Confounding Factor

2009-12-02T01:57:00.000-08:00

Milo left this comment...

Depends on your point of view. From the tree's fixed position point of view, both are going round the tree; neither is going round the other. From the squirrel's point of view -- always facing toward the center of the tree as he moves around the tree-- the man is always straight staight-ahead: straight through the tree and is not moving around the squirrel. From the squirrel's point of view -- always facing in same direction as he moves around the tree, the man is going round the squirrel.

PS. Your definition of confounding seems a bit off. Unless a confounder is associated with at least two elements in an association, it can't influence the association.

Here is my response to Milo's comments...

Milo - I am amazed someone is actually reads this blog besides myself. Your answer to my challenge is definitely well thought out and makes it seem like I thought of a very clever questions. The last part of your answer concluding that the man is going around the squirrel because the squirrel is always facing the same direction - well, I must confess that answer confounds even my mind, and that is hard to do. So thus I must give you credit for answing this correcly because I am unable to devise a logical response to counteract it.

Now about my defition of confounding - I think you are just trying to give me a hard time with that one. I see no reason why there would need to be more than one other factor besides the confounder in an association in order for the counfounder to influence the association.

For exammple, take the relationship between shoe size and mathematic ability in students Grades K-8 in a school where all the students are given the same test. We would find that is a very high correlation between shoe size and test scores. But in fact the shoe size has no effect on the test scores, it is confounded by age. We would find that if we took only kids the same age and then correlated their shoe sizes with their test scores, no correlation would be found - identifying the confound of shoe size with age in influencing test scores. So here all you need is the one other factor, age, the true factor associated with test scores, to exist in order for there to be a confounding factor shoe size, a false association with test scores.

Howdy

2009-11-04T23:25:00.000-08:00

Very Interesting...

2009-10-23T03:37:00.001-07:00

Man pleads guilty to DWI in motorized La-Z-Boy

AP – A motorized La-Z-Boy chair driven by Dennis Anderson of Proctor was operating when he hit a parked vehicle … Thu Oct 22, 9:17 pm ET

DULUTH, Minn. – A Minnesota man has pleaded guilty to driving his motorized La-Z-Boy chair while drunk. A criminal complaint says 62-year-old Dennis LeRoy Anderson told police he left a bar in the northern Minnesota town of Proctor on his chair after drinking eight or nine beers.

Prosecutors say Anderson's blood alcohol content was 0.29, more than three times the legal limit, when he crashed into a parked vehicle in August 2008. He was not seriously injured.

Police said the chair was powered by a converted lawnmower and had a stereo and cup holders.

Sixth Judicial District Judge Heather Sweetland stayed 180 days of jail time Monday and ordered two years of probation for Anderson. His attorney, David Keegan, did not immediately return a call for comment.

___

Information from: Duluth News Tribune, http://www.duluthsuperior.com

Where Was I In '86? Where Were You?

2009-08-24T00:43:00.000-07:00

I changed my look a little in '86. What do you think?

'84 Rocks! Where Were You?

2009-07-28T01:49:00.000-07:00

The Confounding Factor Challenge

2009-07-26T01:43:00.000-07:00

A man is walking around a tree. A squirrel is climbing around the trunk of the tree, and is always on the opposite side of the man. Is the man walking around the squirrel?

Feel free to leave your solution in the comment area.

I warn you though, I'm pretty clever so do not feel bad when you find out your answer is wrong. Oh, and the owner of the blog is always right. It is a unspoken blog rule. I am just jesting. I do not know the answer but I am going to ponder the riddle and post my solution in a few days.

Just a reminder

2009-07-10T03:43:00.000-07:00

You don't have to

like me to

cool!

Honest...

My 4th Of July Poem

2009-07-04T23:35:00.000-07:00

Hip hip horray

Today's the day

Today's a day to play!

Happy 4th of July!!!

Yes, I've Always Been This Cute

2009-07-02T03:27:00.000-07:00

See...You didn't believe me did you? I never lie.

What More Can I Add To This?

2009-04-14T18:41:00.000-07:00

Hopping Along

2009-04-12T23:15:00.000-07:00

A Little B-Ball

2009-04-11T22:55:00.000-07:00

Counfounding Factors in Baseball

2009-04-10T10:29:00.000-07:00

Yesterday my oldest son Grant had his first baseball game. He did a great job and was fun to watch and gave me a nice excuse to spend some time outside doing nothing on a nice spring day.

In keeping with the theme here - there are many confounds in baseball. One I thought of was the relationship between leaving men on base and winning the game. In browsing the MLB boxscores from yesterday, in 5 of the 7 games, the team that left the most runners on base without scoring won the game. But - that's generally not a good thing, so why would that be related to wining the game? Here the real factor is hits as 4 or those 5 games the wining team also had more hits, and it makes sense that the more hits you get the more likely you will win, and as a side effect will also likely leave more runners on base, but leaving runners on base does not make you win the game. But - next time your team leaves the bases loaded don't feel so bad they will likely win the game anyway (unless its the Cubs in the playoffs - there are factors at work there that defy all sound theories)

Using Confounds As a Last Resort to Help Our Case

2009-04-09T11:15:00.000-07:00

Properly understanding confounding factors can help us understand things better. And sometimes, we can make up or exaggerate the presence of certain counfounding factors to help our case. However, unless we have data to back up out claims, this isn't often successful. For example, I could never quite convince my Statistics professors to better my grades, even I when tried to make the case that my poor study habits and arithmetic errors were counfounding my abilty to demonstrate my grasp of the material, which I really thought was quite good.

The Confound of Genetic Factors in Using Height as a predictor of Age

2009-04-09T11:05:00.000-07:00

Once I understood this common confound - it helped me growing up - as I was short for my age.

Welcome

2009-04-08T12:59:00.000-07:00

"Dad, a confounding factor has prohibited me from cleaning my room today"

"Hmm. I see. What confounding factor was it?"

"The wind was blowing from the East."