The Risk of Misunderstanding Risk

20 Mar

Women who participate in breast cancer screening from 50 to 69 live on average 12 more days. This is the best case scenario. Gerd has more such compelling numbers in his book, Calculated Risks. Gerd shares such numbers to launch a front on assault on the misunderstanding of risk. His key point is:

“Overcoming innumeracy is like completing a three-step program to statistical literacy. The first step is to defeat the illusion of certainty. The second step is to learn about the actual risks of relevant eventsand actions. The third step is to communicate the risks in an understandable way and to draw inferences without falling prey to clouded thinking.”

Gerd’s key contributions are on the third point. Gerd identifies three problems with risk communication:

  1. using relative risk than Numbers Needed to Treat (NNT) or absolute risk,
  2. Using single-event probabilities, and
  3. Using conditional probabilities than ‘natural frequencies.’

Gerd doesn’t explain what he means by natural frequencies in the book but some of his other work does. Here’s a clarifying example that illustrates how the same information can be given in two different ways, the second of which is in the form of natural frequencies:

“The probability that a woman of age 40 has breast cancer is about 1 percent. If she has breast cancer, the probability that she tests positive on a screening mammogram is 90 percent. If she does not have breast cancer, the probability that she nevertheless tests positive is 9 percent. What are the chances that a woman who tests positive actually has breast cancer?”

vs.

“Think of 100 women. One has breast cancer, and she will probably test positive. Of the 99 who do not have breast cancer, 9 will also test positive. Thus, a total of 10 women will test positive. How many of those who test positive actually have breast cancer?”

For those in a hurry, here are my notes on the book.

Disgusting

7 Feb

Vegetarians turn at the thought of eating the meat of a cow that has died from a heart attack. The disgust that vegetarians experience is not principled. Nor is the greater opposition to homosexuality that people espouse when they are exposed to foul smell. Haidt uses similar such provocative examples to expose chinks in how we think about what is moral and what is not.

Knowing that what we find disgusting may not always be “disgusting,” that our moral reasoning can be flawed, is a superpower. Because thinking that you are in the right makes you self-righteous. It makes you think that you know all the facts, that you are somehow better. Often, we are not. If we stop conflating disgust with being in the right or indeed, with being right, we shall all get along a lot better.

The Best We Can Do is Responsibly Answer the Questions that Life Asks of Us

5 Feb

Faced with mass murder, it is hard to escape the conclusion that life has no meaning. For how could it be that life has meaning when lives matter so little? As a German Jew in a concentration camp, Victor Frankl had to confront that question.

In Man’s Search for Meaning, Frankl gives two answers to the question. His first answer is a reflexive rejection of the meaninglessness of life. Frankl claims that life is “unconditional[ly] meaningful.” There is something to that, but not enough to hang on to for too long. It is also not his big point.

Instead, Frankl has a more nuanced point: “If there is … meaning in life …, then there must be … meaning in suffering.” (Because suffering is an inescapable part of life.) The meaning of suffering, according to him, lies in how we respond to it. Do we suffer with dignity? Or do we let suffering degrade us? The broader, deeper point that underpins the claim is that we cannot always choose our conditions, but we can choose the “stand [we take] toward the conditions.” And life’s meaning is stored in the stand we take, in how we respond to the questions that “life asks of us.”

Not only that, the extent of human achievement is: responsibly answering the questions that life asks of us. This means two things. First, that questions about human achievement can only be answered within the context of one’s life. And second, in responsibly answering questions that life asks of us, we attain what humans can ever attain. In a limited life, circumscribed by unavoidable suffering, for instance, the peak of human achievement is keeping dignity. If your life offers you more, then, by all means, do more—derive meaning from action, from beauty, and from love. But also take solace in the fact that we can achieve the greatest heights a human can achieve in how we respond to unavoidable suffering.

Ruined by Google

13 Jan

Information on tap is a boon. But if it means that the only thing we will end up knowing—have in your heads—is where to go to find the information, it may also be a bane.

Accessible stored cognitions are vital. They allow us to verify and contextualize new information. If we need to look things up, because of laziness or forgetfulness, we will end up accepting some false statements, which we would have easily refuted had we had the relevant information in our memory, or we will fail to contextualize some statements appropriately.

Information on tap also produces another malaise. It changes the topography of what we know. As search costs go down, people move from learning about a topic systematically to narrowly searching for whatever they need to know, now. And knowledge built on narrow searches looks like Swiss cheese.

Worse, many a time when people find the narrow thing they are looking for, they think that that is all there to know. For instance, in Computer Science and Machine Learning, people can increasingly execute sophisticated things without knowing much. (And that is a mostly a good thing.) But getting something to work—by copying the code from StackOverflow—gives people the sense that they “know.” And when we think we know, we also know that there is not much more to know. Thus, information on tap reduces the horizons of our knowledge about our ignorance.

In becoming better at fulfilling our narrower needs, lower search costs may be killing expertise. And that is mostly a bad thing.

The Other Side

23 Oct

Samantha Laine Perfas of the Christian Science Monitor interviewed me about the gap between perceptions and reality for her podcast ‘perception gaps’ over a month ago. You can listen to the episode here (Episode 2).

The Monitor has also made the transcript of the podcast available here. Some excerpts:

“Differences need not be, and we don’t expect them to be, reasons why people dislike each other. We are all different from each other, right. …. Each person is unique, but we somehow seem to make a big fuss about certain differences and make less of a fuss about certain other differences.”

One way to fix it:

If you know so little and assume so much, … the answer is [to] simply stop doing that. Learn a little bit, assume a little less, and see where the conversation goes.

The interview is based on the following research:

  1. Partisan Composition (pdf) and Measuring Shares of Partisan Composition (pdf)
  2. Affect Not Ideology (pdf)
  3. Coming to Dislike (pdf)
  4. All in the Eye of the Beholder (pdf)

Related blog posts and think pieces:

  1. Party Time
  2. Pride and Prejudice
  3. Loss of Confidence
  4. How to read Ahler and Sood

Loss of Confidence

21 Oct

We all overestimate how much we know. If the aphorism, “the more you know, the more you know that you don’t know” is true, then how else could it be? But knowing more is not the only path to learning about our ignorance. Mistakes are another. When we make mistakes, we get to adjust our parameters (understanding) about how much we know. Overconfident people, however, incur smaller losses when they make mistakes. They don’t learn as much from mistakes because they externalize the source of errors or don’t acknowledge the mistakes, believing it is you who is wrong, not them. So, the most ignorant (the most confident) very likely make the least progress in learning about their ignorance when they make mistakes. (Ignorance is just one source of why people overestimate how much they know. There are many other factors, including personality.) But if you know this, you can fix it.

Pride and Prejudice

14 Jul

It is ‘so obvious’ that policy A >> policy B that only who don’t want to know or who want inferior things would support policy B. Does this conversation remind you of any that you have had? We don’t just have such conversations about policies. We also have them about people. Way too often, we are being too harsh.

We overestimate how much we know. We ‘know know’ that we are right, we ‘know’ that there isn’t enough information in the world that will make us switch to policy B. Often, the arrogance of this belief is lost on us. As Kahneman puts it, we are ‘ignorant of our own ignorance.’ How could it be anything else? Remember the aphorism, “the more you know, the more you know you don’t know”? The aphorism may not be true but it gets the broad point right. The ignorant are overconfident. And we are ignorant. The human condition is such that it doesn’t leave much room for being anything else (see the top of this page).

Here’s one way to judge your ignorance (see here for some other ideas). Start by recounting what you know. Sit in front of a computer and type it up. Go for it. And then add a sentence about how do you know. Do you recall reading any detailed information about this person or issue? From where? Would you have bought a car if you had that much information about a car?

We not just overestimate what we know, we also underestimate what other people know. Anybody with different opinions must know less than I. It couldn’t be that they know more, could it?

Both, being overconfident about what we know and underestimating what other people know leads to the same thing: being too confident about the rightness of our cause and mistaking our prejudices for obvious truths.

George Carlin got it right. “Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?” It seems the way we judge drivers is how we judge everything else. Anyone who knows less than you is either being willfully obtuse or an idiot. And those who know more than you just look like ‘maniacs.’

Firmly Against Posing Firmly

31 May

“What is crucial for you as the writer is to express your opinion firmly,” writes William Zinsser in “On Writing Well: An Informal Guide to Writing Nonfiction.” To emphasize the point, Bill repeats the point at the end of the paragraph, ending with, “Take your stand with conviction.”

This advice is not for all writers—Bill particularly wants editorial writers to write with a clear point of view.

When Bill was an editorial writer for the New York Herald Tribune, he attended a daily editorial meeting to “discuss what editorials … to write for the next day and what position …[to] take.” Bill recollects,

“Frequently [they] weren’t quite sure, especially the writer who was an expert on Latin America.

“What about that coup in Uruguay?” the editor would ask. “It could represent progress for the economy,” the writer would reply, “or then again it might destabilize the whole political situation. I suppose I could mention the possible benefits and then—”

The editor would admonish such uncertainty with a curt “let’s not go peeing down both legs.”

Bill approves of taking a side. He likes what the editor is saying if not the language. He calls it the best advice he has received on writing columns. I don’t. Certainty should only come from one source: conviction born from thoughtful consideration of facts and arguments. Don’t feign certainty. Don’t discuss concerns in a perfunctory manner. And don’t discuss concerns at the end.

Surprisingly, Bill agrees with the last bit about not discussing concerns in a perfunctory manner at the end. But for a different reason. He thinks that “last-minute evasions and escapes [cancel strength].”

Don’t be a mug. If there are serious concerns, don’t wait until the end to note them. Note them as they come up.

“Cosal” Inference

27 Apr

We often make causal claims based on fallible heuristics. Some of the heuristics that we commonly use to make causal claims are:

  1. Selecting on the dependent variable. How often have you seen a magazine article with a title like “Five Habits of Successful People”? The implicit message in such articles is that if you were to develop these habits, you would be successful too. The articles never discuss how many unsuccessful people have the same habits or all the other dimensions on which successful and unsuccessful people differ.
  2. Believing that correlation implies causation. A common example goes like this: children who watch more television are more violent. From this data, people deduce that watching television causes children to be violent. It is possible, but there are other potential explanations.
  3. Believing that events that happen in a sequence are causally related. B follows A so A must cause B. Often there isn’t just one A, but lots of As. And the B doesn’t instantaneously follow A.

Beyond this, people also tend to interpret vague claims such as X causes Y as X causes large changes in Y. (There is likely some motivated aspect to how this interpretation happens.)

Bad Hombres: Bad People on the Other Side

8 Dec

Why do many people think that people on the other side are not well motivated? It could be because they think that the other side is less moral than them. And since opprobrium toward the morally defective is the bedrock of society, thinking that the people in the other group are less moral naturally leads people to censure the other group.

But it can’t be that two groups simultaneously have better morals than the other. It can only be that people in the groups think they are better. This much logic dictates. So, there has to be a self-serving aspect to moral standards. And this is what often leads people to think that the other side is less moral. Accepting this is not the same as accepting moral relativism. For even if we accept that some things are objectively more moral—not being sexist or racist say—some groups—those that espouse that a certain sex is superior or certain races are better—will still think that they are better.

But how do people come to know of other people’s morals? Some people infer morals from political aims. And that is a perfectly reasonable thing to do as political aims reflect what we value. For instance, a Republican who values ‘life’ may think that Democrats are morally inferior because they support the right to abortion. But the inference is fraught with error. As matters stand, Democrats would also like women to not go through the painful decision of aborting a fetus. They just want there to be an easy and safe way for women should they need to.

Sometimes people infer morals from policies. But support for different policies can stem from having different information or beliefs about causal claims. For instance, Democrats may support a carbon tax because they believe (correctly) the world is warming and because they think that the carbon tax is what will help reduce global warming the best and protect American interests. Republicans may dispute any part of that chain of logic. The point isn’t what is being disputed per se, but what people will infer about others if they just had information about the policies they support. Hanlon’s razor is often a good rule.