Pretending to use decision theory and rational thought for solve everyday problems is likely a conceit. The most common way of making serious decisions is to resort to authority. Why is this? After all, the greatest technical advances in human culture have all taken place …continue reading

## Decisions Based on Test Results?

The decisions you make are important, but maybe not as important as the ones made for you by other people (following Mitt, we confer people status on corporations). If a pharmaceutical company decides to market a new drug and the new, and expensive, drug supposedly …continue reading

## Decision Theory – Who Cares?

I lost track of how many things I have posted — even loosely — about decision theory, but it is a lot. And we always come back to the same thing — so what? Assume you were highly trained to automatically apply rational thinking and …continue reading

## The Flaws of Modern “Thinking”

While waiting for my muse to deliver an idea for a post involving decision theory, I opened Facebook, something I only do every other week or so, and found that my son, a solar physicist, had posted the following grouse (his nomenclature). With his permission …continue reading

## Good Logic: Bad Premise

If real life decision making could be as obvious as is typical in logic puzzles, the world would probably be a better place. The truth is that most decisions we make can be based on good logic, but start from bad initial assumptions — and …continue reading

## Mathematics: Invented or Discovered? Well, It Depends…

We are unlikely to add much new to the discussion of why math works, but by exploring the issues, we might learn more about the question. For instance, Barry Etheridge pointed out that in some sense “No triangle exists out here” by the traditional definition …continue reading

## Why Does Math Work?

The August 2011 issue of *Scientific American* has an interesting article by Mario Livio called “Why Math Works.” The issue he addresses applies also to the underpinnings of logic and decision theory. The puzzle starts with the observation that in the real world of sensory …continue reading

## Data, Randomness, and (More) Noise

My recent post concerning randomness elicited more than the usual number of comments, so perhaps we could profitably consider some more features of data, randomness, and noise.

We usually think of data as some collection (bytes in the case of computers) that contains useful …continue reading

## What is Random?

Today’s post is not the usual puzzle/decision theory short note. It is related to the normal subject, but in a way that will take some explaining. The inspiration came when I downloaded and installed an update to the VLC player. As with many applications, the …continue reading

## Critical Thought: Examples

Part of my reason for posting about decision theory is to encourage people to realize that critical thinking is part of their everyday life and not some artsy theoretical musing. The need for such awakening came home to me again today when I read the …continue reading

## Human or Computer?

Since this post is about decisions, consider how you decide if your online chatting partner is a human or robot. This is the essence of the famous Turing test proposed by Alan Turing to decide if a computer has achieved intelligence. The test is …continue reading

## To Sue or Not to Sue?

I serve on the Board of a homeowners association, and we are preparing to vote on whether to sue a contractor or not. The details of our complaint are not important. The process of deciding what to do is very important.

Many contracts have mandatory …continue reading

## Is the End Near?

Since I am writing this and you are reading it, the world seems to still exist in spite of recent claims that the end was here. When you saw the billboards announcing the end of the world, did you decide it was true? Probably not, …continue reading

## Marilyn’s Coins

The last several postings to this site have involved the huge changes in probabilities that arise when events are coupled in non-obvious ways. The examples included a three-dice gambling game and the collapse of the world-wide economic system. These puzzles are not pie-in-the-sky …continue reading

## Why the Economy Failed – the Three Dice Game

Recently I posted articles about gambling on a three-dice throw and whether children are boys or girls. The point was to emphasize that making good decisions requires knowing which events are correlated. This is most obvious in the fights that still occasionally erupt over the …continue reading

## Dice Games and Children Solved

In my previous post, we considered the three-dice game where you bet a dollar on a number coming up. You get your money back plus a dollar for each time your number comes up. If your number does not come up, then you lose. …continue reading

## Dice Games and Children

Enough of ruminations about ideal tax cheats. When learned papers are written trying to explain why people comply with the tax code, who am I to try to explain it meaningfully in 500 words or less? If you want to delve deeper into the issue, …continue reading

## More Ideal Tax Cheats

In my previous post about ideal tax cheats, we considered the puzzle of why there is such a high compliance rate for paying taxes when a purely business (i.e. logical) analysis indicates that one can maximize lifetime income by paying less tax than what …continue reading

## Ideal Tax Evasion

We often pose decision making problems in either the real world or a logical world to exercise our minds in making logically correct decisions. But what about normal decisions that we all make? Consider the decision to pay taxes. The situation is described in the …continue reading

## Will This Destroy the Earth? Can I Get a Picture?

This blog is primarily about how to make decisions. Some of those decisions involve solving puzzles. This is good for practice, but what about real, physical problems? In the news we see almost hysterical covering on the nuclear danger in Japan. Some people, particularly in …continue reading

## Decisions and Venus’ Orbit

At first reading, the last two posts to this blog might seem to be out of character. The blog’s title indicates items involving decision theory will be discussed, but the latest postings dealt with various issues of the solar system. In particular, I discussed to …continue reading

## Venus Decoded

In a recent post, I mentioned that the planet Venus executes some spectacular motions compared to the other planets as seen from Earth. We can be amazed and appreciate these aspects, but try to think what this meant to the ancients. They did not think …continue reading

## Some Answers to Previous Puzzles

In the last post, I presented some practical puzzles. That is, practical a few thousand years ago — mostly for fun now.

The first was to determine the cardinal compass points to within a degree or so with no tool more complicated than a stick. …continue reading

## How Long is a Year?

Two types of puzzles are particularly attractive: (1) puzzles with both a lengthy hard-to-work-out solution and an “Aha” solution in which a sudden insight gives you a simple solution; and (2) practical puzzles with application in the natural world.

Many of these enchanting types of …continue reading

## More Proofiness

In the last post, I discussed a new book, by Charles Seife, **Proofiness**. Since it must go back to the library tomorrow (I tried to renew, but someone put a hold on it — a reader?), I have to hurry to share another fascinating …continue reading

## Proofiness and Lies

Part of the reason I am interested in decision theory and puzzles is that so many decisions in life are made irrationally and sub-optimally, while many puzzles go unsolved. Anyone who spends any time considering the ease with which people can be confused by numbers …continue reading

## What is a Liar? Does It Matter?

Constructing puzzles and decision theory problems is easy if you define an artificial world. For instance, the classic case of the truth-tellers and liars who live on an island. A castaway wants to get to the village on the island for food and help. He …continue reading

## Mistaking the Solution for the Problem

Sometimes we jump into an application of decision theory prematurely. Problems like deciding the probability that a person has AIDS given a positive result on a clinical test are easy to set up and solve. In essence, both the problem and nature of the solution …continue reading

## Why Does January 1 Mark a New Year?

A friend mused about why the new year comes on January 1. This is part of my response.

Happy New Year! But why January first? Because the orbital periods of the Earth and moon not even multiples. And a year is not an integral number …continue reading

## Quantum Twenty Questions and You

Here is a simple game that might illustrate some of the quirks of quantum mechanics — or at least might stimulate some thought.

The first is a variant of twenty questions. I believe it was invented by the physicist Wheeler (try searching on Wheeler’s twenty …continue reading