Moving discussion of this issue here, at Regina's request. Hi Regina
> The function ZTEST should depend on NORMSDIST. >Therefore NORMSDIST has to be controlled and improved first. I'm afraid I disagree pretty whole heartedly :) NORMSDIST may or may not be more accurate in Excel, but in Calc it is accurate enough to use. For example for our 2nd example the stats package R gives a p- value of 0.02275 or 2.275% - accurate to just 4 digits - that's good enough for practical purposes. Both Excel and Calc have more digits. The point is that Calc ZTEST is *broken* and has probably always been - there is a clear and simple bug that I've found (and even provided a couple of lines of code to solve). Where Excel calculates 2.275%, Calc calculates 0.00039%. The idea of this statistic is to compare it against a preset significance level of maybe 5%, or 1% or 0.1%. Calc is giving the wrong answer; in a situation that demands a simple pass/fail answer Calc gives the wrong one. That's serious and needs action - it can't wait until someone figures out how to improve NORMSDIST's accuracy from 7 places to 13 or whatever. The good news is that it's very easy to fix :) All the best David --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
