Timeline for How to deal with Z-score greater than 3?
Current License: CC BY-SA 3.0
11 events
| when toggle format | what | by | license | comment | |
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| Mar 16, 2017 at 16:02 | history | edited | CommunityBot |
replaced http://meta.stats.stackexchange.com/ with https://stats.meta.stackexchange.com/
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| May 17, 2014 at 8:31 | comment | added | Nick Stauner | He forgot the negative (-) sign in his comment. His answer is correct, I think. BTW, how is this question not closed yet...? | |
| May 17, 2014 at 8:30 | comment | added | Glen_b | You realize one of those two is wrong, right? | |
| May 17, 2014 at 8:25 | comment | added | Sergio | @Glen_b you are right. I fixed one of them in may answer, by writing... $P(Z<3)\approx 0$ and $P(Z<3)\approx 1$! Fixed. Thanks! | |
| May 17, 2014 at 2:19 | comment | added | Glen_b | @Sergio your inequalities contain typographical errors (they both go the wrong way). No doubt you intended them the other way around, but I think I have to mention it so that later readers are aware that $P(Z<3)\approx 1$ and $P(Z>3)\approx 0$ was what you meant. | |
| May 14, 2014 at 21:24 | history | edited | Nick Stauner | CC BY-SA 3.0 |
added 762 characters in body
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| May 14, 2014 at 21:10 | comment | added | Mr.Cat | @Sergio yes i've been told something like this related to approximation ! | |
| May 14, 2014 at 21:02 | comment | added | Sergio | @Mr.Cat, you have to transfer from $X$ to $Z$ in order to use a z-score table. Since a z-score table contains a small finite subset of values, you often must settle for an approximation. So you could also settle for $P(Z<3)\approx 0$ and $P(Z>3)\approx 1$. | |
| May 14, 2014 at 21:02 | comment | added | Nick Stauner | Basically, yes, that's the way to z-score. FWIW, using a sample mean and standard deviation in place of the population parameters yields t-scores instead. I'm not sure I understood what you were after, but there is nothing particularly difficult about handling z scores larger than 3, except maybe not being able to look up corresponding p values in a textbook table. IMO, it's better to leave the table behind and start calculating statistics anyway. | |
| May 14, 2014 at 20:54 | comment | added | Mr.Cat | i think i'v been learning things the wrong way ! i didn't got your answer, but in class they use this formula to transfer from X to Z Z = (X-μ)/σ ---> (X-MEAN)/STD am i right ? | |
| May 14, 2014 at 20:49 | history | answered | Nick Stauner | CC BY-SA 3.0 |