• Frank
• Jul 16,2008
• In: 2008 US Elections, News

Lies, damn lies and statistics

The New York Times has conducted a poll (hat tip: Democracy in America) on race in America. Its results? According to the accompanying article,

Americans’ perceptions of the fall presidential election between Mr. Obama, Democrat of Illinois, and Senator John McCain, Republican of Arizona, also underlined the racial discord that the poll found. More than 80 percent of black voters said they had a favorable opinion of Mr. Obama; about 30 percent of white voters said they had a favorable opinion of him.

Take a close look at the graphic, though:

(According to the article, the 95% margin of error on this poll was plus or minus three percentage points for whites, and six points for blacks. By my own calculations, the 99% margin of error was plus or minus four points for whites, and seven points for blacks.)

All this really shows is that McCain and Obama are in what is essentially a statistical dead heat among whites (if they really are tied, the probability of getting a poll result this extreme or more extreme is 3%, which I don’t consider statistically significant) and Obama is winning by a huge margin among blacks (if they really are tied, the probability is 7 x 10^-82, or roughly the probability of my computer spontaneously blowing up at exactly 2:01 PM today).

Thus, the headline “Poll Finds Obama’s Run Isn’t Closing Divide on Race” is woefully inappropriate, writes Democracy in America,

Yet “Whites Approve Both Candidates Equally; Blacks Enthusiastic for Obama”, while the correct headline, would not do what the Times wants us to do, which is gnash our teeth for the state of divided America.