Stats Made Easy

Practical Tools for Effective Experimentation

Sunday, January 25, 2009

Decimal place makes all the difference

I presented a world-wide webinar Wednesday on "An Introduction to Mixture Design for Optimal Formulations" (posted with prior Stat-Ease webinars). As an ice breaker I described the view from my desk of downtown Minneapolis cloaked in a fog of frozen water crystals. One of the participants, our new value-added reseller Peter Trogos of Boston Software Group, expressed curiosity as to how Minnesotans can stand living in our Nation's icebox. It is hard to explain, but here's an example of what works for me -- embracing the elements.

I dressed up for a walk yesterday and my wife Karen got very alarmed. She misread our outdoor digital thermometer as -13 degrees, but I could see it was only -1.3 degrees. The placement of a decimal makes all the difference!

For my fortitude in walking no matter what the elements (like the proverbial postman) I was rewarded with this vista of the soccer field adjoining a nearby preschool. It was fun to think of upcoming days in Spring when it will be filled with energetic kids!

However, I enjoy the solitude of this frozen season, when only the conifers and hardy birds (and manic Minnesotans) remain active.

"It was January and cold in Minnesota, which was redundant."

-- Garrison Keillor as Guy Noir in the 1/24/09 radio broadcast of A Prairie Home Companion

Saturday, January 24, 2009

Paperwork reduction?

I've just completed my first year of high-deductible medical insurance coupled with a health savings account (HSA). I like this relatively new option very much. However, it requires yet another form to be submitted to the Internal Revenue Service (IRS 8889). I printed this out yesterday. It seemed complete, but then one last page spit out with only this paperwork reduction notice -- nothing else on either side. Have you ever felt like crying and laughing at the same time? Anyways, I feel better now after processing this piece of paper with the IRS paperwork reduction notice. You can see where I put stuff like this -- a machine that makes a very satisfactory grinding noise, which saves me gnashing my teeth.

Wednesday, January 14, 2009

Which of these is the winter weather outlier?

International (aka “Frostbite”) Falls reported a record low of 42 below Fahrenheit the other day. Would statisticians deem this an outlier? I think not – just another notch on the low end of the normal curve of temperature in this northern Minnesota city.

On the other hand, this morning I came across this pictured vehicle from Florida. That is much more unusual in the dead of Minnesota winter. You may not resolve the license plate in the photo, but here are a couple of clues that the driver is not a Minnesotan:
-- They did not brush off the snow from the rear window – only ran the wipers.
-- They are tailgating on the exit ramp to Interstate 694 on a day of extreme cold when black ice* makes the roads extremely slippery.

Given these unsafe practices, I predict that this outlying Floridian car will soon be off the roads and we will be back to our normal distribution of Minnesotan and Wisconsites (don't get me going on them!).

PS. Here’s a little poem that just came through in an email circulating around these parts (author unknown):

The weather here is wonderful
So I guess I'll hang around
I could never leave Minnesota
'Cause I'm frozen to the ground!

*If you do not know about black ice, consider yourself fortunate. It’s a phenomenon that occurs only in below-zero cold: The water resulting from the internal combustion engine freezes when the exhaust hits the road. This ice cannot be seen – hence the designation of it being “black.”

Sunday, January 11, 2009

The MAD statistics for overkill

Over Christmas vacation I took a tour of the Titan Missile Museum south of Tucson. There, seeing this moth-balled intercontinental ballistic missile (ICBM) under glass, visitors like me can relive the days when it seemed that nuclear Armageddon could occur at any time. I remember practicing duck and cover drills in grade school during the Cuban Missile Crisis. The exhibit I found most interesting from a statistical standpoint was a detailing of how many missiles the US military planned to launch in order to fulfill the doctrine of mutually assured destruction (MAD). They called this “overkill.”

“The reliability of the first 2 ICBM’s, Atlas and Titan, were so low the military determined they would need at least 4 ICBM’s to hit one target with the assumption of only a 70 percent chance of target strike success.”
-- Len Losik (MilsatMagazine “Military Satellites and Rockets—No More Failures!")

This MAD overkill boggles my mind by its macabre calculations of deathly probabilities.

PS. In my research I came across these intriguing just-published memoirs by General Glenn Kent and his “Thinking About America’s Defense” (made available as a public service by the RAND Corporation).

Tuesday, January 06, 2009

Number smiths gain top three spots for having the best occupations

Today’s Wall Street Journal article on Doing Math to Find the Good Jobs reports that the top three professions are mathematician, actuary and statistician! The perpetrator of this outrageous claim is Les Krantz, author of the “Jobs Rated Almanac.” You can infer what floats his boat by comparing these three ivory tower jobs to the down and dirty ones he rated as the absolute worst: lumberjack, dairy farmer and taxi driver.

So it seems that this caps the revenge of the nerds. However, I am not sure what to conclude from a school chum who went on to become an actuary, made a mint in investments on the side and then retired early to become a dairy farmer. I suspect that many math mavens secretly desire being outdoors chopping trees rather than crunching numbers in an office.

Nevertheless, maybe it’s best for those of us that can do the calculations to resist acting upon our daydreaming during the deadly dull parts. For example, when I rev up my little chain saw things often get quickly out of control, such as the time I took it up a ladder to cut off a branch and while leaning at a particularly dangerous angle got stung viciously by a wickedly large wasp. At times like this one must be thankful for a job involving numbers that can be done despite being temporarily incapacitated.