WSJ: Numbers Guy

The Numbers Guy examines numbers in the news, business and politics. Some numbers are flat-out wrong or biased, while others are valid and help us make informed decisions. Carl Bialik tells the stories behind the stats, in daily updates on this blog and in his column published every other Friday in The Wall Street Journal. Carl, who holds a degree in mathematics and physics from Yale University, also cowrites The Daily Fix, a sports column on WSJ.com. He welcomes your comments at .

WSJ: The Numbers
The Numbers
copyright © 2016 Dow Jones & Company, Inc.
The Wall Street Journal examines the way numbers are used, and abused.

Behind The Numbers: Polling Debate
Opinion polls based on probability samples have accurately reflected public sentiment for decades. But declining response rates and the time and expense required to collect the data has spurred interest in a fast and cheap alternative: online polls, which typically rely on nonprobability samples.
Numbers in the News: 361
The number of possible opening moves in Go is 361. In chess, the possible opening moves is 20 (4 knight moves and 16 pawn moves). That disparity grows as the games advance and points up a breakthrough in artificial intelligence.
Behind The Numbers: How to Calculate Odds
​Figuring out the odds of winning the Powerball lottery draws upon a vein of applied mathematics known combinatorics, which deals with ways of arranging and distributing objects.
Numbers in the News: Powerball
Rather than repeating the same spiel on the Powerball, we figured we could point you to some of the writings we've read on lottery fever.
Behind the Numbers: Saudi Aramco Valuation
The potential sale of shares in Saudi Arabia's state owned oil giant raises the question of how valuable the company would be, with estimates of market valuations ranging into the trillions of dollars. Here's a look at Saudi Aramco by the numbers.
Behind The Numbers: An Upset VW Owner
When German auto maker Volkswagen admitted to installing software in some of its diesel cars to cheat on emissions tests, Hendrik Wolff, an environmental economist who moved to the U.S. in 2003, took it personally.
Numbers in the News: -1.6%, -1.7%
After a rout in overseas markets lifted the curtain on the U.S. trading day, investors sent the Dow Jones Industrial Average down 1.6%, the biggest year-opening loss since 2008. But it may not mean much. And New York City announced that major crimes fell 1.7% to a new low last year. But the devil is in the details.
Happy New Year, With a Leap
Happy New Year, Numbers fans, may it be filled with health, prosperity and peace. If nothing else, at least we've survived the perils of New Year's Day and we've got an extra day to work on our goals this year.
Behind The Numbers: Going Viral
​Microbes living in and on the human body outnumber human cells 10 to 1. The microscopic bacteria inhabit the surface of the skin, nestle deep in i​t​s layers, and swim in our saliva.​ ​But the largest number colonize our gut.
Behind The Numbers: The Importance of ‘Check Digits’
Credit-card numbers, International Standard Book Numbers, bank routing numbers, Universal Product Codes, Cusip numbers used to identify financial instruments, plus many other items all include a calculated “check digit” that allows the numbers to be automatically validated by a computer.