6 ms·

Can interview puzzles help find startup ideas?

22 points by nicholasjbs 16y ago

MichaelGlass 16y ago
I guess I'm not impressed by first mover advantage. I like second mover advantage. First mover advantage is subject to too many problems. Confirmation bias. Unseen players which make the better solution infeasible. etc. In the end, execution is key. I value polish over cleverness. Someone who can execute quickly and cleanly is who I want. Testing for those qualities is more difficult and interactive than simple interview questions.
- nicholasjbs 16y ago
  I don't think it's so much first-mover versus second-mover advantage but rather an overall question of timing. I agree that being first doesn't matter if the market and timing aren't right.
  - myoung8 16y ago
    The first-mover's Achilles heel, though, is that you're the one who has to affect behaviorial change, which is the hardest part about building a company that is trying to fundamentally change the way people, well, behave.
philwelch 16y ago
The page isn't loading for me right now, so all I have to go on is the title, which gives the unfortunate impression that we should be doing "wash all the windows in Seattle for a single fixed price" startups!
- nicholasjbs 16y ago
  Agh, sorry! Looking into it. I have WP SuperCache installed so I don't know what's going on.
  - patio11 16y ago
    Turn off Apache KeepAlive. You aren't pegging the CPU, are you? Right now, you're probably using 0% CPU or thereabouts, and you don't have a problem caching can solve. What you do have is a limited pool of connections. Having KeepAlive on causes any browser that grabs a connection for any reason to hold onto it for a few extra seconds, to improve its performance on subsequent requests for e.g. static resources. Unfortunately, if you have more clients than you can service, they all get to wait until the keepalive period is over so that one connection gets released, immediately satisfies an additional client with cached data, and then does nothing for another few seconds. This looks to people in the queue like your server died. Apache KeepAlive defaults to on in several popular distributions, including Ubuntu last time I checked. That default interacts very, very poorly with common conditions for blogs in 2010.
    - nicholasjbs 16y ago
      Thanks. I just turned KeepAlive off. (Edit: I don't think this was the original problem, since when the site went down the CPU was in fact pegged. Regardless, it sounds like I should have KeepAlive off.)
nicholasjbs 16y ago
Since my server is down for the count right now, here's the text of the post: --- I think there might be value to those dumb interview puzzles after all. Let me explain. Last week there was a Hacker News link to a post about a 140 interview questions Google supposedly asks. I read over some of them and was quickly drawn in. Not because I expect to be interviewing for a job, but because a puzzle like that is like a virus that infects my mind. It spreads until it’s my top idea, and then holds up residence until I solve it. After figuring out a few of them and being frustrated by how long they took me, I wondered if there were general strategies I could use to solve them. One pattern quickly jumped out at me: Almost all of these puzzles exploit blind spots in our thinking. Their answers frequently lie in assumptions we don’t even know we’re making. Have you heard the one about the four travelers who each walk at different speeds and have to cross a bridge in 17 minutes? It’s easy as soon as you realize you don’t have to send the same person back right after he crosses, and that you don’t just want to optimize for the return-trip time. Or what about the one where you have to find which of eight balls is heavier than the others, using a balance exactly twice? It’s straightforward as soon as you stop assuming you should use a divide-and-conquer approach and weigh all the balls in your first weighing. Naval Ravikant and Andrew Parker both blogged about how many popular web services have sprung from challenging assumptions about privacy. This is a specific instance of what I’m talking about. We make certain assumptions about privacy without always examining why we’ve made them. Frequently it’s the case that the assumption was valid when we first made it, but technological or social change has rendered it invalid. We still have lots of those floating around our culture. How could we not? It’s not like all of society is a giant decision-making machine that reevaluates every statement we hold to be true the second a new technology pops up. As a whole, society goes through this process gradually, as someone inevitably notices the contradiction or error in our thinking and a new order begins to spread. Jobs did this with the assumption that computers weren’t for personal use. Gates did this with the assumption that the money was to be made in the hardware rather than the OS business. If you want to build a company that changes the world, look for these assumptions. They’re in our collective blind spots. Places we don’t want to look or places we look past every day. They’re buried treasures, because the first person to identify one gets first mover advantage and a window of time in which others haven’t realized what they previously held to be true isn’t.
- 16y ago
byoung2 16y ago
I just had an interview with a few of these types of questions (find if the permutations of a given word are in a list of words, write an algorithm to fetch objects from an arbitrarily large list given that we can fetch a max of 100 at a time and users can scroll through results 10 at a time...blah blah blah). I had good enough answers and I got the job. Guess what I had to do for my first project...
- jules 16y ago
  An application that scrolls trough a list of words that are permutations of a given word 10 at a time?
  - byoung2 16y ago
    It was a photo galley app...the words in the list were tags that the user types in, and the fetching of objects was to pull images from an Api using Ajax to prefetch images and dynamically add them to the gallery as the user scrolls.

22 points by nicholasjbs 16y ago

I guess I'm not impressed by first mover advantage. I like second mover advantage. First mover advantage is subject to too many problems. Confirmation bias. Unseen players which make the better solution infeasible. etc. In the end, execution is key. I value polish over cleverness. Someone who can execute quickly and cleanly is who I want. Testing for those qualities is more difficult and interactive than simple interview questions.

nicholasjbs 16y ago
I don't think it's so much first-mover versus second-mover advantage but rather an overall question of timing. I agree that being first doesn't matter if the market and timing aren't right.
- myoung8 16y ago
  The first-mover's Achilles heel, though, is that you're the one who has to affect behaviorial change, which is the hardest part about building a company that is trying to fundamentally change the way people, well, behave.

philwelch 16y ago

The page isn't loading for me right now, so all I have to go on is the title, which gives the unfortunate impression that we should be doing "wash all the windows in Seattle for a single fixed price" startups!

nicholasjbs 16y ago
Agh, sorry! Looking into it. I have WP SuperCache installed so I don't know what's going on.
- patio11 16y ago
  Turn off Apache KeepAlive. You aren't pegging the CPU, are you? Right now, you're probably using 0% CPU or thereabouts, and you don't have a problem caching can solve. What you do have is a limited pool of connections. Having KeepAlive on causes any browser that grabs a connection for any reason to hold onto it for a few extra seconds, to improve its performance on subsequent requests for e.g. static resources. Unfortunately, if you have more clients than you can service, they all get to wait until the keepalive period is over so that one connection gets released, immediately satisfies an additional client with cached data, and then does nothing for another few seconds. This looks to people in the queue like your server died. Apache KeepAlive defaults to on in several popular distributions, including Ubuntu last time I checked. That default interacts very, very poorly with common conditions for blogs in 2010.
  - nicholasjbs 16y ago
    Thanks. I just turned KeepAlive off. (Edit: I don't think this was the original problem, since when the site went down the CPU was in fact pegged. Regardless, it sounds like I should have KeepAlive off.)

nicholasjbs 16y ago

Since my server is down for the count right now, here's the text of the post: --- I think there might be value to those dumb interview puzzles after all. Let me explain. Last week there was a Hacker News link to a post about a 140 interview questions Google supposedly asks. I read over some of them and was quickly drawn in. Not because I expect to be interviewing for a job, but because a puzzle like that is like a virus that infects my mind. It spreads until it’s my top idea, and then holds up residence until I solve it. After figuring out a few of them and being frustrated by how long they took me, I wondered if there were general strategies I could use to solve them. One pattern quickly jumped out at me: Almost all of these puzzles exploit blind spots in our thinking. Their answers frequently lie in assumptions we don’t even know we’re making. Have you heard the one about the four travelers who each walk at different speeds and have to cross a bridge in 17 minutes? It’s easy as soon as you realize you don’t have to send the same person back right after he crosses, and that you don’t just want to optimize for the return-trip time. Or what about the one where you have to find which of eight balls is heavier than the others, using a balance exactly twice? It’s straightforward as soon as you stop assuming you should use a divide-and-conquer approach and weigh all the balls in your first weighing. Naval Ravikant and Andrew Parker both blogged about how many popular web services have sprung from challenging assumptions about privacy. This is a specific instance of what I’m talking about. We make certain assumptions about privacy without always examining why we’ve made them. Frequently it’s the case that the assumption was valid when we first made it, but technological or social change has rendered it invalid. We still have lots of those floating around our culture. How could we not? It’s not like all of society is a giant decision-making machine that reevaluates every statement we hold to be true the second a new technology pops up. As a whole, society goes through this process gradually, as someone inevitably notices the contradiction or error in our thinking and a new order begins to spread. Jobs did this with the assumption that computers weren’t for personal use. Gates did this with the assumption that the money was to be made in the hardware rather than the OS business. If you want to build a company that changes the world, look for these assumptions. They’re in our collective blind spots. Places we don’t want to look or places we look past every day. They’re buried treasures, because the first person to identify one gets first mover advantage and a window of time in which others haven’t realized what they previously held to be true isn’t.

16y ago

byoung2 16y ago

I just had an interview with a few of these types of questions (find if the permutations of a given word are in a list of words, write an algorithm to fetch objects from an arbitrarily large list given that we can fetch a max of 100 at a time and users can scroll through results 10 at a time...blah blah blah). I had good enough answers and I got the job. Guess what I had to do for my first project...

jules 16y ago
An application that scrolls trough a list of words that are permutations of a given word 10 at a time?
- byoung2 16y ago
  It was a photo galley app...the words in the list were tags that the user types in, and the fetching of objects was to pull images from an Api using Ajax to prefetch images and dynamically add them to the gallery as the user scrolls.