RSI at finance.yahoo.com

Discussion in 'Technical Analysis' started by vayu, Sep 4, 2013.

  1. vayu

    vayu

    I found that RSI indicator available at finance.yahoo.com does not match to the standard RSI.

    For example, according to both NinjaTrader and Ameritrade, Boeing Company (BA) on 8/30/13 had RSI(10)=45.88.

    On the other hand yahoo finance shows RSI(10) = 52.58, it's quite different.

    Does anybody know how yahoo finance work? I found their version more interested than the standard RSI.
     
  2. kut2k2

    kut2k2

    You've discovered a dirty little secret of TA: virtually every indicator formula is posted wrong somewhere.

    A widespread example is the MACD. When Gerald Appell first published it, he recommended two parameter sets: 8,17,9 and 12,25,9. Somewhere along the way 12,25,9 got typoed into 12,26,9 and this typo has been copied and pasted so much, it is now more widely distributed than the correct original parameter set.

    I had MetaStock in the 90s and it was full of incorrect indicator formulae. Always verify what the book or sw vendor is telling you.
     
  3. Did you verify that they all use the exact same, correct, closing prices for BA? RSI is path-dependent. GIGO.
     
  4. vayu

    vayu

    Sure, closing prices are exactly the same.
     
  5. moonmist

    moonmist

    You may like to check the following:

    a) The original formula of RSI involves Wilder moving average (WMA) . Newer version of RSI may employ exponential moving average (EMA). Make sure all of them are using either 10-period WMA or 10-period EMA.

    b) Most people use closing price to calculate RSI. However, some may use typical price, OHLC/4, etc. Make sure that all of them are using the same "price".

    c) For RSI to converge, at least the last "3 x period of EMA" bars should have the same closing price, typical price, etc. Make sure that this is true. For a 10-period WMA, the last 57 bars should be identical.

    Good luck.:p
     
  6. Why are the exact parameters so sacred? Can't we think outside the box?

    The originating post showed concern about whether the "real" level was in the forty's or fifty's. Obviously ,it was the 50% level signal behind the concern.

    I ask ... why? Take a look at the chart. Take a GOOD look. Am I the only one in the world who thinks that the real value of the RSI is not in it's level ... but in its DIRECTION?
     
  7. kiev

    kiev

    I noticed same thing 1 year ago, after I did some math, I found yahoo is right, they just calculate rsi in different way. And for some stocks, the close prices are different from IB.
     
  8. RSI values depend on the starting point because of the exponential MAs. If you allow enough time on a chart the values will converge. Usually about a year.
     
  9. Stop using indicators.