Timeline for Can anyone clarify the concept of a "sum of random variables"
Current License: CC BY-SA 3.0
22 events
| when toggle format | what | by | license | comment | |
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| Feb 4 at 14:38 | comment | added | kjetil b halvorsen♦ | Have a look at What is meant by a "random variable"? | |
| Sep 1, 2022 at 12:15 | history | protected | kjetil b halvorsen♦ | ||
| Oct 5, 2018 at 22:38 | answer | added | Daniel Li | timeline score: 8 | |
| S May 11, 2014 at 2:16 | history | bounty ended | Glen_b | ||
| S May 11, 2014 at 2:16 | history | notice removed | Glen_b | ||
| S May 6, 2014 at 22:30 | history | bounty started | Glen_b | ||
| S May 6, 2014 at 22:30 | history | notice added | Glen_b | Reward existing answer | |
| May 2, 2014 at 12:00 | comment | added | bdeonovic | Great answers have been given. Another good example is the sum of two dice, $X+Y$. The result is clearly random (you don't know in advance what the sum of both of the die will be). We know that $X,Y\sim Unif(1,6)$ and independent. It turns out that $X+Y$ has a triangular distribution. | |
| May 2, 2014 at 11:35 | answer | added | jolvi | timeline score: 4 | |
| May 2, 2014 at 2:41 | vote | accept | Gosset | ||
| May 2, 2014 at 2:41 | vote | accept | Gosset | ||
| May 2, 2014 at 2:41 | |||||
| May 1, 2014 at 20:55 | history | tweeted | twitter.com/#!/StackStats/status/461972168042352640 | ||
| May 1, 2014 at 20:10 | vote | accept | Gosset | ||
| May 2, 2014 at 2:41 | |||||
| May 1, 2014 at 20:03 | answer | added | Aksakal | timeline score: 4 | |
| May 1, 2014 at 19:58 | answer | added | whuber♦ | timeline score: 58 | |
| May 1, 2014 at 19:56 | comment | added | Gosset | @Aksakal Isn't the fact that I posted this question evidence of that already? Perhaps if you do know it, you could clarify the concept? | |
| May 1, 2014 at 19:49 | comment | added | Aksakal | I think your problem is that you don't understand what is a random variable. If you get this concept then the sum will come easily too. | |
| May 1, 2014 at 19:47 | comment | added | Gosset | @PeterR This is what I don't understand. How does it even make sense to talk about adding something that doesn't have a value yet? Is it a metaphorical type of summing? | |
| May 1, 2014 at 19:39 | history | edited | gung - Reinstate Monica | CC BY-SA 3.0 |
added tag; removed peripheral comments; light editign
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| May 1, 2014 at 19:36 | review | First posts | |||
| May 1, 2014 at 19:39 | |||||
| May 1, 2014 at 19:33 | comment | added | PeterR | By 'realizations of a random variable' I assume you mean the actual observed values. What is being summed in the 'sum of random variables' is the random variables before they are observed. Imagine calculating the weight of the next 5 people to get on the elevator. You dont know their weights (yet) and so they are each a random variable. But you probably would like to know something about the distribution of the sum of their weights. | |
| May 1, 2014 at 19:18 | history | asked | Gosset | CC BY-SA 3.0 |