hfttrader

Not everyone has a phone, or a phone supporting NFC. (Microsoft employs >100,000 people) Badges are a low cost solution which don't require charging and can be easily issued or replaced. Additionally, badges display pictures, so people wandering around the office can be visually checked by security. (No need to scan their badge)

Traders are not necessarily smarter than the average software engineer. (There are many very smart people in both fields) However, they are fairly irreplaceable. This is because to be good at finance you need to be both smart and experienced. The only way to get experience is to work in finance for several years, and as a result, the supply of traders is fairly limited. (compared to the demand) Generally, someone who starts finance will not make their firm any money for the first year, but after five years they will be earning their firm a lot of money. The supply of good traders is a lot smaller than the supply of smart people.

A second reason why they are compensated so highly is that they are working in a highly leveraged job where the labor cannot be easily be divided between multiple people. This is similar to how CEO's make a lot of money, because being a good CEO produces a lot of value for the company and the position cannot be split between multiple people. (I'm not trying to imply that traders produce as much value to society as CEO's do) Being a marginally better trader will make your firm millions more per year. Good hedge funds have 100-1000 million of assets under management per front-office employee. (For example, D.E. Shaw or Bridgewater Associates)

But why does transferring large amounts of dollars take days? There is nothing physical preventing banks from supporting fast transfers. They can do fast transfers with BTC or USD.

Transfers are slow because there is little need to transfer large amounts of money quickly, and slower transactions help address issues with fraud. If you are buying a car, or paying for a house there is little need for a fast transactions. So with BTC or USD, transferring large amounts of money will take days.

Why are the other people creating value, while HFT traders do not? Both types of players extract value from the market, while improving market efficiency.

HFT definitely has high entry costs (10's of millions of dollars), and firms that aren't serious about HFT can't participate. Note that HFT only makes 2 billion a year, so they aren't actually missing out on that much. HFT just isn't a very big space, compared to long term investing, and doesn't represent very much movement of capital. (The wealthy don't really invest in HFT, since HFT firms generally don't accept outside capital, or need any substantial amount of capital to operate)

This article is talking about internally transparent salaries. The salaries aren't disclosed to outside parties, so the policy doesn't help poachers.

Generally, HFT firms end up decreasing volatility. They price stock more accurately, which makes them money and decreases volatility. If they were increasing volatility, they would make infinite money, since the source of their profit is the volatility.

The main scenario where HFT firms increase volatility is when their algorithms break (either due to a programming error, or because they cease to accurately model the market due to a change in market conditions). In that case, the misfiring algorithm will increase the market volatility, and lose the HFT firm money.

You absolutely right that firms without co-located data centers are at a disadvantage. Thankfully, this only really matters if you are trying to compete with HFT firms. So it's not a big issue for people who trade on a longer time scales. The HFT firms do make some money off of these long term investors, and in exchange provide increased liquidity, decreased spreads, and decreased volatility. (if the HFT firms weren't offering the best prices for the stocks, then the long term investors wouldn't be buying from them)

That isn't really an example of market manipulation. Market manipulation is an intentional manipulation of the market. (http://en.wikipedia.org/wiki/Market_manipulation) The Knight Capital incident was an example of a firm performing bad trades due to an error in their systems. Their behavior certainly wasn't intentional or profitable.

HFT isn't based on market manipulation. Some HFT firms perform market manipulation, as do some non HFT firms, but this practice is illegal. (For example, newedge was recently fined for market manipulation)