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Subject:  Re: Bear catchers Date:  2/23/2013  1:11 PM
Author:  mungofitch Number:  241838 of 270533

Would it yield better results to use a simple MA crossover for example (to avoid big losses)
on each security? Or would it perhaps cut gains and decrease overall profit without limiting risk?

As far as I know, nobody on this board has found a TA-like individual security stop
loss strategy that is both backtestable and passes the backtest.

The problem is that markets are squiggly, and often lots of things dip at the same time.
You want to sell an individual security not when it dips, as everything
might be dipping, but rather when it stops underperforming its peers.
Just a general comment on why momentum tends to work but stop losses tend
not to work with the type of stock selection methods we use here.

If you think about it, a momentum final-sort screen is a stop loss, but the stop
is when the loss relative to peers is a certain size, not in absolute terms.

One can only answer your question as the answers to the backtests that
have been done (market-wide timing tends to work and stop losses
tend not to work with the sorts of investments we're doing), and
with general speculations as to why that might be.
I guess we can't answer absolutely, as there may be many strategies
for purchasing and holding under specific circumstances, for which
stop losses do add a lot of value. I don't know 'em, all I can say is
that they aren't the strategies that are used and tested here.

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