Monday, September 24, 2007

First Week of Trading



Please note: I will be talking about strictly screen trading in this article. I know nothing about floor trading or the crazy symbols they use.

Trading is a major rush for me. Given how much fun I had, it is hard to believe that traders get paid (besides compensating for stress). Every trainee loves trading, but not all of us loved how low our P/Ls were on the first week. I lost a good deal of money, down about 700 (this is pretty consistent among the trainees).

I know many of you read this blog so I would finally get to the part where I talk about: what is trading like? I will split the below in as many perspectives as I have time to write.

Trading as Math
You do second grade math all the time. You need add / subtract quickly and consistently. The more difficult math (some of which may be found here) is for thinking at home and developing strategy. You are unlikely to use it throughout the day.

Often, you will want to recalculate the theoretical value of what you want to trade. You will need to instinctively be able to find the middle of the spread. Sometimes, you want to be in the middle of one and lifting the offer on another. That means the high end of the spread is worth entering the transaction for you, so you transact with the person and buy high. (Otherwise, you would join the bid, which basically means that you are willing to transact if someone wants to come sell to you)

Trading as a Game
Trading is just like playing a computer game, except your mom won't get upset if you play. Many of the concepts I apply get good at a real time strategy game, I am trying to apply to trading.

Knowledge
  1. Learn all the statistics - what is the correlation between futures price falling and vol going up; how much deviation is likely in each greek; what news affects the prices; how does it affect the price; etc.
  2. Understand your role in the game - what is your advantage (if you think you have one); how can you exploit your core competency fully?
  3. Weakness - once you understand your strength, you should understand how your strategy can be gamed; are you doing mental math fast enough, are you misreading what the market is saying
  4. Analogies - what is trading like? What do thinking or non thinking beings do to survive / thrive in these types of environments
  5. Next Steps, Frameworks, and Discussion - people have theories, learning them is good
I used to play a game called Rise of Nations. At a job interview, my interviewer told me his children played the same game. Since I was an expert in the game, he asked which nation I liked to play. The answer is that I play every nation on random. In a real game, every strategy has a weakness and telling your opponent anything, is too much.

Preferences
  1. Change screen content - the more you see the more you know, but also the more you slow down the computer
  2. Visualizations - a friend of mine wanted to switch the cursor icon to all black so that he could see it better, I changed the font size so that I could see more on the screen
  3. Window Placement - self explanatory
Speed and Consistency
  1. Hot key usage - you should know most of the hotkeys after week; there are hundreds of key combinations that can do the same thing; some will be easier at first but don't have the speed potential of others
  2. Mouse sensitivity - you should get used a mouse with a higher sensitivity (you can change this in the control panel)
  3. Mechanical Weakness - you will sell futures when you need to buy futures or hedge correctly but too slow; you will accidentally increase vol when you should decrease vol; you will enable your computer to do trades when you want to stop (these get less and less likely as I continue to list them).
  4. Hand Eye Coordination - Programs like EyeQ and THINKfast may help you improve your mechanical skills

Trading as a Psychological Experience
The market is risk-neutral. You will often face the market with less than perfect objectivity. You will probably lose upside potential due to fear. I will list some examples of each type of feeling. There will be times where you follow an example and you are not feeling any of these. There are always exceptions.
  • Fear / Nervousness - Example 1: Lets say you got a good deal on a call option that you bought for 2,15 when you thought it was worth 2,18. You are sitting with some greeks that could potentially move against you. The only way to hedge is to sell your call option. Some time passes and the market is willing to buy the option for 2,20 from you. You decide you will sell and just take your profits. Is this a good move? If you took the 'fear' header seriously then you probably know that I'm going to say not to do this. It is likely that the market wants to buy the option for 2,20 because it is worth a bit more than 2,20. This fear is very dangerous because it can be rationally justified (although poorly) with arguments due to mean reversion. Or even more poorly with the gamblers fallacy.
  • Greed - This is the exact opposite of fear. You are holding a position that you think is overvalued, but you think that the market might continue to pay you off due to some sort of momentum argument. Way back in your head you know that if you think something is overvalued, you should hedge it. When you are greedy though, you are likely to believe that you are smarter than everyone else and reject the signs that tell you to get out of a position.
  • Wishful thinking - You just lost a lot of money because a position that you were about to hedge swiftly moved against you. You decide you should wait because the market must return to its original levels and hedging now, for a loss, would be stupid. More often than not, this is just wishful thinking.
  • Frustration - You just lost a lot of money unexpectedly and someone is whistling a terrible rendition of Bach. Resist the urge to break things. It is unlikely that you will get violent , but you will have trouble making sound decisions.
  • Everyone has there own 'pet peeves.' Mine are vibrations that I can feel (especially my chair being touched, humming, tapping on the desk or by feet). It is a fact that it is impossible to live without making vibrations, and yet -- I don't like feeling other's vibrations. You might have an aversion to gum smacking. These things need to be communicated clearly and without malice if you hope to overcome this weakness as easily as possible. Combined with regular frustration, pet peeves can seriously debilitate your ability to perform at the highest level.
  • Happiness / Laziness - You just made a ton of money without even trying. You decide to sit back, relax, and stop trading.
  • Sadness - I just lost a lot of money. I am not going to trade any more today.

I went to the streets to see what the traders had to say about trading:
"awesome," said one. "fantabulous," said another. The average trader doesn't seem to like to talk all that much. The average wholesale trader -- that's another story.

Who would be good?
  • Strong self discipline
  • Consistent, quick mental math
  • Likes computer games
  • Likes chance games (most people do not like chance games)
  • Interested in finance
  • Can accept the risk of failure
  • Likes computer screens
  • Interested in making money
Answers to previous Math Finance Questions:
1) You own a stock. It exhibits 0% vol for 3 months and then 30% vol for the next three months. What's your average vol for the 6 months? (hint: variance is additive) I was surprised that no one answered this question correctly. Volatility is the square root of variance, so you have to square the volatility and then average to get the average variance. Then you have to take the square root to get the average vol. As the picture at the top of the post shows, vol is just another name for the standard deviation.
There are two reasons why I am stressing this:
  1. Everyone seems to be able to say "volatility grows at the square root of time," but can't prove it. Take year 1 vol = v, year 2 vol = v as well. Square both to get v^2 + v^2 = 2v^2 for the 2 year variance. Now just take the square root.
  2. Natenberg's treatment of volatility is poor relative to the rest of the book. He just averages volatility. Clearly, vol does not average.
2 and 3) I am going to wait until some more people try to answer these.

4) According to Hami: covariance is the measure of how the deviations of two variables match each other. Correlation is an adjusted measure of covariance when the variables have been standardized, or made comparable in magnitude and dispersion.
- Exactly, measures like Beta are Covariance. Statistical correlations of say, vol and futures, do not speak of magnitude (be careful!).

Math of Finance Questions: (I don't know the answers)
1) What is a good predictor of market spikiness? (This can be mathematical or non mathematical)
2) On what days do you expect larger market movements? Why?

Note: Do you like writing or even hearing yourself talk? Do you like finance, math, or trading? I am considering opening up this blog to a couple who want to write good stuff. Please email me at igor.schmertzler@gmail.com

Ps: If I have time, I will write about adverse selection.

3 comments:

ig0r said...

market "spikiness" tends to be a function of bid-ask spread and more importantly how much size is there. If size isnt willing to quote tight, theres probably a reason -- the next big liquidity taker may not have a problem with reaching a few levels.

Arvindh said...

hah! I remember your vibration peeve!

Igor said...

sorry to all of you who are waiting for a post. I have a pretty good one coming that I will try to get out between today or tomorrow.