Quote from ivanbaj:
Can you propose how a price/time chart would look for a stock where the big majority (80-90%) of the traders are insiders?
If the majority of traders in a stock were insiders then any information that could cause a price shock would be reflected as soon as the insiders knew (ie the stock would not move when the price shock news was later publicly released the stock. A stock with this much insider trading would be from a trading perspective equivalent to a stock with no insider trading as any price shock could not be predictable from prior prices.
Do you assume that all insiders act on the same knowledge?
Do you assume that all insiders get the knowledge at the same time?
No, but none of these matter in regards to insider trading causing price predictive information to become embedded in the price data series.
Do you assume that all insiders will act on the knowledge at the same time? Can you accept that some insiders will act sooner than others?
This doesn't matter. If some insiders act after others then the difference will just be a lag in the price signal rather than a spike.
Is it possible that some of the insiders might be involved in creating the knowledge?
I would expect so. This is rather irrelevant to trading though.
Is it possible that some insiders might not buy into the knowledge 100% and have some doubts?
The insiders I am talking about are not those that have the knowledge, but those that trade on that knowledge. If an insider choose to not trade then apart from not being a crook, they will have no affect of the market.
Do you assume that all insiders have the same goals?
Do you assume that all insiders have the same levels of greed and fear levels?
I do assume that all insiders that chose to trade on this knowledge have the goal of making a profit. If insiders choose to trade at a level below the possibility that the information provides then the end result will be that the price predictive signal will be present, but smaller.
Will the bigger insiders make their purchases at once moving the price to a new level, or will they try to get as much of the purchase on a lower level by making smaller purchases over some time?
This doesn't matter, the effect of slow buying verses fast buying would be to just slow the price movement direction. The end level will be the same all things being equal.
Can you accept that some of the insiders will start faking their intentions? Selling when they intend to buy?
Yes insiders could do this, but this is also a price signal
It seems to me that stocks traded mostly by insiders will show some level of noise that we as traders will need to interpret and bet on.
This is exactly my point. Most price movement is noise, the question is identifying those stocks where past price movement is predictive of future price movement. My prediction, based on the random trading hypothesis, is that the price predictive signal present in the past price data will be the largest in those stocks that have the greatest amount of insider trading. Since it is possible to retrospectively identify those stocks with high levels of insider trading, and assuming that stocks that have previously had high levels of insider trading will have high levels of insider trading in the future (a fairly reasonable assumption), then this prediction should allow you to know where to concentrate your trading - ie use a follow the crooks strategy.