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That is a well written answer. I knew the material presented but I still found it a fun read. With all the crap that goes around, sometimes it's just nice to see the internet living up to its potential.

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Maybe a better title would be "People have a funny sense of what is relevant." That is, people have complicated ways of placing value on things. In the case of scaling the test to 137 points so the average comes out closer to 100 is silly in some ways it satisfies the students conditioning to thinking a 100 is a great score. I find the example sad in several ways (Is the teacher testing to material above what is being taught? Do the students care more about the score than actually learning something? probably...) but wanting a 100 is not irrelevant to the students.

I just bought a blue car. The color makes no difference in the performance of the car. That doesn't mean it was irrelevant to me.

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I don't think utility is quite the point...

"Combo Breaker is a motorized, battery powered, 3D printed, Arduino-based combination lock cracking device. It is portable, open source, 3D models provided, and exploits a new technique I've discovered for cracking combination locks in 8 attempts or less, but in an even more exciting, automated fashion."

This is getting close to optimal for an HN post. Too bad it wasn't programmed with Erlang. :)

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Interesting. The previous method I was aware of for cracking a combination lock of this type required a maximum of 80 attempts. I'll have to try out the new technique manually.

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Details here:

https://www.youtube.com/watch?v=qkolWO6pAL8&feature=iv&src_v...

He exploits the fact that the last dial impinges on the shackle collar to reduce it to 8 attempts. A small manufacturing change could raise it back to the higher number of attempts.

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> A small manufacturing change could raise it back to the higher number of attempts.

Even 80 attempts isn't a tall barrier when you're cracking in an automated fashion.

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It's not even a particularly tall barrier for cracking manually.

The face of the lock implies 64000 combinations. Knowledge of the internals reduces that by 99.875%. That's almost 3 whole orders of magnitude, and reduces the absolute worst case scenario for opening the lock to about 45 minutes. The attack need not take place all at the same time, either, and once completed, the lock can be opened in the same amount of time an authorized opener takes.

Don't use this type of lock to protect anything valuable, kids. It deters snoops and casual thieves only. Use it to secure your bike, and both may be gone when you return.

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Reminds me of tagging along with my older brothers to mow lawns. After a few hours of weeding and taking my turn at the push mower they would take me to get a Slurpee. My own Slurpee that I didn't have to share!

Later in high school doing construction work for my dad digging ditches with a pick and shovel, he would walk by and casually ask if I was feeling motivated to do well in school.

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Yep, as a teenager I cleaned out urethane spray booths and other shit jobs no one else would do. That motivated me to do quite quite well in electrical engineering.

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Not that long ago. A copyright term of life plus 70 years would mean that protection ended in 1980. Well, 1980 seems like a long time ago now but I was there.

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Stuff published in the 1800s wouldn't have ever had the life-plus-70 term, they'd have the shorter fixed term-plus-renewal scheme from the 1831 and 1909 copyright acts.

For anything that was unpublished, you're right, though if they'd been found and published before 2002, they'd still be protected until 2047.

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Having just moved to the interviewer side I appreciate the remarks about wanting the interviewee to succeed. I know how stressful it can be doing an interview and really do try to make it something where I can judge the ability to code, not just ability to interview. I usually try to start with something simple to just get some code going - like "We're going to need some random numbers. Make a little function that returns a list of 100 random numbers between 0 and 10." At that point I can start asking questions about why they do something a particular way and what conditions would make them do something different. Once that gets going the stress usually drops noticeably.

One other point I would add is to know the difference between being relentless and just making things up when you run up against the end of your competence. Same as mentioned in the article I will try to push out to the limit of the interviewee and a simple "I don't know for sure, maybe something like ....?" at least lets me know you know your limits. Hopefully it's not right after the first question but really don't just start making things up.

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What is the comical witticism referred to in the post script?

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The footnote to the German original says that the derivation is described in more detail in this letter to Lorentz:

http://einsteinpapers.press.princeton.edu/vol5-trans/249

(It's the section beginning "I have little that is new to report in physics".)

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What I got from the article:

"Save the world" = really, really hard.

"Improve the world" = challenging, but doable.

It seems like I have my "save the world" visions as I'm getting ready for bed and trying tho think through what I can do the next day. In the morning it seems hard enough to do mundane chores let alone get everything set up to save the world. I think my most productive times are when I've found something tangible I can make better and work through it in small steps.

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The idea is that if there is any bijection at all between the two sets then they are the same "size". So you can make all kinds of relations between two sets that are not bijections but once you find one you have satisfied the definition of same size in this sense. Note that it is a way of defining size that corresponds to what we mean with finite sets and then extends that definition in a consistent way.

So yes you could define a "malandrew size" however you like and see what kind of insights you get.

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I have a friend who grew up in a home where her mom and grandma spoke to her only in Spanish and her dad only spoke to her in English. She was surprised when she went to Kindergarten and her teacher spoke English. She thought Spanish was what women spoke and that English was for men.

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I am American and my wife is Cambodian. We live in a Cambodian neighborhood in the United States. We have a daughter, born in Cambodia, who is now 4. I speak to her in English and her mother (and everyone else in the neighborhood) speaks to her in Cambodian. Until she started preschool last September, virtually everyone except myself talked to her in Cambodian.

Not too long ago, she asked me why some person (I think it was a waiter at a restaurant) spoke English and not Cambodian. For her, everyone spoke Cambodian, and then some of them also spoke English. I tried to explain that in America, most people actually speak English and not Cambodian. After that explanation, she kept asking "is this place America?" everywhere we went for a few days.

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She thought Spanish was what women spoke and that English was for men.

I know a woman who grew up in Germany, and whose parents spoke Polish at home.

As a child she was convinced that German was for children, and Polish is the language you speak when you've grown up.

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I know a German couple where both parents speak English and German. (Though the wife is much more comfortable with English than her husband.) The way they interact with their daughter is that the father always speaks German to her, and the mother always speaks English. At one point, the mom had to tell her daughter that "you have to have daddy read you that book, because it's in German." :)

It's working pretty well so far for their daughter; she's certainly comfortable and fluent (for her age) in both languages.

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Generalizing from a single case can be tricky. I read this somewhere: "I had a friend growing up whose mom is white and dad is black. Apparently when he was little, he asked his mother why white people had vaginas."

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