[...]Tunnel Resurfacing | hugeasscity[...]…

I give up and I’m out of urine.

“You haven’t conclusive proof that 1/2 of Seattle’s population is now (2010) less 40.” Nor would I need any. My intent was only to show that the statement “it is reasonable to extrapolate by those census numbers that 50% of the city is over the age of 40.” is false.

All women in Seattle could have had three children in the past decade, but your statement would still be incorrect. It simply is not a reasonable extrapolation.

I agree, that extrapolating data from two sets are more accurate than one, but still it does not conclusively prove your point. You are analysing only one snapshot or just one possibility using limited data. “Extrapolating from two points is surely more accurate than extrapolating from one,” can easily be wrong too. Look at it this way. If you are shooting at a target and you hit the target in two places that are very closely grouped but at the left edge of the target can you conclusively say you hit the bulls-eye? No. All you have is accuracy and not precision. Because you are basing your second shot on the first only lets you say something about the two sets of data but not much about expected outcome. It could be that if a third shot were taken it could hit at the bottom of the target (or the bulls eye or the top or in the original group). You can only say with your given data explained in your way proves one outcome. It does not speak for possibility. With limited data we can only talk about potential outcomes and not absolute ones. Thus your outcome isn’t much more right or wrong than mine. That’s all I am saying. You haven’t conclusive proof that 1/2 of Seattle’s population is now (2010) less 40. You can say, according to the average or mean it is likely to be less than 40.

So saying that I am “perfectly wrong” and “false” is incorrect because they are absolute statements without absolute, conclusive evidence. Sure the trends of two data sets can show that the average age is less than 40 but it isn’t an absolute result as your theory states. If take an even safer approach to your method we would round your numbers for average age(37) an mean age (35) to the nearest 10 years resulting in 40.

Let me put it another way. Since we only have two sets of data, we could looking at the top a spike in population. Or, we could be looking at turning the corner of a valley. We just don’t know. There is no conclusive date with out a third, forth, etc. sets of data. We both could be bogusly wrong too. Maybe every woman in Seattle had a baby December 31st 2009 or every parent over 60 moves in with their children? Those are possibilities that would really skew the data and that we do not know at this time. Sure they are radical possibilities and not very likely to occur, but until the next census happens they are possible outcomes too. All you can say with your results is this is the tendency of the two sets of two previous data sets.

Your point of view are rational and safe one but is far from conclusive. We do not have enough data to be conclusive about anything. We can only guess with what we know. Your absolute theory is an assumption (just as mine is). It is not based on enough information and uses only accuracy without proven precision to show your theory. Therefor you can not conclusively say I am “perfectly wrong” and making “false” statements. You can say my result is less likely to happen, and I’ll accept that, but so far you have not proven it false.

You do have a point, though. Westlake Park was gutted because the business community didn’t want to pay for it. Of course, that is the other theme. In general, we are notoriously cheap. The Kingdome was a great symbol for our cheap city. Our biggest, wildest park has a sewage plant in it. We had to expand the sewage plant (to comply with new rules) and could have built it somewhere else, but we were cheap. Same with voting against public transit. Likewise paying for the commons.

In the last ten years or so, things have begun to change. We’ve finally woken up to the fact that spending money sometimes makes sense. The monorail passed (three times) and only failed after an accounting error. Likewise, we’ve finally voted for rail. Park and housing levies usually win, while the school levies win so easily now that they aren’t even interesting.

All I’ve been trying to say since the beginning is that this statement of yours is false. It is not reasonable to extrapolate by those census numbers that 50% of the city is over the age of 40. One year’s survey data doesn’t at all indicate what the survey will look like a decade in the future.

//“The mean age in 1990 for Seattle was 35.
The mean age in 2000 for Seattle was 35.

The average age in 1990 for Seattle was 37.49.
The average age in 2000 for Seattle was 37.56.”

– Where does this come from?//

That was my own calculation. I broke out each survey by age using an average value for each age group. This gives me an apples-to-apples comparison. I then used these sets to calculate the mean and the average age. Looking at this data it is absolutely not “reasonable to extrapolate” that the average age is now over 40, which would be a requirement to make the statement “50% of the city is over the age of 40″ true.

//“Ah, so Seattle is aging. And at this rate the average age will be over 40 by… 2117.” — we both know that population growth is NOT linear.//

Sure. But extrapolating from two points is surely more accurate than extrapolating from one.

“Parameters: “it is reasonable to extrapolate by those census numbers that 50% of the city is over the age of 40.”” — what is this supposed to mean?

“The mean age in 1990 for Seattle was 35.
The mean age in 2000 for Seattle was 35.

The average age in 1990 for Seattle was 37.49.
The average age in 2000 for Seattle was 37.56.”

– Where does this come from?

“Ah, so Seattle is aging. And at this rate the average age will be over 40 by… 2117.” — we both know that population growth is NOT linear.

“Cities have a higher percentage of young professionals than the suburbs” — what sources are you getting this from?

“but I think [Tony]’s assumptions are far more reasonable.” — Why? because he agrees with you? He offered no evidence of how he came to that conclusion when I asked. Nor have you.

“I don’t think it’s reasonable to assume that our demographics have changed so much in a decade.” — See post 26

“But we don’t know if after the 30’s people move to the suburbs to raise children” — Never did I make any reason for why people move to and from the city nor would I ever use the census as evidence of a behavioral issue. Census quantify not qualify. You as an engineer should know that.

“we should have seen a huge spike in 35-44 year olds in 2000″ — but this is not entirely correct. According to both census there was a 12,000 person increase in the 25-44 year old population. The second largest growth in that ten year period. It is hard to say it “spiked” because we only have two census to draw from but, CERTIANLY, it did go up.

“and almost no 30-year olds” — What does this mean and how is it relevant? were there only five or six people in all of Seattle that were 30?

“Even assuming an even population distribution between 0 and 90 would get you 5.6% for that age range” — I gave you this argument at first but now it must be said that this is not a reasonable way to assume population distribution across the entire spectrum of age. As I stated above we both know population growth is not linear.

So, Matt, if yo could make a sensible argument with data, information and deduction then I would be open to changing my point of view. So far, you point to things but have no solid reasoning or evidence to back it up. Showing some stats

I take no offense at all to any of this but enjoy pushing you to act rather than react because you seem like a bright guy. You just don’t seem to put effort into your thoughts.

I didn’t mean to make this a pissing match, and certainly don’t mean to offend if I have. You just keep coming back, and there I am… just bored enough to type out one more response.

And, when you mean mean do you mean the arithmetic mean, the geometric mean or the harmonic mean? Would you mind showing your work for those mind bending calculations or should we just take your word for it?

Seriously, I am running out of pee for this pissing contest and am really beginning to think you are only arguing for sake of you ego. I see no point in in your sophomoric need to get in the last word. So I’ll do it for you…

Matt says, “last word”.