What

First and foremost, this is an unproven method of choosing when to enter and exit a position. Since back-testing is used to produce the models future results may not reflect or produce expected returns.

2014-05-13

What Happens When A Correlated Symbol Is Dropped

This morning when running the models I noticed one symbol "LSI" was not returning current historical data from Yahoo Quotes.  It turns out that  LSI was purchased by AVGO and the LSI symbol is no longer active.

My first thought that was since LSI was one of 20 symbols that a model may be suing and that it was no longer available the other 19 would "cover" for the missing data.  But that wasn't the case as the buy/sell indicators and the date of the occurance change.  To make matters worse it turns out LSI was used in all 10 models.

So I changed LSI with AVGO and the ran the models.  The run results were completely different when compared to when LSI was not used - again I assumed one symbol couldn't have had that much affect on the over model but it does.

So I looked for a symbol whose stock price correlated the closest with LSI and it was FDO.  FDO is already used in only one model BIBs.  Running the models with FDO produced results similar to yesterday's so I will not be rebuilding the models from scratch.

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