Ya, you caught me, (SI lurker extraordinaire). Do not do much posting but maybe I will get more time for such in the coming months. Will probably have to join here...right now I am a freebee.
-- earlier this week, I saw an opening trin of 42 (on the Naz) on Yahoo, but I must assume that was a "misprint" of a kind. Did anyone else see such an outrageous number? Sometimes Yahoo is not very good in reporting these number --
Yahoo isn't really "reporting" the number. I had assumed without thinking about it that there was "one" number and an official source, like the exchanges. But the exchanges are only providing the stock prices, volume, and the indices. Any indicators are being calculated by either the data vendors, which there are many of or the source you are getting the number from. Any charts you are looking at come from your chart provider, and their accuracy depends on what charting analysis software they use and the quality of their data. The data provided by the exchanges is known to have bad data in it, and it is up to the data vendors to "scrub" it. I found an interesting white paper on the subject, which I haven't had time to finish reading yet, #msg-2601329. How the data vendors go about scrubbing the data of course can affect the indicators you calculate from the data. And as far as using the same source, such as Yahoo, do they ever switch data vendors? Do their data vendors change how they scrub the data. Does the charting software get changed or modified? There's no simple answer to, are the numbers right?
The other thing to note is this month or maybe next Nasdaq is adjusting how they are calculating the opening and closing prices to make them more "accurate". One of the things they are trying to "fix" or prevent is the 30 sec jams at the EOD to "fudge" the numbers.
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