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User: cgenman

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  1. Re:Trackball on The "King of All Computer Mice" Finally Ships · · Score: 1

    Can you recommend a good thumb-based trackball for gaming?

    I've been a devoted user of Kensington's Expert Mouse Trackball for years. But I found during a binge of TF2 that I had to switch to a basic optical mouse. If there were a good trackball gaming option, I would definitely return.

  2. Re:Ordering and Convergence on The Tuesday Birthday Problem · · Score: 1

    Here is a simpler version: I have two children. One of my children is a boy. What is the possibility that the other one is a boy too?

    Before you say 50%, let's rephrase the question in two steps: I have two children. What is the possibility that both of my children are boys? Knowing that I don't have two girls, now what is the possibility that both of my children are boys?

    The possibility set for children is
    Boy Girl
    Boy Boy
    Girl Boy
    Girl Girl

    Thanks to that last piece of information, we can eliminate Girl / Girl from the list of options, which leaves us with
    Boy Girl
    Boy Boy
    Girl Boy

    There is only one possibility out of three with Boy / Boy, which only gives us a 33% chance of a Boy Boy. People intuitively expect to be able to say "If child 1 is a boy, then child 2 should be a boy or a girl. If child 2 is a boy, then child 1 is a boy or a girl. Therefore, boy boy happens 50% of the time." But that's wrong, as you're counting the single possibility of Boy / Boy twice.

    The problem above is exactly the same, except with an additional day of the week tacked on. The possibility of a boy born on Tuesday can only be counted once. You'd expect it to have no relevance, but since you don't know WHICH boy is born on tuesday, you have to look at the overall possibilities. And looking at overall, if the first child is a boy born on tuesday, there are 7 possibilities for boys and 7 for girls for the second child. It's almost the same thing for the second child, but you have to remove one of the Boy Tuesday / Boy Tuesday possibilities since you already counted it in the first set. That leaves 6 / 7.

    The bigger the set of additional information that you tack on, the closer that possibility will approach 50%. But it is never quite 50%, because there is always that one reduntant possibility that you have to eliminate from the problem set.

  3. Re:Ordering and Convergence on The Tuesday Birthday Problem · · Score: 1

    I crunched the numbers. There are only 196 permutations, few of which are valid, so one could probably do so by hand.

    http://slashdot.org/comments.pl?sid=1701394&cid=32733372

    His phrasing is weird. The analysis would have been a lot more obvious if he had said "Either the older child is a boy born on tuesday, or the younger child is a boy born on tuesday", and then removed the possibility of a Boy Tuesday / Boy Tuesday birth from the second set, since it was already counted in the first set.

  4. Re:Ordering and Convergence on The Tuesday Birthday Problem · · Score: 1

    Having the machine spit out the possibilities:

    boy monday : boy tuesday
    boy tuesday : boy monday
    boy tuesday : boy tuesday
    boy tuesday : boy wednesday
    boy tuesday : boy thursday
    boy tuesday : boy friday
    boy tuesday : boy saturday
    boy tuesday : boy sunday
    boy wednesday : boy tuesday
    boy thursday : boy tuesday
    boy friday : boy tuesday
    boy saturday : boy tuesday
    boy sunday : boy tuesday
    boy tuesday : girl monday
    boy tuesday : girl tuesday
    boy tuesday : girl wednesday
    boy tuesday : girl thursday
    boy tuesday : girl friday
    boy tuesday : girl saturday
    boy tuesday : girl sunday
    girl monday : boy tuesday
    girl tuesday : boy tuesday
    girl wednesday : boy tuesday
    girl thursday : boy tuesday
    girl friday : boy tuesday
    girl saturday : boy tuesday
    girl sunday : boy tuesday

    Notice that Tuesday / Tuesday is swallowed within two separate runs. Intuitively, you'd expect 4 sets of 7 possibilities: Boy Tuesday Boy MTWTFSS, Boy MTWTFSS Boy Tuesday, Boy Tuesday Girl MTWTFSS, Girl MTWTFSS Boy Tuesday. But from a top-down view, any overlap between those sets can't count twice, so you lose one of the Boy MTWTFSS / Boy Tuesday sets. Instead of 28 full possibilities, you get 27, and instead of 14 boy / boy sets you get 13... Thanks to having to remove 1 redundant option from the expected set.

    Which is, as it turns out, exactly what the original analysis said (though without calling out why). So it is completely correct, and I stand (err, sit) corrected.

  5. Re:Ordering and Convergence on The Tuesday Birthday Problem · · Score: 1

    I'll be damned. Since futzing about with the kids possibilities seemed too indirect, I just wrote the following program to enumerate all 196 possibilities. As it turns out, I'm just wrong.

    var child1Gender:Array = new Array("boy", "girl");
    var child2Gender:Array = new Array("boy", "girl");
    var child1Week:Array = new Array("monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday" );
    var child2Week:Array = new Array("monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday" );

    var totalCombinations:Number = 0; //should reach 196
    var validCombinations:Number = 0; //number where one child is a boy on tuesday
    var boyBoyCombinations:Number = 0; //combinations where both are boys // Enumerate through the possibilities
    for( var c1g:Number = 0; c1g child1Gender.length; c1g++ ){
            for( var c2g:Number = 0; c2g child2Gender.length; c2g++ ){
                    for( var c1w:Number = 0; c1w child1Week.length; c1w++ ){
                            for( var c2w:Number = 0; c2w child2Week.length; c2w++ ){
                                    totalCombinations++; //Is this a valid combination?
                                    if( ( child1Gender[c1g] == "boy" && child1Week[c1w] == "tuesday" ) || ( child2Gender[c2g] == "boy" && child2Week[c2w] == "tuesday" ) ){
                                            validCombinations++;
                                            if( child1Gender[c1g] == "boy" && child2Gender[c2g] == "boy" ){
                                                    boyBoyCombinations++;
                                            }
                                    }
                            }
                    }
            }
    }
    trace("Total Combinations (should be 196): " + totalCombinations );
    trace("Valid Combinations: " + validCombinations);
    trace("Boy / Boy Combinations: " + boyBoyCombinations);

    That gives 27 total combinations, 13 of which are boy / boy. Or, there is only a 48% chance that the other child is a boy. Damned enumerability.

  6. Re:Ordering and Convergence on The Tuesday Birthday Problem · · Score: 1

    My reading, of their analysis, and correct me if I'm wrong:

    They start with the assumption that the older child is either the boy born on Tuesday, or not. And they enumerate each set of options for the other child.

    If the elder is a boy born on tuesday, the younger child is either a boy born any day of the week, or a girl born any day of the week. That's 14 possibilities.
    If the elder is not the boy born on tuesday, the younger child must be. Then the elder is either a girl born on any day of the week, or a boy born on any day BUT tuesday.

    They then add up all the possibilities, and sure enough one possibility is missing. You get a 13/28 chance of a boy, rather than a 14 / 28 (1/2, or 50%).

    The problematic seeming part, in my opinion, is that we're assuming all of these possibilities to be equal. Instead of saying that "The elder is a boy born on tuesday, or the younger is a boy born on tuesday" we're saying that "the elder is the boy born on tuesday, or he isn't." Those are not mathematically equivalent. Assuming the boy was chosen at random, and that both children could fit the same description (which we assume in the prior analysis), there is a 1/14 chance that if the older boy is not the boy randomly selected to be described, he will still meet that description anyway. This is an assumption which is missing from the above analysis. Conveniently, this perfectly fills the expected possibility gap, and gets us to 1/2.

    Another analysis would say that either the elder is a boy born on tuesday, or the younger is a boy born on tuesday. Then the possibilities would be
    Elder BTuesday + Younger B SMTWTFS G SMTWTFS
    or
    Younger BTuesday + Elder B SMTWTFS G SMTWTFS

    If they do declare exclusivity (one is a boy born on Tuesday, and the other is not), which is not listed in the problem, then of course the extra information will take out some possibility of the other child being a boy. Seeing as how boys are born on 1/7 of the days, you'd expect to see 1/7th less than expected boys, while girls would retain their full normal share. But the way the prior analysis is done, they seem to be assuming exclusivity in one part of the problem but not the whole thing.

    Again, please correct me if I'm wrong.

  7. Re:Steve responds on iOS Update May Tackle iPhone 4's Antenna Problems · · Score: 1

    Time Capsule is actually about the easiest thing I've used, and is one thing that I'm tremendously jealous about in the windows world.

    For those who don't know, Time Capsule is both a piece of hardware, and the Time Machine software built into the OS. When you plug in an external hard drive, the OS asks if you'd like to use it as a backup drive. If you say yes: You're done. Any time you plug that hard drive into your system, it automatically creates an incremental backup silently in the background, with minimal performance hit. You can then basically travel backwards in time to any previous version of a file in a straightforward, easy-to-use interface. Due to the incremental nature, the system stores far, far more than you would expect. It's super easy and just works.

    Sure, automatic incremental backups have happened before. And version control is a very old concept. But nobody has done it as easy as Apple has here. It doesn't pop-up in a taskbar, it doesn't fail because it was expecting the drive at 3am, it doesn't jam full of uncompleted changes to save. It's the easiest backup system I have ever used, and I have used a lot.

    I can't speak for hardware durability, as I haven't seen numbers on failure rates. But I'll be damned if Time Capsule and Time Machine didn't significantly raise the quality and painlessness bar for backups.

  8. Re:Hmmm... on VP8 Codec Coming To FFmpeg · · Score: 1

    MPEG-LA charges for encoding as well as decoding.

  9. Re:Why not a weekday? on Amazon Opposes Plan To End Saturday Mail Delivery · · Score: 1

    And businesses who rely upon mail services will get it all the following day. Bills not going out will go out the following day, will be sat upon by people for weeks anyway, and will finally be returned. Checks coming in will come in a day later.

    Business is moving to an online payment space anyway. You can't sell to grocery stores in the northeast anymore without an automated infrastructure.

    Is waiting and extra 1/2 day really that much of a hassle, for stuff that wasn't important enough to fax?

  10. Re:USPS isn't a State Function on Amazon Opposes Plan To End Saturday Mail Delivery · · Score: 1

    When there are a plethora of confusing local regulations, the federal government usually sets up a "fair market" price for things (like radio play, etc).

    Peg online taxes at 6%. 3% goes to the city where the product is being delivered. 3% goes to the city of the fulfiller. In case of being spread across multiple cities, the fulfiller can choose. If New Hampshire, for example, doesn't want the tax, they can donate it to the feds.

  11. Re:Jack up the price? on Amazon Opposes Plan To End Saturday Mail Delivery · · Score: 1

    Does anyone really need deliveries in that one day windows, but aren't willing to pay for UPS 2 or 1 day delivery? Personally, I feel like you could be fine with Monday, Wednesday, Friday, Saturday deliveries. Anything that goes through the mail wasn't time-sensitive enough to e-mail, fax, or overnight.

    I bought a backpack and a teapot from amazon at about the same time, with the same shipping. The backpack arrived in 3 days. The teapot took about 40. Had the backpack taken 4 days, and the teapot 41, it would have been the same to me. Regular shipping is not for time-sensitive materials.

  12. Security? on How HTML5 Will Change the Web · · Score: 4, Insightful

    HTML5 will improve security

    While I love many things about HTML5, the idea of throwing out rendering libraries and starting again from scratch does not necessarily fill one with confidence about the security of the tools. Sure, less reliance on plug-ins means less opportunities for 3rd party security holes. But doing everything in the browser code itself also means that the potential attack vectors have more direct control over the machine. Plus any new library is going to have security vulnerabilities for a while.

    I'm not saying HTML5 is insecure. But let's not kid ourselves: there will be a year or two of scrambling to fix new attack vectors.

  13. Re:Its the ISPs fault? on Cheap ADSL Holds Up 802.11n Router Design · · Score: 1

    I have an 802.11g router with huge external antennas, and an 802.11n router with two internal ones. This is in a noisy wireless environment, with lots of brick and other obstructions. The 802.11n router still has about twice the range of the 802.11g one.

    As much as I love OpenWRT (though I use Tomato), does it support any N-routers?

  14. Re:DO NOT WANT: print server, storage, P2P daemon, on Cheap ADSL Holds Up 802.11n Router Design · · Score: 1

    I've never done this in an attic space, but I've had an overheating cable modem in a regular room during summer hours.

    I took an 80mm case fan, wired it to a 9v wall wart, and created a cardboard air funnel from the case fan to the modem. Shockingly enough, it actually helped improve reliability.

  15. Re:DO NOT WANT: print server, storage, P2P daemon, on Cheap ADSL Holds Up 802.11n Router Design · · Score: 1

    Every time I hear the term "business class" I think about all the businesses I've worked with over the years. All they wanted was the features of a consumer router (maybe with the annoying Microsoft login stuff), but that didn't crash / die all of the time. Except the ones willing to shell out to Cisco, they were all chased back to consumer grade electronics when their "business class" stuff died two years in the pipe.

    Make it reliable. That's all we care about at this point.

  16. Doesn't make sense to develop 2? on Developers Expect iOS and MacOS To Merge · · Score: 4, Insightful

    "It doesn't make sense for them to be developing two of everything, one good, one not as good--two calendars, two address books--it's got to merge somehow."

    I can't imagine how a calendar developed for a 2" touchscreen could have the same interface as a calendar developed for a 21" keyboard-and-mouse, and not have it be terrible. Similarly, a copy of Word on the iPhone and a copy of Word on a PC would necessarily need to have very different interfaces... You can't get hover tips on a touchscreen, people don't gesture with keyboards, mice aren't multitouch, and iPhone screens are tiny.

    The idea that you can write one app and have it work on such disparate devices shows a fundamental lack of understanding of good design.

  17. Re:ALL copyright is a restriction on free speech. on Court Takes Away Some of the Public Domain · · Score: 1

    To be fair, it is the court ruling that Congress has the power to reinstate copyright on items if Congress so chooses.

    Considering congress is the highest legislative body in the land, and the constitution doesn't really talk about copyrights, on a strictly interpretive level they should have the power to state or re-instate copyright or otherwise alter the system as they see fit.

    Of course, the problem is that we know they're going to muck the damned thing up. But congress being incompetent at their job is not a sufficient reason to strip the entire legislative body of that job. I'd encourage everyone to think of how this could be structured in a new bill of rights, and create such a thing as a legislative baseline (or constitutional amendment) to which we can use to hold our senators feet to the fire.

  18. Re:Green?? on Europe To Import Sahara Solar Power Within 5 Years · · Score: 1

    Can you back any of that up with hard statistics?

    Really, the question is one of tradeoffs. If you use the land a few miles outside of a major city such as Cairo, the additional roads required should be minimal. Unlike Coal, you don't need to trek the material in constantly. Also, it's not like major construction is unheard of in Egypt, though I bet many basic construction materials are much cheaper there than in the UK. Considering the manpower that goes into an oil plant vs a solar plant, you should have far fewer buildings and less personnel overall.

    If you're exporting the power, and it is only providing a percentage of Europe's needs, you probably don't need to store the power at all. There is currently quite a bit of overcapacity on the grid at night anyway. As part of a balanced power plan storing the power at night isn't needed.

    Other than the batteries, all of the charges you've leveled at Solar could be applied to Coal or Gas as well, with the added caveat that Coal or Gas's environmental impact should include all of the excavation and drill work that goes into those power sources. Finding, excavating, transporting, and processing coal are all dirty, nasty subjects.

    Solar power is renewable in that we're not going to hit peak solar any time soon. It also doesn't spill out into the ocean, and we don't have to go to war when OPEC decides they need new sportscars. It doesn't contribute directly to Carbon Dioxide levels (other than basic construction, which other plants would need too). And it reduces the leverage than any one energy supplier has over us.

    Major solar rollouts such as this one probably won't be completed until at the soonest 2020. That just happens to be a frequent estimate of when peak oil will hit. In today's climate, renewables and oil-based power generation is running pretty close on costs. As the cost of oil continues an inevitable rise, the balance sheet is only going to skew in solar's favor.

  19. [ot] Re:Can't wait to see on iOS 4 Releases Today · · Score: 2, Insightful

    This is just my personal opinion, but there doesn't seem to have been as much Apple fanboism here as their used to be. Or FOSS fanboism. Or even anti-Microsoftism. The big evil one hasn't done anything big and evil in a while, and isn't nearly as relevant as they used to be. Linux passed from a meme into a tool, one that is stable and not terribly exciting. Like a hammer. And the diehard Apple fanbois seem to have evolved from worshiping at the feet of Jobs to admiring the hardware and complaining about the policies.

    There are still a lot of Free-Market-Fundies around, but they seem to be everywhere these days. And the Anti-Copyright Crusaders have added a lot of noise to /. discussions over the past few years. There is a lot of overlap there with the Anti-Corporates. And the Android worshipers are getting a little annoying, but are nowhere near as bad as the other fanboys used to be. They seem to be in balance with the Anti-Google / Pro Privacy twin groups.

    I know that's not a lot of evidence presented above, just personal opinion. But the pendulum seems to have moved.

  20. Re:Can't wait to see on iOS 4 Releases Today · · Score: 1

    Even then, knowing what you want is a misnomer. People can only "want" things or concepts presented to them. If you say "Do you want more storage in your phone?" people can say yes or no. If you ask them what they want, unless the concept has been presented to them they probably won't say "an automatic calendaring system that can negotiate open times in schedules to do tasks." But they do want something that helps stuff to get done. Given the survey feedback from above, a company would probably just increase the amount of storage on the phone, without investing the development time in something revolutionary that people would *really* want if they ever saw it in use.

    - survey guy

  21. Re:Unfortunately on iOS 4 Releases Today · · Score: 1

    Some of those hardware limitations are overcome on 3rd party app stores. It looks like some features won't be available due to hardware limitations and some features won't be available due to creating the perception of value with higher-end phones.

  22. Re:Unfortunately on iOS 4 Releases Today · · Score: 1

    What's the difference in your data between "Apple iPhone" and "Apple iPhone 1G?"

  23. Re:The iPhone and finally walk and chew gum! on iOS 4 Releases Today · · Score: 1

    I use streaming Pandora for a car radio, which makes it difficult to check directions on a map or e-mail. Similarly, I'll be writing a response post to something, and will need to switch over and check a piece of data somewhere. Because of how the phone is setup, there is no guarantee that when I return to the original page, the response post will still be there or that the session will even still be valid.

    Multitasking would allow for staying on IM sessions while updating calendars. Or background uploading of photos to FTP sites while still using the phone. Background map apps that beep when you get to your destination.

    It's not a be-all-end-all of anything, but it is an expected way that modern computers behave. It will be nice to flip away from something, flip back, and have it properly remember what was going on (rather than all of the half-arsed implementations now that might work properly, and might erase everything and start you over again). Or keeping an IM window open in the background.

  24. Re:Why? on iOS 4 Releases Today · · Score: 1

    Because updating to Apple's latest and greatest as soon as possible is always a good idea that never results in bricked electronics, decreased wireless signals, scratch problems, or occasional drowsiness.

  25. Re:way to drive on Geologists Might Be Charged For Not Predicting Quake · · Score: 1

    The science of predicing earthquakes has so far bordered on Phernology. I don't mind a learning curve, even a 100 year one. But if they led people to believe that something was going to happen, and there were negative consequences because of it, they should be hung out to dry like the rest of us. Not for being wrong, but for basing a strong conclusion on incredibly flimsy ground.