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You are not logged in. #1 20130911 13:43:48
average number of years since new record.I was thinking of a math problem that I've never seen before. My reasoning is as follows... The probability of the first year record still standing after 5 years is because each of the following 4 years has 50% chance of breaking it or not. The probability of the second year setting a new record is and the probability of it still standing after the following 3 years is And so on... Is this correct or not? The eclipses from Algol (an eclipsing binary star) come further apart in time when the Earth is moving away from Algol and closer together in time when the Earth is moving towards Algol, thereby proving that the speed of light is variable and that Einstein's Special Theory of Relativity is wrong. #2 20130911 16:46:17
Re: average number of years since new record.Hi Fruityloop;
I would question that. Each record would be harder and harder to break. Also, setting the first probability to 50 % is arbitrary. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20130912 12:58:57
Re: average number of years since new record.Thank you for your response Bobbym.
I'm comparing the following 4 years only to the first year. Last edited by Fruityloop (20130912 12:59:37) The eclipses from Algol (an eclipsing binary star) come further apart in time when the Earth is moving away from Algol and closer together in time when the Earth is moving towards Algol, thereby proving that the speed of light is variable and that Einstein's Special Theory of Relativity is wrong. #4 20130912 22:03:46
Re: average number of years since new record.Hi Fruityloop; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #5 20130919 07:33:28
Re: average number of years since new record.I feel like such a dingdong. I think I know the answer now. I generated 65 random numbers between 1 and 1300 inclusive and did this 50 times. The average number of numbers since the alltime high number was 30.28 which is close to 33 which is what we would expect. Let's say you have temperature records going back 130 years, the average number of years since the alltime high record would be 65.5. To me this seems counterintuitive because it seems like later years would be more likely to hold the alltime high records. Last edited by Fruityloop (20130919 07:44:22) The eclipses from Algol (an eclipsing binary star) come further apart in time when the Earth is moving away from Algol and closer together in time when the Earth is moving towards Algol, thereby proving that the speed of light is variable and that Einstein's Special Theory of Relativity is wrong. #6 20130919 07:53:08
Re: average number of years since new record.How is that probability 1/N? It seems rather arbitrary. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #7 20130919 11:53:28
Re: average number of years since new record.Each year has an equal probability of being the recordholder. There are N years. So for each year the probability of it being the recordholder is 1/N. Let's say you have N balls in a bag, they are numbered 1 to N. You reach into the bag and pull out a ball at random and without looking at the number on the ball, you write a random number between 1 and 1500 on the opposite side of the ball. You do this for all of the N balls. Which numbered ball will have the highest number? It is easy to see that each ball has an equal chance of having the highest number. The eclipses from Algol (an eclipsing binary star) come further apart in time when the Earth is moving away from Algol and closer together in time when the Earth is moving towards Algol, thereby proving that the speed of light is variable and that Einstein's Special Theory of Relativity is wrong. #8 20130919 18:21:05
Re: average number of years since new record.What if none of them is a record holder? And, besides, it's something you can only guess to have a probability you think it has. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #9 20130919 19:53:34
Re: average number of years since new record.
I don't agree with that assumption. With climate changes, for example, if, say, it is getting wetter, then the probability of a new record gets higher as each year passes, and diminishes if it is getting dryer. You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #10 20130920 14:18:43
Re: average number of years since new record.Thanks for the responses. I was assuming an unchanging climate in my problem. The eclipses from Algol (an eclipsing binary star) come further apart in time when the Earth is moving away from Algol and closer together in time when the Earth is moving towards Algol, thereby proving that the speed of light is variable and that Einstein's Special Theory of Relativity is wrong. 