Thursday, May 21, 2009

Context and song appeal

Yesterday, I mentioned that it is a bit early to state that the success of Pandora and is purely based on the strengths of their recommender algorithms. The newest copy of Psychology of Music contains an article by Silva and Silva on how successful various methods of increasing a unknown song compare. I should caution this is a preliminary study and all conclusions should be taken in this light.

Anyway, the authors had students listen and judge an unknown song in various contexts. Their findings were that the students gave the unknown song higher ratings if the students read an article about the artist of the unknown song, if a well-known and positively liked song followed the unknown song, or if a music critic praised the song prior to its playing. The authors also argue that repeated exposure to a song does not increase a song's appeal, which is a stark contrast to the most common method employed by radio stations (ahem, Payola). However, I think the argument is a little weak, since (as the authors note), they repeated the song six times in a row. Their premise behind the "repeated exposure is beneficial" hypothesis was based on the Pavlovian condition, but I disagree. The Pavlovian effect works by associating an emotional neutral action (ringing a bell around a dog) to a positive or negative association by pairing the two together (ringing a bell around a dog and then feeding him). Done correctly, the subject will associate the neutral action positively (dog salivates when the bell is rung, regardless if food is around). For starters, they did not test the premise since they gave repeated exposure without any pairing of a positive or negative stimulus.

However, we can ask what if some these are true? How does this change how we view recommenders like Pandora and First, comparing radio stations is problematic if done in series because if there is a truly positive song, then songs around it would be viewed positively. In other words, the rich get richer. In order to remove the music critic affect, one needs to establish "placebos" so that users cannot infer a playlist is better than another for reasons other than the audio. For example, if users know that their ratings are taken into consideration ( or that experts labeled the music (Pandora), the users may rate the playlist higher than it would under neutral conditions. Also, user should know little about the bands, which is difficult to ensure. Finding an unknown jam band might be difficult to accomplish for that frat guy sitting in class with an old set of Bercinstocks, Grateful Dead T-shirt, and messed-up hair.

This is not to say that previous approaches to compare playlists are worthless - it's just that they need to be considered knowing all the above factors.

Tuesday, May 19, 2009

Pandora's Profit

Wired had a little blurb about Pandora finally turning a profit in 2010. This can be attributed to many things, such as the growing fan base, the iPhone application, and the addition of commercials. What's more interesting is that Pandora is essentially becoming the same thing as radio in doing so with a small quirk. First, the addition of audio commercials was a major step, not just in the profitability, but also in the precedent. If viewers continue to listen, it's very likely ads will increase in frequency. It appears that listeners are not against advertisements in general, but no one has come up with a limit before users turn away en mass.

Also, the iPhone application is essentially the same in functionality as a personal portable radio. The only real difference is that you are streaming radio from the web to your phone. However, you have marginal control over the content. Yes, you pick the artist and you can assign "thumbs up" and "thumbs down," but I would not say that this radio is truly personal. You have no direct control on novelty, artist frequency, repeats, etc.

I think what has worked best for Pandora is the perceived personalization. Essentially, users do not want to be dictated listening habits. There's also an inherit confirmation bias in any recommender system. I'll remember the hits and forget the misses or explain it away. Also, people tend to respond positively when someone says, "you'll like this." It's incredibly hard to come up with a controled test to measure effectiveness. Some researchers have tried, such as comparing lists of recommendations and asking which is man-made or machine-made. However, the goal of a recommendation engine is to build the one with the best recommendations, not to mimick humans. At best, we can compare how two engines perform by comparing the number of skips.

For example, we could compare Pandora and in a large-scale listening test. Again, we need controls. Pandora and differ in the amount of perceived control. Both Pandora and do not give a lot of control on how music is played, but allows more feedback. Both Pandora and have access to a positive/negative vote for each song and initial seed song selection. However, also allows for tagging individual songs in an effort to improve selection. Of course, this is legitiatimate; however, a real test would let users tag songs for Pandora, but then Pandora would just ignore the tags. In addition, users need to be blinded on how the process works. It's not a fair comparison if someone tells you that a system is based on machine interpretations of expert or wisdom-of-the-crowd ratings.

I'm glad that Internet radio stations that thrive on "personalized" recommendations are beginning to make a profit. However, it's a bit early to say that a new dawn of music has emerged. Promising, absolutely; but more research is needed.

Best PhD comic ever

Hilarious, yet so true.

Saturday, May 16, 2009

Jenny McCarthy Is a Plague

A good friend of mine recently had twins. He now has to tell one of his in-laws that they are no longer welcome to their house because they refused to get their kids vaccinated. Why? Because Jenny McCarthy became an expert because... um...

Anyway, here's to you, McCarthy and your ever increasing body count.

Tuesday, May 12, 2009

Naked CIO surprisingly low-tech

I'm busy getting ready for the ISMIR deadline, but it was extended so I can take a few minutes to write. Yesterday, the Naked CIO posted an anti-social networking column. To his credit, he says that he likes increased social connectivity; however, this could be similar to when a Creationist says they are not religious and then spend the next few paragraphs arguing for the existance of a designer. The Naked CIO's main problem is how social networking sites, like Twitter and Facebook, will impact the work place (Note: I'm on Twitter now). Simple: people will learn how to use the technology.

I have a few problems with some specific arguments he makes. He starts by stating that email and instant messenging have blurred the line between formal communication between discussions on work-related matters and regular social interaction. One problem with this argument is his hidden premise that formality is more productive and healthy to the work environment. In reality, there are plenty of reasons to believe this is not true. Email, local wikis, and instant messenging have allowed for a lot of wasteful formal structures to be eliminated. It is no longer necessary to have a formal board meeting on every topic. I'm reminded of my first job out of college as a great example. The organizer started the meeting by saying that we had a meeting next month to plan a project and he wanted to get together to plan for the meeting. I'm not kidding. After 5 minutes I got up and left. He sent someone after to me when I didn't return and asked what I was doing. I had set up a project mailing list with an archive. Second, it is not fair to say that email and other technologies are the reason for decreased formality. Formality may have degraded for the simple reason that it is not necessary for increased productivity and can even become a negative by wasting time and making people remain silent because it would be rude to speak. As an example, overall attire has progressively moved from a coat and tie environment to khakis and polo shirts as the social norm. Why? Comfort.

He then goes through some scenarios that he feels may impact businesses. Here are the problems and my solutions:

1) Is a tweet from a company executive an official statement? Response: Depends. It's called a disclaimer. Columnists use this all the time so that the media outlet is not held responsible for opinion.

2) What if a friend mentions the possibility of layoffs on a social networking site and that negatively impacts the company, even if there are no layoffs coming? Response: Yes, new technologies make our jobs easier, even the job of being stupid. Social networking sites make it easier for young women to become targets of pediophiles, but it does not change the problem that teenagers are irresponsible and nieve. Most social networking sites have an option to send a private message versus posting to the known universe. The non-digital anology would be something like this: imagine you are sitting at a coffee shop near Wall Street with a friend. You are talking about potential layoffs with your company and you know this is sensitive information. You can either whisper it quitely or yell at him through a bullhorn. Yes, there might be an occasional idiot that unknowningly betrays his company, but there are idiots everywhere. We should not stop progressing as a culture because idiots cannot take care of themselves.

3) How do we resolve the issue of privacy when people can "Google" one another. Is it right for a company to do this type of background check on a potential employee? Reply: Is it right for a potential employee to lie or withhold information that may negatively impact his ability to work? Why should companies assume that everyone who applies for a job is trustworthy? People lie on resumes. People lie in interviews. Here's an example: an interviewer asks a candidate "What's your biggest weakness?" The candidate pauses, glances to the side, and replies, "Probably that I work to hard." Seriously? That's your weakness? The Naked CIO uses his brother as an example and questions what would happen if a company saw that his brother is a musician. Well, if he tours a lot and will miss work, then I fault your brother for withholding that information. The company should know if he's going to be missing work to tour or at least, be tired all day because he's playing music at a local club until 2 AM. Companies should know if you have another job. Heck, it's probably illegal not to tell them if you have to sign a disclosure agreement and your other job or hobby is in a related area. If your brother is an amature and maybe only has a couple gigs a month, your company will not care. Hell, it's better than what 90% of men do, which is sit on the couch and drink beer while watching football.

I'll never understand these nostalogic "those kids today" thoughts. Society evolves as technology evolves. You either learn to use it or end up complaining about the good ole' days.

Tuesday, May 5, 2009

Doggie Pseudoscience

I recently got an email about the frequency of washing my dog from the kennel where I board my dog, Marley. Needless to say, the brought in some naturalist veterinarian, to recommend shampoos and gave the standard crap advice. I'll forgo my rant on the obvious appeal to nature logical fallacy and go to my response to their call to avoid "chemicals." Here is the letter:

Dear Wag-A-Lot,

In your recent e-letter, you mentioned an article about the proper frequency we should wash our dog. In addition, you mentioned that we should use natural shampoos and "avoid artificially produced shampoos that contain chemicals as their major ingredients." I have had a hard time finding a shampoo that fits your description. The problem is that every natural or artificial shampoo has some form of chemical as a major ingredient. For example, most shampoos, such as the ones you mentioned (Spa and Earthbath), contain water, which is a chemical. Specifically, this is a molecule and all molecules are chemicals, so I originally filtered the list to only elements. However, I then did a little more research and found out that elements are also chemicals! In fact, since chemistry is the study of matter and its interactions with other matter, a chemical substance is any piece of matter which can be described by an empirical formula which expresses the relative numbers of each type of atom in it. Since finding this out, I have tried various forms of energy to clean my dog. First, I tried radiant energy in the form of light. I tried several types of lights from strobe lights to flashlights at various intensities, but this just seemed to make my dog excited and not any cleaner. I could try other forms such as X-rays, but I am not sure of places that offer X-ray dog cleaning. Do you know of any? Next, I tried potential energy by balancing my dog on top of a tall ledge. Not only did my dog stay filthy, but he also seemed rather uncomfortable. Fortunately, my dog was in a perfect setup to try the next form of energy - kinetic energy. Let's just say that the fall made my dog leery of going near me and he was actually dirtier.

Magnetism was my next energy type to try. After giving my dog a few treats so he would trust me again, I waved kitchen magnets over him. Maybe they are not strong enough to clean effectively. Can you suggest some effective magnets that might help clean my dog? He's getting very filthy and annoyed. In the meantime, maybe you can suggest some improvements on some other approaches. Heat - how long and hot do I need to cook my dog? Also, I never thought of hot dogs as being particularly clean. Electricity - I'm not a fan of shocking my dog, but if you guys know of an effective voltage and amperage I'll try it. I am an electrical engineer by trade and I feel I can administer this effectively on my own. Nuclear - are there nuclear power companies that offer dog cleaning? The ones I've contacted thought I was crazy.

I realize that I could also maybe try dark matter and dark energy, but if I'm not mistaken, scientists are still trying to detect these and there have been no attempts to harness them or put them into a dog shampoo. Please, let me know of any advice you can give me. My neighbors are complaining about my dogs stench and his howling over my treatments.