Marking the Winner Board.

A surprised test subject.

Here are some graphs of the breathalyzer results from that night. The green bar graph above shows the combined BAC guesses from everyone tested. Eleven people guessed they were at a .08, just at the fringe of being too drunk to drive. It was the most popular answer, second only to guessing 0.12. The average guess was 0.098.

Another interesting result was that almost no one guessed their own BAC to be .20 or higher.

This blue graph above illustrates the actual level of drunkenness of my St. Patrick's Day drinking crowd. Most people were above the limit for driving. I should mention here that most people were not planning on driving.

The most popular level of drunkenness (mode) was 0.15, but the average (mean) was 0.107.

These behaviors were not reliable indicators that a pedestrian was drunk:

1. Holding the breathalyzer with two hands.
2. Inhaling through the breathalzyer.
3. Behaving as if their future depended on the results of this test.
4. Imploring their group to leave and go DANCING!

The drinks chart above shows the blood alcohol levels we tested from 8pm til midnight, as well as what the subjects had been drinking. Although both tipsy and drunk people are represented within every hour, the BACs trended upward as the night went on. Jameson Whiskey must have been on sale nearby as a tribute to St. Patricks Day.

We had a blast. I wish I'd collected more data!

Maybe next time I'll be the one guessing their Blood Alcohol Content.

Suzi and I. We were set up in front of Sacramento's Comedy Spot.

Interacting with the inebriated public has a bad reputation. I found it to be hilarious.

Here is a chart showing the poor quality of the guesses collected that night.

From left to right, I've plotted the test subjects' actual BAC. The vertical axis indicates the scale of their guessing error.

This chart is repeated below, with a few more notes:

People were very likely to be wrong about their blood alcohol level.

I understand that alcohol breath and blood testing is important, but this is terrible. People suck at this.

Can you imagine if the driving speed laws were like this? What if you didn't have a speedometer in your car, and you'd never even seen one being used. What if the speed limit was 6,000 feet/minute? How would you know what that was like? Could you trust the other people on the road to know? Would you constantly recalculate your position and the time which had passed since your departure?

This was a great night, we had a great time and gathered some great information.

People love checking their blood alcohol level, especially when it doesn't cost $10,000.

Back to page one.