie"
Michael Lewis
June 3, 2012 — As Prepared
(NOTE: The video of Lewis' speech as delivered is available on the Princeton YouTube channel.)
Thank you. President Tilghman. Trustees and Friends. Parents of the Class of 2012. Above all, Members of the Princeton Class of 2012. Give yourself a round of applause. The next time you look around a church and see everyone dressed in black it'll be awkward to cheer. Enjoy the moment.
Thirty years ago I sat where you sat. I must have listened to some older person share his life experience. But I don't remember a word of it. I can't even tell you who spoke. What I do remember, vividly, is graduation. I'm told you're meant to be excited, perhaps even relieved, and maybe all of you are. I wasn't. I was totally outraged. Here I’d gone and given them four of the best years of my life and this is how they thanked me for it. By kicking me out.  
At that moment I was sure of only one thing: I was of no possible economic value to the outside world. I'd majored in art history, for a start. Even then this was regarded as an act of insanity. I was almost certainly less prepared for the marketplace than most of you. Yet somehow I have wound up rich and famous. Well, sort of. I'm going to explain, briefly, how that happened. I want you to understand just how mysterious careers can be, before you go out and have one yourself.
I graduated from Princeton without ever having published a word of anything, anywhere. I didn't write for the Prince, or for anyone else. But at Princeton, studying art history, I felt the first twinge of literary ambition. It happened while working on my senior thesis. My adviser was a truly gifted professor, an archaeologist named William Childs. The thesis tried to explain how the Italian sculptor Donatello used Greek and Roman sculpture — which is actually totally beside the point, but I've always wanted to tell someone. God knows what Professor Childs actually thought of it, but he helped me to become engrossed. More than engrossed: obsessed. When I handed it in I knew what I wanted to do for the rest of my life: to write senior theses. Or, to put it differently: to write books. 
Then I went to my thesis defense. It was just a few yards from here, in McCormick Hall. I listened and waited for Professor Childs to say how well written my thesis was. He didn't. And so after about 45 minutes I finally said, "So. What did you think of the writing?"
"Put it this way" he said. "Never try to make a living at it."
And I didn't — not really. I did what everyone does who has no idea what to do with themselves: I went to graduate school. I wrote at nights, without much effect, mainly because I hadn't the first clue what I should write about. One night I was invited to a dinner, where I sat next to the wife of a big shot at a giant Wall Street investment bank, called Salomon Brothers. She more or less forced her husband to give me a job. I knew next to nothing about Salomon Brothers. But Salomon Brothers happened to be where Wall Street was being reinvented—into the place we have all come to know and love. When I got there I was assigned, almost arbitrarily, to the very best job in which to observe the growing madness: they turned me into the house expert on derivatives. A year and a half later Salomon Brothers was handing me a check for hundreds of thousands of dollars to give advice about derivatives to professional investors.  
Now I had something to write about: Salomon Brothers. Wall Street had become so unhinged that it was paying recent Princeton graduates who knew nothing about money small fortunes to pretend to be experts about money. I'd stumbled into my next senior thesis.
I called up my father. I told him I was going to quit this job that now promised me millions of dollars to write a book for an advance of 40 grand. There was a long pause on the other end of the line. "You might just want to think about that," he said. 
"Why?"
"Stay at Salomon Brothers 10 years, make your fortune, and then write your books," he said.  
I didn't need to think about it. I knew what intellectual passion felt like — because I'd felt it here, at Princeton — and I wanted to feel it again. I was 26 years old. Had I waited until I was 36, I would never have done it. I would have forgotten the feeling.   
The book I wrote was called "Liar’s Poker."  It sold a million copies. I was 28 years old. I had a career, a little fame, a small fortune and a new life narrative. All of a sudden people were telling me I was born to be a writer. This was absurd. Even I could see there was another, truer narrative, with luck as its theme. What were the odds of being seated at that dinner next to that Salomon Brothers lady? Of landing inside the best Wall Street firm from which to write the story of an age? Of landing in the seat with the best view of the business? Of having parents who didn't disinherit me but instead sighed and said "do it if you must?" Of having had that sense of must kindled inside me by a professor of art history at Princeton? Of having been let into Princeton in the first place?
This isn't just false humility. It's false humility with a point. My case illustrates how success is always rationalized. People really don’t like to hear success explained away as luck — especially successful people. As they age, and succeed, people feel their success was somehow inevitable. They don't want to acknowledge the role played by accident in their lives. There is a reason for this: the world does not want to acknowledge it either. 
I wrote a book about this, called "Moneyball." It was ostensibly about baseball but was in fact about something else. There are poor teams and rich teams in professional baseball, and they spend radically different sums of money on their players. When I wrote my book the richest team in professional baseball, the New York Yankees, was then spending about $120 million on its 25 players. The poorest team, the Oakland A's, was spending about $30 million. And yet the Oakland team was winning as many games as the Yankees — and more than all the other richer teams.  
This isn't supposed to happen. In theory, the rich teams should buy the best players and win all the time. But the Oakland team had figured something out: the rich teams didn't really understand who the best baseball players were. The players were misvalued. And the biggest single reason they were misvalued was that the experts did not pay sufficient attention to the role of luck in baseball success. Players got given credit for things they did that depended on the performance of others: pitchers got paid for winning games, hitters got paid for knocking in runners on base. Players got blamed and credited for events beyond their control. Where balls that got hit happened to land on the field, for example.
Forget baseball, forget sports. Here you had these corporate employees, paid millions of dollars a year. They were doing exactly the same job that people in their business had been doing forever.  In front of millions of people, who evaluate their every move. They had statistics attached to everything they did. And yet they were misvalued — because the wider world was blind to their luck. 
This had been going on for a century. Right under all of our noses. And no one noticed — until it paid a poor team so well to notice that they could not afford not to notice. And you have to ask: if a professional athlete paid millions of dollars can be misvalued who can't be? If the supposedly pure meritocracy of professional sports can't distinguish between lucky and good, who can? 
The "Moneyball" story has practical implications. If you use better data, you can find better values; there are always market inefficiencies to exploit, and so on. But it has a broader and less practical message: don't be deceived by life's outcomes. Life's outcomes, while not entirely random, have a huge amount of luck baked into them. Above all, recognize that if you have had success, you have also had luck — and with  luck comes obligation. You owe a debt, and not just to your Gods. You owe a debt to the unlucky.
I make this point because — along with this speech — it is something that will be easy for you to forget.
I now live in Berkeley, California. A few years ago, just a few blocks from my home, a pair of researchers in the Cal psychology department staged an experiment. They began by grabbing students, as lab rats. Then they broke the students into teams, segregated by sex. Three men, or three women, per team. Then they put these teams of three into a room, and arbitrarily assigned one of the three to act as leader. Then they gave them some complicated moral problem to solve: say what should be done about academic cheating, or how to regulate drinking on campus.
Exactly 30 minutes into the problem-solving the researchers interrupted each group. They entered the room bearing a plate of cookies. Four cookies. The team consisted of three people, but there were these four cookies. Every team member obviously got one cookie, but that left a fourth cookie, just sitting there. It should have been awkward. But it wasn't. With incredible consistency the person arbitrarily appointed leader of the group grabbed the fourth cookie, and ate it. Not only ate it, but ate it with gusto: lips smacking, mouth open, drool at the corners of their mouths. In the end all that was left of the extra cookie were crumbs on the leader's shirt.
This leader had performed no special task. He had no special virtue. He'd been chosen at random, 30 minutes earlier. His status was nothing but luck. But it still left him with the sense that the cookie should be his.  
This experiment helps to explain Wall Street bonuses and CEO pay, and I'm sure lots of other human behavior. But it also is relevant to new graduates of Princeton University. In a general sort of way you have been appointed the leader of the group. Your appointment may not be entirely arbitrary. But you must sense its arbitrary aspect: you are the lucky few. Lucky in your parents, lucky in your country, lucky that a place like Princeton exists that can take in lucky people, introduce them to other lucky people, and increase their chances of becoming even luckier. Lucky that you live in the richest society the world has ever seen, in a time when no one actually expects you to sacrifice your interests to anything. 
All of you have been faced with the extra cookie. All of you will be faced with many more of them. In time you will find it easy to assume that you deserve the extra cookie. For all I know, you may. But you'll be happier, and the world will be better off, if you at least pretend that you don't. 
Never forget: In the nation's service. In the service of all nations.
Thank you. 

And good luck.   







2016年1月19日 星期二

英國大選的預測大錯誤?quota sampling instead random sampling

Election polling errors blamed on 'unrepresentative' samples

    The failure of pollsters to forecast the outcome of the general election was largely due to "unrepresentative" poll samples, an inquiry has found.
    The polling industry came under fire for predicting a virtual dead heat when the Conservatives ultimately went on to outpoll Labour by 36.9% to 30.4%.
    A panel of experts has concluded this was due to Tory voters being under-represented in phone and online polls.
    But it said it was impossible to say whether "late swing" was also a factor.
    The majority of polls taken during last year's five-week election campaign suggested that David Cameron's Conservatives and Ed Miliband's Labour were neck-and-neck.
    This led to speculation that Labour could be the largest party in a hung parliament and could potentially have to rely on SNP support to govern.
    But, as it turned out, the Conservatives secured an overall majority in May for the first time since 1992, winning 99 more seats than Labour, their margin of victory taking nearly all commentators by surprise.

    'Statistical consensus'

    The result prompted the polling industry to launch an independent inquiry into the accuracy of their research, the reasons for any inaccuracies and how polls were analysed and reported.
    Graphic showing how the results of the 2015 general election for Labour and the Conservatives compared to the poll predictions. The polls predicted Labour would receive 33% of the vote share, while the Tories would get 34%. However, the Tories won 36.9% and Labour got just 30.5%.
    An interim report by the panel of academics and statisticians found that the way in which people were recruited to take part - asking about their likely voting intentions - had resulted in "systematic over-representation of Labour voters and under-representation of Conservative voters".
    These oversights, it found, had resulted in a "statistical consensus".

    How opinion polls work

    Exit poll results projected onto BBC Broadcasting House in LondonImage copyrightAFP
    Image captionThe exit poll conducted on election day itself came much closer to the ultimate result than any of those conducted in the run-up
    Most general election opinion polls are either carried out over the phone or on the internet. They are not entirely random - the companies attempt to get a representative sample of the population, in age and gender, and the data is adjusted afterwards to try and iron out any bias, taking into account previous voting behaviour and other factors.
    But they are finding it increasingly difficult to reach a broad enough range of people. It is not a question of size - bigger sample sizes are not necessarily more accurate.
    YouGov, which pays a panel of thousands of online volunteers to complete surveys, admitted they did not have access to enough people in their seventies and older, who were more likely to vote Conservative. They have vowed to change their methods.
    Telephone polls have good coverage of the population, but they suffer from low response rates - people refusing to take part in their surveys, which can lead to bias.
    BBC poll of polls on 6 May 2015

    This, it said, was borne out by polls taken after the general election by the British Election Study and the British Social Attitudes Survey, which produced a much more accurate assessment of the Conservatives' lead over Labour.
    NatCen, who conducted the British Social Attitudes Survey, has described making "repeated efforts" to contact those it had selected to interview - and among those most easily reached, Labour had a six-point lead.
    However, among the harder-to-contact group, who took between three and six calls to track down, the Conservatives were 11 points ahead.

    'Herding'

    Evidence of a last-minute swing to the Conservatives was "inconsistent", the experts said, and if it did happen its effect was likely to have been modest.
    Former Lib Dem leader Nick Clegg has suggested such a swing, ascribing it to voters' fears about a hung parliament and a possible Labour-SNP tie-up.
    It also downplayed other potential explanations such as misreporting of voter turnout, problems with question wording or how overseas, postal or unregistered voters were treated in the polls.
    However, the panel said it could not rule out the possibility of "herding" - where firms configured their polls in a way that caused them to deviate less than could have been expected from others given the sample sizes. But it stressed that did not imply malpractice on behalf of the firms concerned.
    Prof Patrick Sturgis, director of the National Centre for Research Methods at the University of Southampton and chair of the panel, told the BBC: "They don't collect samples in the way the Office for National Statistics does by taking random samples and keeping knocking on doors until they have got enough people.
    "What they do is get anyone they can and try and match them to the population... That approach is perfectly fine in many cases but sometimes it goes wrong."
    Prof Sturgis said that sort of quota sampling was cheaper and quicker than the random sampling done by the likes of the ONS, but even if more money was spent - and all of the inquiry's recommendations were all implemented - polls would still never get it right every time.

    Analysis by the BBC's political editor Laura Kuenssberg
    Ed Miliband resigning after the 2015 general electionImage copyrightEPA
    I remember the audible gasp in the BBC's election studio when David Dimbleby read out the exit poll results.
    But for all that the consequences of that startling result were many and various, the reasons appear remarkably simple.
    Pollsters didn't ask enough of the right people how they planned to vote. Proportionately they asked too many likely Labour voters, and not enough likely Conservatives
    Politics is not a precise science and predicting how people will vote will still be a worthwhile endeavour. Political parties, journalists, and the public of course would be foolish to ignore them. But the memories and embarrassment for the polling industry of 2015 will take time to fade.

    Joe Twyman, from pollster YouGov, told the BBC it was becoming increasingly difficult to recruit people to take part in surveys - despite, in YouGov's case, paying them to do so - but all efforts would be made to recruit subjects in "a more targeted manner".
    "So more young people people who are disengaged with politics, for example, and more older people. We do have them on the panel, but we need to work harder to make sure they're represented sufficiently because it's clear they weren't at the election," he said.
    Pollsters criticised for their performance have pointed to the fact that they accurately predicted the stellar performance of the SNP in Scotland - which won 56 out of 59 seats - and the fact that the Lib Dems would get less than 10% of the vote and be overtaken by UKIP.


2015.5.17
我們靜待British Polling Council (BPC)專業分析報告。

Predicting the result
Pollderdash 看不懂標題。
Why the opinion polls went wrong
May 16th 2015 | From the print edition




IT WAS supposed to be the closest general election for several decades. At least ten final opinion polls put the Conservative and Labour parties within a percentage point of each other. Politicians were being told firmly that some kind of coalition government was inevitable. But all that turned out to be wrong. The Tories ended seven points ahead of Labour in the popular vote and won a majority in the House of Commons. Why were the projections wrong?

In 1992 pollsters made a similar error, putting Labour slightly ahead on the eve of an election that the Tories won by eight points. The often-cited explanation for this mistake is so-called “shy Tories”—blue voters who are ashamed to admit their allegiance to pollsters. In fact that was just one of several problems: another was that the census data used to make polling samples representative was out of date.


Following an inquiry, pollsters improved. A similar review has now been launched by the British Polling Council (BPC), but its conclusions may be less clear cut. In 1992 all the pollsters went wrong doing the same thing, says Joe Twyman of YouGov. This time they went wrong doing different things. Some firms contact people via telephone, others online, and they ask different questions. Statistical methods are hotly debated.

That has led to almost as many explanations for the error as there are polling firms. The “shy Tories” might have reappeared, but this cannot explain the whole picture. Ipsos MORI, for instance, only underestimated the Tory share of the vote by one percentage point—but it overestimated support for Labour. Bobby Duffy, the firm’s head of social research, says turnout might explain the miss. Respondents seemed unusually sure they would vote: 82% said they would definitely turn out. In the event only 66% of electors did so. The large shortfall may have hurt Labour more.

Others reckon there was a late swing to the Tories. Patrick Briône of Survation claims to have picked this up in a late poll which went unpublished, for fear that it was an outlier 異常值. Polls are often conducted over several days; Mr Briône says that slicing up the final published poll by day shows movement to the Tories, too. Yet this is contradicted by evidence from YouGov, which conducted a poll on election day itself and found no evidence of a Tory surge.

One firm, GQR, claims to have known all along that Labour was in trouble. The polls it conducted privately for the party consistently showed Labour trailing. Unlike most other pollsters, GQR “warms up” respondents by asking them about issues before their voting intention. Pollsters tend to be suspicious of so-called “priming” of voters, which seems just as likely to introduce bias as to correct it.

The BPC’s inquiry will weigh up the competing theories. Given the range of methods and the universal error, a late surge seems the most plausible explanation for now. That would vindicate Lynton Crosby, the Tory strategist, who insisted voters would turn blue late on. Next time expect more scepticism about polls—and more frantic last-minute campaigning.

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