Monty Hall Problem

A classic brain teaser is the Monty Hall Problem. It fools people with a basic understanding of probability (i.e. most of us), and even after a good amount of consternation seems unintuitive. If complex mathematical formulas don’t convince you, then you’ll likely have to see it actually happen to believe it, as I did.

I came across it again today, and I was unhappy with the idea that this remained a difficult hurdle for my brain to jump, even though at this point I know the answer.  I came up with the following explanation that I think is as simple as it gets, so if it still sticks in your craw as it did mine, perhaps this will help.

If you never switch:

  • 1/3 of time you pick right door, and win.
  • 2/3 of time you pick wrong door, and lose.

(1/3 * 1) + (2/3 * 0) = 1/3

So if you never switch, you will win 1/3 of the time.

If you always switch:

  • 1/3 of time you pick right door, Monty will open either of the empty doors, and then you will open the other empty door, and lose.
  • 2/3 of time you pick an empty door, Monty will open the other empty door, and then you will open the door with the prize and win.

(1/3 * 0) + (2/3 * 1) = 2/3

If you always switch, you will win 2/3 of the time.

Diagrams and formulas aside, the phrase “the other empty door” is what made it come together for me.

Blog posts come to life: Marginal Revolution edition

As I entered the 7-11 in Central Square the other day, there was, as usual, a man seated outside the door. The unusual aspect was that another man was challenging his right to use the spot, threatening violence. As I exited the store, the two were discussing how much the new man would pay the old man for the spot. The asking price was at $0.50.

Hudson Balloon Festival

Hot Air BalloonThere’s an annual balloon festival in Hudson, MA. The festival itself isn’t much, a dozen or so local vendors, but it happens to be across the street from Reeny, so it’s hard to argue against checking it out. I was somewhat surprised that it seems fairly easy to get one in the air, you roll it out, blow a fan into it, and fire it up when it’s almost ready. I’m sure there are some tricks, but they’re typically launched by just a few people. It was also a good test of one of my new toys, the circular polarizing lens filter, which can really make the blue sky and clouds pop.

Hot Air Balloon in Flight

Hot Air Balloons at Night

Stop Buying Socks!

I try hard to avoid posting the endless stream of videos and random pictures one encounters on the internet, but this one is just too bizarre not to share. This came in a spam that not only got through my spam filters, but somehow tricked Thunderbird into displaying the image without a prompt. I’m going to have to grant it the award of “most grizzled Santa Claus ever”.

I want you to stop buying socks!

Year One

One Year Old!So I’ve been a bit absent from writing lately, and missed the 1 year anniversary of this blog. Posting will resume tomorrow, but for now, here’s a little zeitgeist for year one:

There were 48 posts and 39 comments (5 by me), contained within 51 categories. 9,496 spam comments were blocked.


Most popular posts (by page views)

  • Enabling Buttons on Apple Keyboard in Windows
  • Jet Cars 2007
  • Cy Young 2007
  • Java Package Conventions
  • Session Moratorium
  • Nice to see that these were spread across the main topics.

    Most popular categories (by number of posts)

  • Software (11)
  • Sports (9, 7 in Baseball)
  • Internet (7)
  • Movies (7)
  • Java, Mac, Windows (4 each)
  • Most popular search keywords (by visits)

  • cy young 2007
  • eric savage
  • list of cool usernames
  • eric savage blog
  • terastation live review
  • Most popular traffic sources (by visits)

  • Google
  • (direct)
  • StumbleUpon
  • Yahoo!
  • Blendlab
  • Longest Post: An Open Letter to Recruiters

    Shortest Post: Shrinkage

    This year’s goal: 100 posts. (1 down!)

    21st Century Game Changers

    A post on the Freakonomics blog got me thinking. What inventions have genuinely improved, or even affected, my life. I drew up a list, and decided to constrain it to the 21st century, so things like the cellphone, the VCR, the CD, the ATM, instant messaging, and online banking aren’t on the list. Here they are, and where possible I put the approximate year I adopted them.

    Major Improvement to Daily Life

    • Tivo (2000) – Definitely #1 on the list. I don’t consider myself a couch potato, but this completely unshackled me from the network’s arbitrary scheduling. It also make more shows enjoyable, or even watchable, by cutting out commercials.
    • RSS/Google Reader (2002, 2005) – RSS enabled me to keep track of a much broader set of sources, and Google Reader took RSS to the next level by making my subscriptions and unread articles available anywhere (including my phone).
    • Smartphone (2006) – I’m far more organized now that I have my full contact list and calendar on me at all times, as well as being backed up, plus last-resort internet access is a nice bonus.
    • TV shows on DVD (2003) – There’s now a new category of TV show, the ones I don’t even bother to Tivo and just wait for the DVD.

    Minor Quality-of-Life Improvement

    • Netflix (2002) – Like they say, no more late fees.
    • Wifi (2004) – Adopted later than most geeks, has proven useful in many ways.
    • Wikipedia (2003?) – Coming from someone who used to read the encyclopedia for fun, Wikipedia is like crack.
    • Text Messaging (2006) – Late to the game here. Enables a new layer of communcation and makes me both more responsive and more proactive.
    • GPS (2007) – I waited a while for the price dip, and now consider GPS a mandatory item for my car.
    • mp3 player/iPod (2002/2004) – No more discman and CD cases is a good thing.
    • Digital Camera/DSLR (2001, 2004, 2007) – I’m too lazy to deal with film. I got my first digital in 2001, my first nice one in 2004, and my first digital SLR in 2007, each a vast improvement over the previous.
    • Firefox (2004) – Firefox has gone from lightweight security-minded browser to bloated, customizable security-minded browser, both of which I’ve found value in.
    • Eclipse (2002) – Java wins in my book because of Eclipse. Having a program that thinks for you enables you to think about the real problems.
    • Launchcast (now Yahoo! Music) (2002) – One of the earliest and still one of the best customized music services. If you’re not sold on Pandora and Last.fm it might be because they are are inferior versions of Launch.

    (supposedly) Major Advances, Adopted by Me, Negligible Impact

    • Social Networks (2004) – I use LinkedIn as a sort of resume-light, and myspace to keep up with my sisters, and facebook as the site du jour, but they are all just curious diversions.
    • OS X (2005) – Scores high on sexiness. Scores low on stability & usability
    • XP/Vista (2003) – Windows 2000 made computers better and more useful. XP and Vista seem to just make them slower.

    Major Advances, Unadopted by Me

    • VoIP/Skype – I don’t use landlines.
    • Fastlane/Speedpass – I still find the ease with which someone can track me disturbing, plus the lines these days are usually shorter at the cash lines.

    There’s probably some that I missed, or just weren’t important enough to remember. My main question is, what’s next to get on the list, and where on the list will it end up?

    Domain Ideas

    I put “savage” into GoDaddy‘s search box, just to see what would come up, and while savage.com is obviously taken, it suggested some rather entertaining alternatives:

    • WILDDRUNK.COM – Surprised this one isn’t taken by Girls Gone Wild.
    • FERAL4U.COM – A site that matches wild animals with potential owners?
    • HOTFERAL.COM – Which animals are trending in your area?
    • UNCIVILIZEDLIVE.COM – Future site of the world’s largest rock-banging concert.
    • WILDTHIN.COM – The latest diet fad, lose weight by eating berries, running from bears, and getting dysentery.
    • BARBAROUSSTORE.COM – Because pirates and drug lords need pants too.

    Savage: The Movie

    Saw this over at Matt’s LJ, seemed interesting.

    IF YOUR LIFE WERE A MOVIE, WHAT WOULD THE SOUNDTRACK BE?
    REMEMBER, DON’T CHEAT!
    So, here’s how it works:
    1. Open your library (iTunes, Winamp, Media Player, iPod, iPaq etc)
    2. Put it on shuffle
    3. Press play
    4. For every question, type the song that’s playing
    5. When you go to a new question, press the next button
    6. Don’t lie and try to pretend you’re cool…

    Note: I skipped the song if the same artist came up again.

    Opening Credits: Dr. Dre & Ice Cube – “Natural Born Killaz”
    What kind of movie is this going to be?

    Waking Up Scene: Susie Van Der Meer – “Somebody Has to Pay”
    From the Run Lola Run soundtrack, not a bad choice for a breakfast montage.

    Walking Down The Street Scene: House of Pain – “House of Pain Anthem”
    This could be funny, fitting or tragic depending on which street we’re talking about.

    Car Driving Scene: The Police – “Don’t Stand So Close to Me”
    Eh, not a great fit.

    High School Flashback Scene: Mr. Mackey – “It’s Easy, Mmkay”
    Nice choice here. Life advice, South Park stylee.

    Drug Abuse Flashback Scene: Blue Swede – “Hooked on a Feeling”
    Bizarre.

    Summer/Beach Scene: Blink 182 – “All the Small Things”
    Good beach music.

    Nostalgic Scene: Insane Clown Posse – “The Neden Game”
    Just can’t make this one work.

    Bitter, Angry Scene: Nine Inch Nails – “Where is Everybody?”
    Few better choices than Nine Inch Nails for bitter music.

    Break-up/Throwing Things/Slow Motion Scene: The Dust Brothers – “Psycho Boy Jack”
    If you broke up in a run down gas station with flickering flourescent bulbs, this would be a good choice.

    Regret Scene: Ahmad – “Back in the Day”
    Title works, song doesn’t.

    Bar Scene: Air – “The Vagabond”
    Harmonica, hand clapping and Beck, sounds like a good bar to me.

    Nightclub Scene: Underworld – “Ballet Lane”
    It fits if its a laid back club full of people sipping amaretto.

    Fight/Action Scene: Green Day – “Basketcase”
    Eh, can’t imagine this song causing any fights.

    Sad, breakdown scene: Korn – “Lost”
    Angsty, gritty, good pick.

    Death Scene: Hüsker Dü – “M.I.C.”
    Pacifist punk song, bad fit.

    Funeral Scene: Moby – “My Weakness”
    Kinda sad I guess.

    Mourning Scene: Beastie Boys – “Eugene’s Lament”
    Probably the best pick of the bunch.

    Mellow Scene: Kittie – “Immortal”
    Instrumental Kittie song, I guess that passes for mellow.

    Dreaming About Someone Scene: Bjork – “Sod Off”
    Dreaming about pre-emptively dumping someone.

    Sex Scene: Kompressor – “Vitamins are Good”
    Bizarre.

    Contemplation Scene: Outkast – “Prototype”
    Well he says “i think” alot…

    Fancy Party: Ministry – “Psalm 69”
    Not too fancy.

    Realization Scene: 311 – “Fat Chance”
    Realizing one of your favorite albums is almost over.

    Flashback/Build up Scene: Howlin’ Wolf – “Moanin’ at Midnight”
    This song begs for sepia tone.

    Chase Scene: Mudvayne – “Nothing to Gain”
    Hmm, wouldn’t work for a car chase, maybe a foot chase through the city.

    Happy Love Scene: Marilyn Manson – “The Speed of Pain”
    Might work with a loose interpretation.

    Happy Friend Scene: Cut Chemist meets Shortkut – “No Mistakes in this Number Son”
    Not a bad fit.

    Closing Credits: Basement Jaxx – “Same Old Show”
    Decent credits song.