For anyone interested in the potential reasons: one of the most posited ones is that the creators of the tests are inherently biased. i.e. if someone creating an IQ test is a white male, chances are white males will have an advantage on the test.
This has some degree of experimental evidence behind it, I remember in one of my psych classes we learned about a study where test creators tried to create tests [and succeeded] where certain races or locales would score higher [primarily by having people in those places or people of that race create the tests]. It's very hard to create a "general intelligence" test that isn't biased in some fashion [and many say it's impossible]
If the blockchain is useful in those areas where [almost] no trust exists, Urbit has the potential to be useful for essentially everything else.
To give a concrete example, this would be useful for any Ethereum app that doesn't want to store data on a central server (which most cannot do whether for legal, security, or ideological reasons). The idea to me is that the internet wasn't built very well to run decentralized apps [which is definitely the case if you've ever tried building one without having to rely on central servers for caching, storing accounts, comments, etc.]. It's, imo, a nice complement to blockchain tech like Ethereum and Bitcoin. Long term once it's out and running I see dapps like Augur [a decentralized prediction market which I work on - http://augur.net] using it so users can securely store their private keys, report data, market data, trade history, etc. and easily go across/between devices as opposed to just using localstorage [which is a pain to migrate using] or fetching it from ethereum every time [which is very time consuming and has lots of overhead].
If we're going to seriously move in this direction of decentralization, at scale we need something like urbit.
No one else is really tackling the same set of problems.
Came across this quote on it by Alan Kay: "They have verve, and that's generally a good thing. In this case there are a lot of details that need to be grokked to make any reasonable comment. The use of combinators (a kind of dual of lambda calculus) harks back to an excellent thesis by Denis Seror at the University of Utah in the 70s that produced a safe, highly scalable and parallel implementation. I haven't looked at it more deeply (and probably should)." [https://news.ycombinator.com/item?id=11810177] - very cool!
There is no such thing as a trustless app, unless you are doing basic mathematical algorithms contained within the same system. Ethereum adds no value to Bitcoin because any useful apps you want to make NEED a centralize source to provide data to it. For example, if I want to make an app that sends coins to someone when bitcoin is at a certain price, I would inherently be relying on the trusted source, that provides the bitcoin price data. Similarly for sport payouts or property contracts, they all rely on the external centralized source for information. The only thing Ethereum can do, is basic operations contingent on values within the same system, otherwise you break the "trustless apps" veil.
Reread my post, I said almost. Nothing in life is trustless [for instance, solar flares could effect my computer's state], but you can get close. So we agree there
> Ethereum adds no value to Bitcoin because any useful apps you want to make NEED a centralize source to provide data to it.
This is called the oracle problem --- it's a difficult problem, but not intractable. Augur doesn't use a centralized source to resolve its markets, it has groups of reporters who do that [with a whole set of incentive structures surrounding truth-as-schelling-point and relying upon bonds to cause monetary loss to people attempting to "cheat" the system. Your cost to cheat the system will almost always be more than potential profit [unless there's only 1 market in a system with a ton of volume and no other activity, which means it's basically dead anyway and there are 2 backstop mechanisms surrounding this as well]. Anyway given infinite money anything is attackable / not trustless.
Second, you're missing _a lot_ of the benefits of Ethereum. It can control funds programmatically. To run a prediction market using bitcoin you have to hold customer funds, on Ethereum you don't [this is a huge opex]. On Bitcoin, you have to process the trades, on Ethereum you don't [hello more opex!]. On bitcoin you're forced to use a multisig 3rd party or have counterparty risk to trade prediction market assets, on Ethereum you don't. You have to resolve markets yourself [or with multisig of a handful of people, because bitcoin cannot support multisigs beyond 20]. People can't create their own markets and add liquidity to them on your platform if it's on bitcoin without trusting you either. Could go on and on, but _unless_ you're referring to a sidechain of bitcoin you can't do any of that.
As far as the example here: "For example, if I want to make an app that sends coins to someone when bitcoin is at a certain price, I would inherently be relying on the trusted source, that provides the bitcoin price data." is wrong. On Etherex on ethereum I can get data for he btc-eth price and do a transaction based on the exchange rate without trusting anything in the outside world
One example of an app you'd want to run on ethereum is something like a prediction market (PM). A PM is a pretty general financial market and can be used to speculate on things from "Who will become the US President in 2016?" to "Will Russia invade Estonia by 2020?" to "Will American Pharoah win the Triple Crown?"
Ethereum is useful for this because it allows for distributed custody of funds. No one controls the funds stored in these contracts, so there's no one to run away with and steal all the money, and, since it's run on Ethereum, there's no middleman taking 5-10% fees. In fact, for the first time, we can have a truly global prediction market, and _anyone_ can create markets on it to boot! This is just one app possible on ethereum, and it's one I'm building - www.augur.net if you're interested.
Ethereum's basically a platform that allows you to create "smart contracts" (aka programs) that are practically guaranteed to execute the way you write them. And multiple people can interact with the programs and it'll still be executed the same way. This is a bit abstract, but the main huge advantage this allows is: you can finally send money to some program, and the program will do exactly what it says it will, and no one else can modify the results or even touch your money. Bitcoin allows you to send money around, Ethereum allows you to enter into complex contracts with money, and those contracts are always enforceable.
To take this into the real world, imagine you want to make a bitcoin prediction market. Since you can't run the complicated buy/sell machinery of a prediction market directly on bitcoin, you're forced to take deposits from users, match their orders, and then do payouts accordingly after the event occurs. You can run away with the funds at any time, and there's nothing stopping you. Sure, you could elect to use multisignature wallets or cold storage, but that didn't stop MtGox from happening. Heck, even InTrade, the largest prior prediction market had millions of dollars of funds embezzled by their later CEO.
Now with Ethereum, we can send funds to a contract, they're stored there. You can buy and sell and all orders go through the contract. At the end payouts are done by the code in the contract, and no one can take the funds held in the contract.
Augur allows you to create any sort of predictive marketplace without counterparty risk. It utilizes Ethereum for its smart contracts and Bitcoin as a currency
In events without a clear outcome (say greater than 65% certainty, this is a tunable parameter) there's an audit system where a different group of reporters is asked to answer the question. The idea is that they'd notice the extreme multimodality of the last group who reported on it, and in self interest of preserving their reputation, report an "invalid" outcome.
Sybil attacks are addressed due to the way reputation works. Reports are a weighted average - so the more reputation you have, the more your votes are weighted. You could make a billion separate accounts and send them each one reputation, but there's no discernible difference than if you had just reported with one account with one billion reputation.
For anyone interested in the potential reasons: one of the most posited ones is that the creators of the tests are inherently biased. i.e. if someone creating an IQ test is a white male, chances are white males will have an advantage on the test.
This has some degree of experimental evidence behind it, I remember in one of my psych classes we learned about a study where test creators tried to create tests [and succeeded] where certain races or locales would score higher [primarily by having people in those places or people of that race create the tests]. It's very hard to create a "general intelligence" test that isn't biased in some fashion [and many say it's impossible]