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Thanks. Why can't all math teachers talk like that? I mean... I know you're clever and all, but if you were really clever you'd explain it in a way that's

Thanks. Why can't all math teachers talk like that? I mean... I know you're clever and all, but if you were really clever you'd explain it in a way that's easy to understand. Still, kudos to the OP. That was a great attempt to be precise.

axitanull 9y ago
Understanding is one thing, explaining in layman or easy to undertand terms is another, and sometimes it takes a lot of effort.
- wickawic 9y ago
  Explaining is usually more difficult than understanding, as well.
  - southpawflo 9y ago
    I've had multiple teachers tell me that if you can't explain something you don't completely understand it yet. grok what I'm saying? :)
    - nostalgiac 9y ago
      I've heard this a few times but thoroughly disagree. Being able to explain/teach something to others is a very different skill to understanding it and isn't compulsory.
- anonytrary 9y ago
  https://www.youtube.com/watch?v=FjHJ7FmV0M4 https://www.youtube.com/watch?v=FjHJ7FmV0M4 You guys would love Richard Feynman.
  - deleted 9y ago
    [deleted]
  - TangoTrotFox 9y ago
    Another resource there: http://www.feynmanlectures.caltech.edu/ http://www.feynmanlectures.caltech.edu/ That collection is a series of lectures from Feynman, and his characteristic clarity, on physics across the breadth of all major topics. It's quite amazing to realize how little you, in general, truly understand even really basic concepts like the conservation laws until you read the writings of a person who did genuinely understand what he was talking about and could share that insight in such a uniquely effective way.
modeless 9y ago
That simple explanation is exactly wrong though! You don't expect to wait 2x the average. You expect to wait 1x the average, but you also expect that when you start waiting the previous block happened 1x the average time ago, and 1+1=2.
- lordnacho 9y ago
  This is the best explanation of the phenomenon. Simple and actually explains why it's 2x and not 3x or 4x.
  - thaumasiotes 9y ago
    Is it actually true though? Compare these two comments buried downthread: https://news.ycombinator.com/item?id=16470358 https://news.ycombinator.com/item?id=16470358 > The hitchhiker's paradox is correct, taking a point and looking backward or forward will correctly give an average event 10 minutes away, but combining the events to give an average of 20 minutes is false. https://news.ycombinator.com/item?id=16471544 https://news.ycombinator.com/item?id=16471544 > I thought this sounded funny, and I did a little simulation to see if it was correct. Given his assumptions (poisson with lambda 10), you do not get that answer. I got right around 10, which is what I would expect.
    - modeless 9y ago
      Yes, it is true. I'm not sure what the first commenter is trying to say exactly. The second commenter's code was wrong, and correcting it gives the expected 20 minute average period.
- etoir 9y ago
  But you are waiting 2x the average, because the average waiting time should be half of the period. Consider buses which arrive every ten minutes, exactly. You arrive at the bus stop at a random time. How long should you expect to wait? Not 10 min but 5 min, on average. You are equally likely to arrive at any point during the 10 minutes wait. Now change the buses to a Poisson process with mean rate 1 bus every 10 minutes. Now you arrive during an interval of average length 20 min, but wait on average 10 min.
mnw21cam 9y ago
An expert is someone who can take something you already understand, and make it sound confusing.

axitanull 9y ago

Understanding is one thing, explaining in layman or easy to undertand terms is another, and sometimes it takes a lot of effort.

wickawic 9y ago
Explaining is usually more difficult than understanding, as well.
- southpawflo 9y ago
  I've had multiple teachers tell me that if you can't explain something you don't completely understand it yet. grok what I'm saying? :)
  - nostalgiac 9y ago
    I've heard this a few times but thoroughly disagree. Being able to explain/teach something to others is a very different skill to understanding it and isn't compulsory.
anonytrary 9y ago
https://www.youtube.com/watch?v=FjHJ7FmV0M4 https://www.youtube.com/watch?v=FjHJ7FmV0M4 You guys would love Richard Feynman.
- deleted 9y ago
  [deleted]
- TangoTrotFox 9y ago
  Another resource there: http://www.feynmanlectures.caltech.edu/ http://www.feynmanlectures.caltech.edu/ That collection is a series of lectures from Feynman, and his characteristic clarity, on physics across the breadth of all major topics. It's quite amazing to realize how little you, in general, truly understand even really basic concepts like the conservation laws until you read the writings of a person who did genuinely understand what he was talking about and could share that insight in such a uniquely effective way.

modeless 9y ago

That simple explanation is exactly wrong though! You don't expect to wait 2x the average. You expect to wait 1x the average, but you also expect that when you start waiting the previous block happened 1x the average time ago, and 1+1=2.

lordnacho 9y ago
This is the best explanation of the phenomenon. Simple and actually explains why it's 2x and not 3x or 4x.
- thaumasiotes 9y ago
  Is it actually true though? Compare these two comments buried downthread: https://news.ycombinator.com/item?id=16470358 https://news.ycombinator.com/item?id=16470358 > The hitchhiker's paradox is correct, taking a point and looking backward or forward will correctly give an average event 10 minutes away, but combining the events to give an average of 20 minutes is false. https://news.ycombinator.com/item?id=16471544 https://news.ycombinator.com/item?id=16471544 > I thought this sounded funny, and I did a little simulation to see if it was correct. Given his assumptions (poisson with lambda 10), you do not get that answer. I got right around 10, which is what I would expect.
  - modeless 9y ago
    Yes, it is true. I'm not sure what the first commenter is trying to say exactly. The second commenter's code was wrong, and correcting it gives the expected 20 minute average period.
etoir 9y ago
But you are waiting 2x the average, because the average waiting time should be half of the period. Consider buses which arrive every ten minutes, exactly. You arrive at the bus stop at a random time. How long should you expect to wait? Not 10 min but 5 min, on average. You are equally likely to arrive at any point during the 10 minutes wait. Now change the buses to a Poisson process with mean rate 1 bus every 10 minutes. Now you arrive during an interval of average length 20 min, but wait on average 10 min.

mnw21cam 9y ago

An expert is someone who can take something you already understand, and make it sound confusing.