June 23rd, 2015 (Permalink)
Poll Watch: Much Ado about Nothing Much
We're over a year away from the next presidential election, and even the earliest state primaries are more than a half-year away, but apparently it's not too soon to start polling. The primaries and conventions are so distant that it's unlikely that a poll will tell us much even about who will be nominated, let alone about who will win in November of next year. Nonetheless, here is the headline of a news article about a recent poll:
Walker leads nationally in new poll
What does that mean? Does it mean that Governor Scott Walker of Wisconsin is ahead of Hillary Clinton in the poll? Not at all. Here are the first two paragraphs of the article following the headline:
Wisconsin Gov. Scott Walker leads a tight field of candidates for the Republican presidential nomination, according to a new survey from Public Policy Polling. Walker is alone in first place in the poll with 17 percent, followed by former Florida Gov. Jeb Bush at 15 percent, Sen. Marco Rubio (Fla.) at 13 percent, retired neurosurgeon Ben Carson at 12 percent and former Arkansas Gov. Mike Huckabee at 11 percent.
Source: Jonathan Easley, "Walker leads nationally in new poll", The Hill, 6/16/2015
Now, if you know that almost all national public opinion polls have a margin of error (MoE) of at least plus-or-minus three percentage points, you'll immediately spot a problem here: The difference between Walker and his nearest competitor, Jeb Bush, is only two percentage points, which is within the MoE. Similarly, the difference between Bush and the next candidate, Senator Marco Rubio, is also two percentage points. Finally, Rubio differs from the following candidate, Ben Carson, by a single percentage point, and Carson is only one point ahead of Mike Huckabee. Thus, none of the differences between any of the top five candidates and their nearest competitors is statistically significant.
However, the situation is worse than that, though this particular article does not supply the relevant information. For that information, you have to go to the report on the poll put out by Public Policy Polling―see the Source, below. At the end of The Hill article, we're told that 1,129 people were polled for a MoE of 2.9 percentage points, which is about what we would expect. However, as we learn from the polling report itself, the comparisons of the Republican candidates came from a subsample of 429 Republican voters, and so the MoE for these results is actually ±4.4 points. Thus, Walker, Bush, and Rubio are all within the MoE of one another.
What can we learn from this poll and the reporting of it?
- The news media usually report poll results as races with winners and losers even when there is no clear winner. Reporters frequently treat poll results as if they are perfectly precise, despite mentioning the MoE at the end of the article. Whether this is because of a lack of understanding of the MoE, or they ignore it in the interest of making a more dramatic and exciting story, the result is the same.
- At this early date, it's likely that most Republican voters have not paid sufficient attention to the campaign to choose a favorite candidate, and the poll results showing several candidates close together probably reflects that fact.
- Because it's so early in the race, there may be hundreds of national political polls between now and November of next year. Because of the 95% confidence level used to determine the MoE in polling, we can expect 5% of these polls to have results that differ from reality by greater than the MoE. Thus, there are bound to be tens, and perhaps scores, of polls before voting is over that will be outliers. With so many polls being conducted, it's very important to compare poll results: if a given poll shows very different results from others conducted around the same time, it's most likely that the outlier is wrong.
Source: "Walker, Bush, Rubio lead GOP Field Nationally, Clinton Still Dominant", Public Policy Polling, 6/16/2015
Resource: How to Read a Poll
June 5th, 2015 (Permalink)
The Case of the Puzzling Statement
A suspect was arrested on a charge of murder. When interrogated by the police, the suspect volunteered to write a statement if he was left alone with a sheet of paper and a pen. The police proceeded to do so, but a lawyer hired by the suspect's wife showed up soon thereafter, demanding to see the suspect in private. Afterward, the suspect refused to write or say anything further on the advice of his attorney. All that was written on the piece of paper was the following:
If the victim was asleep when I arrived but the front door was locked, or the back door was open, then either I killed him or both a light was on in his room near midnight and the murder weapon was a gun, unless neither was he drunk when he died nor was the murder weapon a knife.
Unsurprisingly, the police are baffled by this statement and have very little evidence against the suspect. All that they know for sure is that the victim was not shot but killed with a knife, and that the back door had been left open. If they can't decipher the cryptic statement, the suspect will surely walk. Can you help the police make sense of the suspect's statement?
Assuming that the suspect's statement is true, and that the evidence gathered by the police is correct―that is, that the victim was killed with a knife, not a gun, and the back door was open―can you determine whether or not the suspect killed the victim? If you think you know the answer, click on "Solution", below, to find out if you cracked the case.
June 2nd, 2015 (Permalink)
New Book: Spinglish
"Spinglish" is a combination of the words "spin" and "English"―in analogy to the more familiar term "Spanglish"―describing English words and phrases used to "spin". Henry Beard and Christopher Cerf have produced a book of that title, subtitled The Definitive Dictionary of Deliberately Deceptive Language. Beard and Cerf are best known for writing humor books, so I'm not sure how serious a work this is. Also, having not yet read it, I don't know whether it adds anything much to William Lutz' doublespeak dictionary, or Steven Poole's Unspeak. Some of the words and definitions I've seen attributed to the book were discussed previously by Lutz or Poole. However, I do think it will be a useful reference even if it just gathers together all of the examples from previous writers in dictionary form together with citations.
- Henry Beard & Christopher Cerf, Spinglish: The Definitive Dictionary of Deliberately Deceptive Language (2015)
- Ron Charles, "‘Spinglish,’ by Henry Beard and Christopher Cerf", The New York Times, 5/23/2015
Update (6/27/2015): There's an excerpt from Spinglish in The Daily Beast consisting of the introduction and all of the entries in the book that fall under the letter "G"―see Source 1, below.
Some of the words are new to me, such as "gallerist", which is an inflated term for "art dealer"; others are familiar, for instance, "gaming" used as a general euphemism for the more specific "gambling"―William Lutz includes it in his 1999 book Doublespeak Defined, see Source 2, below. I wrote about "government relations professional" back when it was in the news as a proposed euphemism for "lobbyist"―see the Resource, below.
Some of the definitions are themselves tendentious, for example, "[t]he hunting or mass slaughter of wild animals" as a definition of "game management". It's true that "game management" is often used as a euphemism for the more specific "hunting", but throwing in "mass slaughter" adds nothing to the definition but emotional bias against hunting as a means of controlling the population of animals. Moreover, if you're going to include "gun grabber" as "[a] term for someone who supports gun control legislation favored by those who don’t", why not include "gun nut" as "a term for someone who opposes gun control legislation favored by those who support it"? There seems to be a degree of spin in what counts as "spinglish".
However, some of these words are not like the others; some of these words just don't belong. For instance, "greenwashing" is not a euphemism, but if anything the opposite, since it's used by environmentalists to condemn businesses that promote their practices as "green" when they're really not. This is a problem with introducing a new word, such as "spinglish" or "unspeak", no matter how clever and amusing it may be: unless such a word is precisely defined, it's hard to know what counts as an instance. The closest that Beard and Cerf come to defining "spinglish" seems to be the following passage from the introduction:
But what precisely is Spinglish? Well, in spite of its polyglot-sounding name, it isn’t some foreign language. It’s just our native tongue, transformed into a sophisticated method of judicious miscommunication through the use of careful word choice and the artful rephrasing and reframing of familiar terms. To put it another way (which, of course, is what Spinglish is designed to do), it all comes down to making me sound better, or you sound worse, or both.
Unfortunately, that isn't a very precise answer. "Careful word choice" and "artful rephrasing" are characteristics of good writing. The only real help in this "definition" is that it characterizes spinglish as "a sophisticated method of judicious miscommunication". In other words, what seems to separate spinglish from good English is that the latter aims at communication whereas the former's goal is obfuscation. However, it's perfectly possible to mislead people without using the euphemisms, doublespeak, loaded language, and weasel words that seem to constitute most of the entries in this book.
"Greenwashing" doesn't seem to meet this vague definition, since it serves as a label for a certain type of spin. If "greenwashing" is spinglish, then would "spinglish" itself count as spinglish?
I hope I don't sound too much like a pedantic killjoy. Beard and Cerf might well reply that their book is intended as amusing and entertaining light reading rather than a scholarly monograph, and my goal is not to spoil anyone's enjoyment of it, but to point that out.
- Henry Beard & Christopher Cerf, "How to Translate ‘Spinglish’", The Daily Beast, 6/23/2015
- William Lutz, Doublespeak Defined: Cut Throught the Bull**** and Get the Point (1999), p. 153
Resource: Doublespeak Dictionary, 9/24/2013
May 28th, 2015 (Permalink)
Cross-Check it Out
On October 28th, 2000, President Bill Clinton, in his weekly radio address made the following claims about the incidence of domestic violence against women in the United States:
Every 12 seconds another woman is beaten. That’s nearly 900,000 victims every year.
Source: "The President’s Radio Address", Government Printing Office, 10/28/2000 (PDF)
Are these numerical claims plausible? How could you go about checking them? Is there any way to do so without doing any research, that is, just using what you already know? When you've done your own plausibility check, click on "Check it Out", below, to see one way of checking these numbers.
Source: David Murray, Joel Schwartz & S. Robert Lichter, It Ain't Necessarily So: How Media Make and Unmake the Scientific Picture of Reality (2001), pp. xiii-xv.
May 26th, 2015 (Permalink)
Food is a Fallacy
Fads, I submit, are the very negation of reason. To be swept up in every new craze that comes along, to surrender oneself to idiocy just because everybody else is doing it―this to me, is the acme of mindlessness.
Source: Max Shulman, "Love is a Fallacy"
Slate had an article about a month ago, but which I just discovered, on the fallacious thinking behind food fads. Here's a taste:
Natural food is good. Evil foods harm you, but they are sinfully delicious, guilty pleasures. Good foods, on the other hand, are real and clean. … We’ve been primed to think this way. After all, the world’s most famous myth recounts a dietary fall from grace. Long ago, humans lived in an organic, all-natural, divinely designed garden, free from pesticides and GMOs and processed grains and sugar. But one day an evil advertiser came along and hissed, “Just eat this fruit.” Bam! Suddenly we were cursed with mortality, marital strife, labor pains, and agriculture. … Consider…“love of nature,” which is used to justify virtually every diet on the market, from gluten-free (modern Frankenwheat is unnatural!) to raw food (cooking is unnatural!). It turns out that the “appeal to nature” is a well-established fallacy, plagued by question begging…in addition to the inherent vagueness of the term natural. Nevertheless, people demand all-natural foods and dutifully avoid unnatural chemicals, oblivious to the irrational foundation of their preferences.
Source: Alan Levinovitz, "The Logical Failures of Food Fads", Slate, 4/21/2015
Try it, you might like it. The author is, of course, promoting a new book, and Harriet "The Skepdoc" Hall has a favorable review of it. Here's a tasty bite:
To many people science is suspect because of the steady stream of scientific reversals on butter, wine, or whatever food appears in the headlines. But [Levinovitz] points out that these are not reversals at all, because nothing was ever established in the first place. The headlines report single preliminary studies that are questionable, not scientific consensus based on an accumulated body of reliable data. True science is humble, cautious, and embraces complexity and uncertainty.
Source: Harriet Hall, "Food Faiths & Diet Religions", Eskeptic, 5/20/2015
Update: Entirely by coincidence, as far as I know, Brian Dunning of Skeptoid has a podcast today on fads. Not all of the fads that he discusses concern food, but he does deal with juice fads, the dangerous practice of drinking unpasteurised milk, and the anti-gluten hysteria that provides Levinovitz' book its title. Here's a nibble to whet your appetite:
It's hard to say this often enough. Aches and pains usually eventually go away; that's the natural effect of our bodies healing themselves. When they do, our brains tend to credit whatever it was we were doing at the time. …. This is why scientists know that anecdotal experiences, even their own, are terrible ways to learn anything. Our personal experiences are subject to every sort of cognitive error. We have preconceived expectations. We make mistakes and misinterpret things. We have biases.
Source: Brian Dunning, "Listener Feedback: Fads", Skeptoid, 5/26/2015
Check it out.
May 23rd, 2015 (Permalink)
In the Mail: The Philosophy of Argument and Audience Reception
The latest book by philosopher Christopher Tindale arrived today: The Philosophy of Argument and Audience Reception. Tindale has published a few previous books on argumentation, including one on fallacies and one on sophistry, each apparently from a point of view emphasizing rhetoric. These are all scholarly works and probably too advanced for the beginner, so if you're just starting out Tindale's textbook with Leo Groarke, Good Reasoning Matters, may be the place to start.
Source: Christopher W. Tindale, The Philosophy of Argument and Audience Reception, Cambridge University Press, 2015
May 20th, 2015 (Permalink)
So, what else is new?
Over the years, a number of readers have asked why there is no entry for the so-called "No-true-Scotsman Move" in The Fallacy Files. I've now at least partially remedied that oversight by adding it to the entry for Redefinition as a subfallacy of that fallacy. However, one important thing is missing from the entry, namely, a good real-life example. If anyone has such an example, please let me know.
Fallacy: The No-true-Scotsman Move
May 11th, 2015 (Permalink)
A Puzzle on the Menu
Check out today's menu at The Fallacy Files Cafe. The menu makes two emphatic statements: "Good food is not cheap!" and "Cheap food is not good!" Apparently, if you need to know the price of a dish before you order it, then you can't afford it.
Before proceeding, let's make a couple of things clear: the first statement doesn't mean that just some good food isn't cheap, but that all good food isn't. Moreover, when it says that good food isn't cheap it means that it's expensive. Similarly, the second means that all cheap food isn't good, that is, it's bad.
The puzzle is whether these statements mean the same thing, or something different. Don't just guess! How would you show that your answer is correct? When you think you know, click "Solution" below.
May 7th, 2015 (Permalink)
I've revised and extended the entry for the Quantifier-Shift Fallacy, replacing a cooked-up example with a real-life one. The new example is harder to understand than the previous one, but I think the fact that it comes from an actual argument made by a famous philosopher makes up for the additional difficulty. I've also added a technical appendix for those who know quantificational logic, or are interested in learning more about it.
May 2nd, 2015 (Permalink)
In the Email Bag
Lawrence Mayes writes:
Dr Henry Marsh, described as a brain or neurosurgeon, has made some frankly daft comments about cycle safety which have got into the press―probably only because they are daft.
Here's a quote from the good doctor that struck Lawrence as "daft"―see the Sources, below: "I see lots of people in bike accidents and these flimsy little helmets don’t help." Back to Lawrence:
There are two aspects to this story that should start alarm bells tinkling straight away. Firstly, we have someone giving an opinion outside his area of expertise and secondly it's all part of a book promotion.
He claimed that he has treated a number of patients involved in bike accidents whose helmets were "too flimsy" to provide any real protection. (I could also truthfully make that claim.) But what Dr Marsh misses is that regardless of the size of this sample it does not include those cyclists involved in accidents whose helmets protected them sufficiently so that they didn't require the intervention of a neurosurgeon nor would he have seen those cyclists who were not wearing helmets and were consequently dead.
This is an example of what's been called "the clinician's error"―see the Resource, below.
There is also the puzzling statistic coming from Bath University which appears twice in the Independent article; this is the reduction in berth that car drivers give cyclists wearing helmets, firstly as "around three inches" then a few paragraphs on as 8.5cm. The second time around it has had a bit of probabilistic decoration added: "In 2006 Dr Ian Walker…found that drivers were twice as like [sic] to get close to cyclists, an average of 8.5cm, when they were wearing a helmet" which, frankly I find incomprehensible (even if he meant "likely").
Whether the average distances are 2ft 9in and 3ft (or whatever the figures may be) seems, to me, to be largely irrelevant; the important figure is the relative accident figures for helmet wearers versus non-wearers.
Walker's study suggests that wearing a helmet may increase the risk of being hit by some unknown amount, but it can't justify changing one's behavior, since we don't know what the trade-off is between a greater risk of an accident and the protection of the head. Perhaps helmeted cyclists are somewhat more likely to be in an accident than unhelmeted ones, but less likely to be killed or seriously injured.
I draw two conclusions from this: firstly, brain surgeons are not as smart as popularly supposed and secondly you should wear a helmet, otherwise you could end up being treated by Dr Marsh.
In fairness, he's not a rocket scientist.
- Sarah Knapton, "Cycle helmets are useless, says brain surgeon", The Telegraph, 5/30/2014
- Antonia Molloy, "Cycle helmets don't provide protection, says neurosurgeon", The Independent, 5/31/2014
Resource: The Clinician's Error, 3/3/2005
The gambler's fallacy extends to the financial and investment markets. There is simply nothing like a fail proof investment or "get rich scheme" in the new trend of binary options. Although there are now serious binary option providers in Germany, such as BDSwiss which is EU regulated, prospective investors are cautioned to have realistic expectations to avoid the investor's fallacy.
The Gambler's fallacy spans international borders and technology, as Aussie players are now enjoying pokies on their mobiles according to this atn.com.au gaming page, which paints a surprising portrait of the Australian gaming market. The iPad in Australia in particular has become a mobile gambling station for one-armed bandit aficionados!
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