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Incorrect price data on CDII?

Doing a backtest I stumbled into a security called "CDII" which has a very weird price change between 2008-09-19 and 2008-09-22, moving from 0.05 to 5.51 (interpreted as a huge gain on that day, see attached backtest). I looked at yahoo and other sources and while it looks like an extremely volatile security that is basically worth nothing today, but back in 2008 it had some value. I'm wondering if there was a split those days that was not correctly documented in the quantopian system?

Thanks

Karol

4 responses

There is something crazy about that stock for sure. I think it got delisted from NASDAQ and went OTC in 2012, and there isn't a great historical record of it. Morningstar's data isn't right either. eTrade shows a 100:1 split for that day, but none of the regular split tracking records show it. We have an open bug on this one, but it's not resolved.

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The material on this website is provided for informational purposes only and does not constitute an offer to sell, a solicitation to buy, or a recommendation or endorsement for any security or strategy, nor does it constitute an offer to provide investment advisory services by Quantopian. In addition, the material offers no opinion with respect to the suitability of any security or specific investment. No information contained herein should be regarded as a suggestion to engage in or refrain from any investment-related course of action as none of Quantopian nor any of its affiliates is undertaking to provide investment advice, act as an adviser to any plan or entity subject to the Employee Retirement Income Security Act of 1974, as amended, individual retirement account or individual retirement annuity, or give advice in a fiduciary capacity with respect to the materials presented herein. If you are an individual retirement or other investor, contact your financial advisor or other fiduciary unrelated to Quantopian about whether any given investment idea, strategy, product or service described herein may be appropriate for your circumstances. All investments involve risk, including loss of principal. Quantopian makes no guarantees as to the accuracy or completeness of the views expressed in the website. The views are subject to change, and may have become unreliable for various reasons, including changes in market conditions or economic circumstances.

Thanks for looking into it, I'll just ignore the security for now.

And now that we're talking about delisted securities.. I just spent some hours decoding what was wrong with other algo that kept increasing leverage as it was aging even though the logic implied that wasn't possible. It turns out that if you buy securities that were delisted, you can't sell them after the date when the security was delisted (which I guess makes some sense, but you may argue that an investor could still use OTC in certain circumstances).

Therefore algos that incidentally buy such securities (using some method like fundamentals, which doesn't use the sid() protection) will never be able to sell them after the date it was delisted, accumulate several of these and your leverage increases over time. Not sure if there's a workaround about this.

@Karol, handling delisted securities in the algo is tough since there can be a number of different outcomes. In the meantime, try this workaround that Seong shared.

Disclaimer

The material on this website is provided for informational purposes only and does not constitute an offer to sell, a solicitation to buy, or a recommendation or endorsement for any security or strategy, nor does it constitute an offer to provide investment advisory services by Quantopian. In addition, the material offers no opinion with respect to the suitability of any security or specific investment. No information contained herein should be regarded as a suggestion to engage in or refrain from any investment-related course of action as none of Quantopian nor any of its affiliates is undertaking to provide investment advice, act as an adviser to any plan or entity subject to the Employee Retirement Income Security Act of 1974, as amended, individual retirement account or individual retirement annuity, or give advice in a fiduciary capacity with respect to the materials presented herein. If you are an individual retirement or other investor, contact your financial advisor or other fiduciary unrelated to Quantopian about whether any given investment idea, strategy, product or service described herein may be appropriate for your circumstances. All investments involve risk, including loss of principal. Quantopian makes no guarantees as to the accuracy or completeness of the views expressed in the website. The views are subject to change, and may have become unreliable for various reasons, including changes in market conditions or economic circumstances.