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It's not just government and journalists, plenty of corporations make pie in the sky predictions that turn out to be wrong. How many mergers have we been told will enhance shareholder value that turn out to be busts? E.g., Dalmier-Chrysler, Qwest-US WEST, AOL-Time Warner, HP-Compaq, etc......

Corporations should be free to make business decisions with their own money. This is moral. (it helps contain the risk to the people that bet their money)

Bureaucrats should not be free to make business decisions with other peoples' money. This is immoral. (the risk spreads to people that had nothing to do with and were even opposed to the decision)

Westgate is not struggling to pay its debt. It is NOT paying its debt. Is this the kind of precision you are asking for from others? It doesn't matter whether you are doing this out of the goodness of your heart and newspapers are doing it as a business. In the context of a post in which you make a legitimate claim that the papers use imprecise inputs to derive a precise output, how can you use a subjective adverb like "struggling" when the demonstrable truth is that they are not paying their debts, are in default, and the City of Glendale is on the hook. Seems like unnecessary temporizing on your part. But then, you are not making as much money as the newspapers on this project, so I guess our standards should be set lower for you.

“This is obviously wrong because we don't have enough information on the two factors--size and price--to do any more than make a rough calculation of price per acre. The best the author can do is say the price is ‘about $15,000 an acre.’”
The first sentence is true. But we don’t have enough information to know if the second one is true or not. The author may have had all the required information to conclude that the price was $15,433/acre but, for what ever reason, did not include it all in the article.

Jack – Re-read the post – He wrote that Glendale is struggling, not Westgate.

mahtso - Jack isn't paid to comment on Greg's posts, so your standards should be set lower for him.

All those digits look impressive, but I call this the illusion of precision. In chem lab, we learned about significant digits. 948 has three significant figures, as does 0.948. When multiplying, dividing, adding, or subtracting two numbers, the answer can't have any more significant digits than the number with the least significant digits, no matter what the calculator says.

In the example above, "about $9.8 million" arguably has two significant digits and about 635 has at most three significant digits. So if we divide $9.8 million by 635 acres, the answer is about $15,000 per acres, just as Greg said.

I am hedging a bit, because about $9.8 million could mean that we know it is between $9.75 and $9.85 million or it could be more of a guesstimate, in which case we should use $10 million in the numerator, which only has one significant digit.

In the days before calculators, students better understood significant digits because the best one could do with a slide rule was three or four significant digits. This forced students to first express the numbers in scientific notation, which shows only the significant digits multiplied by a power of ten.

With calculators, the answer can now run to 10 or twelve digits, but still only the significant digits matter. The rest are an illusion.

Fair point, Mahtso. But given today's news that Glendale is floating $50 million in bonds to underwrite expansion of Midwestern University, perhaps it is also not accurate to say Glendale is struggling to pay its debt. No struggle at all. Just piling on more!

Craig, you hit one of my big pet peeves (being a science geek).

The worst is from Congress with the "estimates" that members are worth. I have seen something like Congressman Joe is worth between 1.585 million and 7.635 million dollars....... That is because they (at least used to) drop assets into a list of ranges (20 assets from 5 to 50 K, 3 assets between 50 and 500K, etc). Reporters just added the min and max to get their (worthless) estimates.

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