Profile cover photo
Profile photo
Alex Quinn
1,983 followers
1,983 followers
About
Communities and Collections
View all
Posts

Tip: Set your CAMERA clock back.  I usually forget this one, and then all of my photo time stamps are off by 1 hour.

MATH PROBLEM ... You and your friends want to create a scale of sweetness (taste) for many types of fruit. Each person tastes a few fruits and scores them like this:
• Anne: banana=0.0, papaya=0.7, cantaloupe=1.0
• Bert: papaya=0.0, cantaloupe=0.4, peach=1.0
• Carl: strawberry=0.0, papaya=0.7, peach=1.0
• …

In other words, of the three fruits Anne tasted, she found cantaloupe sweetest, banana least sweet, and papaya closer to cantaloupe than to banana.

Every person will score a few (but not all) fruits. Every fruit will be tasted/scored by a few (but not all) people. Scores are all relative, i.e., no explicit units.

The end result should look something like this:
• 0.0 banana
• 0.2 strawberry
• 0.4 papaya
• 0.5 cantaloupe
• 1.0 peach

GOAL: How can I use the individual scores to calculate the global scores?

____________________________
If you recognize the form of the problem, I'd greatly appreciate a pointer.

As I see it, I need to scale and shift each person’s scores so they are compatible (or approximately so) with the others, and then renormalize them all back to 0.0 to 1.0. Originally, I thought I could express the individual scores as an over-specified system of linear equations, and solve it using least squares. I can’t figure out how to set it up for that. Maybe it needs something fancier than linear regression. I don't know.

This is for my research—part of building a system for crowdsourcing decisions.

Post has attachment
Cute song about paying income taxes

Python: Why does it take 13,703,112,000 bytes of RAM to create an array of 1,000,000,000 null values?  While executing the following statement, it peaked at 13.1 GB.  After it finished, it settled back to 7.5 GB.
>>> a = tuple(None for _ in xrange(10**9))

Last Friday, I wrote to Evernote to let them know I've been receiving bogus password reset confirmation emails periodically over the past 7 months.  The next day, they announced they had discovered a security breach affecting 50 million accounts. I can't help but wonder if I helped tip them off to the intrusion.

Post has shared content

Lately, some Republicans have quipped that only Democrats should pay the extra taxes for spending Republicans don't want. That would only be fair if there were some conditions:

• Republicans who refused to fund the Pell Grant or federally subsidized student loans would not be allowed to hire workers who were educated by them. When those people got better jobs and paid higher taxes as a result of the college education they couldn't otherwise afford, the extra taxes would go into the Democrat's pool of tax revenue.

• Republicans who refused to fund the NSF would not be allowed to use the resulting research in their businesses, or hire the graduate students who gained experience (and PhDs) by way of those projects. (Example: Both founders of Google were NSF-funded graduate students.)

• Republicans who refused to fund the NIH and CDC would not be allowed to receive medicine or medical treatments that benefited from the NIH- or CDC-funded research.

• Republican employers who forced their workers to go to the government for health care would be required to reimburse the government when those healthier employees missed fewer work days.

• Republicans who refused to fund mental health and substance abuse programs would have to pay the extra cost of police to manage the unstable people walking around, and prisons to incarcerate them when they flip out and do terrible things.

• Republicans who refused to fund public schools enough to buy modern facilities and materials, and pay salaries that attract/retain great teachers would not be allowed to hire the more competent students they produced.

• Republicans who refused to fund all of the above would not be allowed to invest in companies that benefited. That means no investments (i.e., stock, mutual funds, pensions, etc.) in the US technology, health care, pharmaceuticals, telecommunications, oil/gas, or aerospace/automotive sectors.

This is just to illustrate some of the indirect benefits people in the upper brackets receive for their tax money. It would be hard to succeed in business without workers who are competent, properly educated, and healthy. Fortunately, not all Republicans are so short-sighted, nor are all employers Republicans (or vice versa).

Post has attachment
Possibly the strangest video I've ever seen…

Post has attachment
This timer is a prized possession. As soon as the meat or fish has the optimum internal temperature, it beeps. No time calculations, cutting into the food to check doneness, or even opening the oven door to look. . . . . (Thanks, +*** for getting this for me in 2011.)
Photo

Merry Christmas! . . . I wish Christmas was quarterly, or at least semi-annual. Once a year was never enough!
Wait while more posts are being loaded