Experimental Computational Philosophy: shedding new lights on (old) philosophical debates

Vincent Wiegel presented joint work with Jan van den Berg investigating a criticism of a philosophical standpoint called act utilitarianism (contrasted to rule utilitarianism).

Roughly speaking, an act utilitarian evaluates each action, as they occur, in order to decide the utility of acting while a rule utilitarian acts according to a general rule about the utility. The thought experiment used to debunk act utilitarianism was that of an election. In a population of 100 an act utilitarian only votes if they are the 51st person to vote for their preferred candidate in all other situations they gain more utility by going and doing something else more interesting. Wiegel and van den Berg simulated this situation computationally. Obviously first they had some issues about why an act utilitarian might conclude they get utility only by being the 51st person to vote and of course, how they might determine that they have the deciding vote. Interestingly, when they varied their assumptions a bit so that act utilitarians only voted if they had reason to believe they were in the range of the 46th - 56th voter (or similar) - i.e., that their vote was likely to decisive then they did very well frequently getting the outcome they wished in an election while getting to do other more interesting things when the outcome was essentially a foregone conclusion anyway.

Doctor Who: Partners in Crime

I liked this. I'm not sure I have a great deal to add beyond that. My favourite bit was the scene between Donna and her grandfather in the allotment - to be honest right up until the moment Donna went all dreamy eyed about travelling between the stars. It occurs to me that there are a lot of these speeches sprinkled through NuWho and they only occasionally work because, frankly, they are just not the sort of thing people say and they break the down-to-earthness it strives for in its contemporary characters.

We missed the very start of the episode so I was a little unclear on the set-up. Was it ever made clear that Adipose (aside for the issues of consent and the fact they were killing folk that witnessed them) were harming their victims? The story came close towards the end to pointing out that these were not straightforward villains but didn't seem to have quite the courage to say so. But it was a clever counterpoint to the Runaway Bride to make this story also about alien children. My jury, I must admit, is still out on Donna. I can see how they've tried to mellow the character a bit but the end result was a little schizophrenic as if they weren't quite sure how to make her challenge the Doctor while at the same time wanting to travel with him. Hopefully this will settle down as the series progresses and once he has no choice but to have her with him.

Private Information and Inference about Inference

Sobei H. Oda (together with co-authors, Gen Masumoto and Hiroyasu Yoneda) had been simulating the (I think) Future's market. In particular he had been testing the hypothesis that you make more money if you have better information about the future price of a commodity. He had a graph that showed the people with no information doing a little better than those with just a little information. The people with lots of information still did best. He had some maths to explain this, which it must be said I didn't follow, but I thought it was an interesting effect.

Sleeping with Fear

I put Sleeping with Fear by Kay Hooper on my Amazon Wish List after reading one of neadods's pieces on Reviewing the Evidence and was duly given it for Christmas. Riley Crane, a Clairvoyant member of the FBI Special Crimes Unit, wakes up one morning covered in blood, with no memory of the past three weeks and, apparently, without her powers. The book follows her efforts both to discover what has happened to her and to solve a gruesome murder. I thoroughly enjoyed this. It does pretty much exactly what it says on the tin, i.e., it is a supernatural detective story - nothing more and nothing less, but it does it very competently. I can nit pick, but I won't because if you look hard enough at almost anything you can nit pick. Riley is an attractive heroine and, although she does stupid things, is aware of the fact and there are good reasons why she does them even though that's not always obvious at the time.

There are, apparently, several Special Crimes Unit books so I shall be checking out the others. In fact Amazon informs me that Sleeping with Fear is the third in the "Fear Trilogy". I'm guessing this trilogy is pretty loosely linked because I honestly had no idea. An unchallenging book but recommended none-the-less.

An Experimental Study of Information Mechanisms in the trust game

This is the last experimental game theory talk I'm going to precis - but it was a fascinating session and an area I'd not come across before.

This talk was by local man, Juergen Bracht. The "trust game" is one which involves an investor and an allocator. The investor starts with 2 points and can keep them or invest them. If (s)he invests them they automatically grow to 8 pts which the allocator can then either keep entirely for themselves or split between the investor and the allocator. Juegen was interested in the effects of two processes on the trust game. The first, "cheap talk", was where the allocator was allowed to tell the investor what they intended to do with the points in advance, but was not held to that utterance. The second, "observation", was where the investor had access to the allocator's previous actions.

Unsurprisingly, especially since the interaction was computer mediated, not face-to-face, cheap talk had little effect on investor or allocator actions. Less surprisingly observation did have an effect (except in the last round - where both investor and allocator knew it was the last round). The reason I say "less surprisingly" is became in pure game theoretic terms the reasoning goes: in the last round the allocator should keep all the points since no one will ever use the outcome of the round in an observation, therefore the investor should not invest their points. This being the case the second-to-last round is the last one where anyone will invest so the allocator should keep all the points since no one will ever use the outcome of the round in an observation, therefore the investor should not invest their points. This being the case... and so on so no one ever invests anything... Clearly classical game theory needs some rethinking if we expect it to realistically model human actions.

Resolutions Post

1. Find a way to get more exercise

I cycled to the station on monday. Exercise book disasters continue - my second is now lost in the post.

2. Drink/buy less alcohol.

Alcohol bought: 1 bottle wine - misc beer and whiskey in Aberdeen.
Alcohol opened: 2 bottles wine.

3. Do list of "before bed" actions pinned to fridge.

N/A

4. Write a grant.

No progress.

5. Write papers for ProMAS, ASE and TPHOLs.

ASE paper (only one remaining) to be submitted any day now.

6. Done.

7. Try a new recipe each week.

Potato cakes stuffed with lamb mince and pine nuts from Casa Moro pronounced a success but fiddly. Eventual verdict was that it will go in the book but only be used when we feel like making a particular effort to cook.

Addressing NP-Complete Puzzles with Monte-Carlo Methods

Maarten Schadd (with co-authors Mark Winands, Jaap van den Herik and Huib Aldewereld) gave a talk whose primary interest, from my POV, was that the bricks breaking game on Facebook is NP-Complete.

I'm going to have to explain that aren't I.

A P-time puzzle is one which, to all intents and purposes, can be solved quickly (according to a technical definition of quick). An NP-time puzzle is one in which, if you have the right answer, you can check it is right quickly but you can't necessarily find the right answer quickly. No one knows if P=NP though most people suspect not. Field medals will be won and a lot of research will get torn up if it turns out that P does equal NP.

I rather like bricks breaking.

Theory and Practice of Social Reasoning: Experiences with the iCat.

All I'm going to note about this talk is that I find the iCat more disturbing than cute.

I sat next to the speaker, Frank Dignum, at dinner that evening and, as well as being very nice, he said some very perspicacious things about organisations of agents which I'm going to have to think about.