Timeline for Calculate variance from mean and variance of bins [duplicate]
Current License: CC BY-SA 3.0
11 events
| when toggle format | what | by | license | comment | |
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| Jul 9, 2016 at 12:06 | comment | added | Glen_b | It's one of those things everyone calls a different name. It's a hard thing to search for. | |
| Jul 9, 2016 at 11:29 | vote | accept | Managarm | ||
| Jul 9, 2016 at 11:29 | comment | added | Managarm | Ahh, "partitions" didn't occur to me. Thanks! | |
| Jul 9, 2016 at 11:22 | comment | added | Glen_b | A formula is given at the linked duplicate (see the "unequal sample size formula"), since this is just a special case of calculating overall means and variance from grouped data. A derivation for it is here. | |
| Jul 9, 2016 at 11:20 | history | closed | Glen_b | Duplicate of How to calculate the variance of a partition of variables | |
| Jul 9, 2016 at 11:06 | answer | added | mdewey | timeline score: 1 | |
| Jul 9, 2016 at 11:00 | history | edited | Managarm | CC BY-SA 3.0 |
Added more details
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| Jul 9, 2016 at 10:42 | comment | added | Glen_b | ctd... 3. You say you only have the means and variances in each bin. Is this actually true, or do you also have the count of how many values fell into each bin? | |
| Jul 9, 2016 at 10:37 | comment | added | Glen_b | 1. When you say "gets values from 900 to 999" this implies that the values are integer (because otherwise values between 999 and 1000 would not go into either bin 9 nor into bin 10). If the values are integer they are not normally distributed and if they are not integer you have incorrectly (/misleadingly) described what happens to the values. Please fix your description so that it is consistent with the actual situation. $\:$ 2. Many algorithms are named after Knuth. What algorithm is this? ... ctd | |
| Jul 9, 2016 at 10:25 | review | First posts | |||
| Jul 9, 2016 at 10:56 | |||||
| Jul 9, 2016 at 10:24 | history | asked | Managarm | CC BY-SA 3.0 |