Just how reliable is backtesting?

Discussion in 'Trading' started by nxt7, Apr 14, 2016.

  1. kut2k2

    kut2k2

    Are you saying that even a little bit of lag in one of your systems kills its profitability?
     
    #71     Apr 17, 2016
  2. d08

    d08

    It obviously lowers profitability considerably but it doesn't completely kill it. I'm saying that when conditions for a system are not favorable, it will lose very little or flatline the equity but that's alright because it outperforms when the conditions are right.
     
    #72     Apr 17, 2016
    kut2k2 likes this.
  3. That's why trying to know when markets are trending or not is the most important, but also the most difficult, part of building a system. If you know when markets are trending, or not, you have already achieved the biggest part of the job. That part will be responsable for the major part of the performance. Building the rest will be much easier as it is only timing of entries and exits.
     
    #73     Apr 17, 2016
    dartmus and kut2k2 like this.
  4. I totally agree....especially this:"The system should be adaptive". For example, it needs to adjust for volatility. Small range bound conditions can really prove to be challenging.
     
    #74     Apr 19, 2016
  5. userque

    userque

    Yes, the system runs optimizations (adapts) internally. I don't manually optimize it daily. As that seems to matter to some here.

    To be simpler: As many have pointed out, there is chop, there is trend, there is flat. A system that optimizes daily can adjust on a dime to such market conditions.

    Also, it is based on an extremely customized kNN type algorithm that also utilizes machine learning ensemble methods.
     
    #75     Apr 19, 2016
  6. Buy1Sell2

    Buy1Sell2

    Backtesting lends itself to curve fitting. This is a weakness that most traders have.
     
    #76     Apr 19, 2016
  7. Buy1Sell2

    Buy1Sell2

    Best bet is to get in and trade. Your losses are called tuition. If not able top turn a profit in 6 months, it's best to try your hand ta something else.
     
    #77     Apr 19, 2016
  8. Buy1Sell2

    Buy1Sell2

    Forward testing is the only thing of any value in the learning process.
     
    #78     Apr 19, 2016
  9. Buy1Sell2

    Buy1Sell2

    Lose real money in the real market. That beats backtesting every trip of the train.
     
    #79     Apr 19, 2016
  10. And if it works in foresight too, you have an edge.
     
    #80     Apr 19, 2016