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Quant版 - 等bus的问题
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话题: memoryless话题: uniform话题: time话题: buses话题: bus
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1 (共1页)
h**********y
发帖数: 41
1
You are waiting for a bus at station. If the buses have an average arrival
time of 10 minutes and you arrive at the bus station at a random time. What
is your expected waiting time if the buses arrive according to a uniform
distribution? If you have waited for 2 minutes, how many more minutes do you
expect to wait?
绿书里给出了Poisson process的解法,但我想知道这类题目更一般的解法,如果换成
是uniform distribution 或其他将怎么解呢?
k*****y
发帖数: 744
2
请问如何定义buses arrival according to a uniform distribution?
Poisson process是从N(t) = # of arrivals at t开始定义,然后可以推出based on任
意时刻a,下一辆车到达的时间差是exponetial分布,跟时刻a无关,相当于memoryless
。所以expected waiting time可以make sense。
反过来定义的话,如果要得到memoryless的uniform似乎不是well defined的。

What
you

【在 h**********y 的大作中提到】
: You are waiting for a bus at station. If the buses have an average arrival
: time of 10 minutes and you arrive at the bus station at a random time. What
: is your expected waiting time if the buses arrive according to a uniform
: distribution? If you have waited for 2 minutes, how many more minutes do you
: expect to wait?
: 绿书里给出了Poisson process的解法,但我想知道这类题目更一般的解法,如果换成
: 是uniform distribution 或其他将怎么解呢?

i**w
发帖数: 71
3
绿皮书上有提到,residual time和对应的reference.我还被问到过一次。

【在 h**********y 的大作中提到】
: You are waiting for a bus at station. If the buses have an average arrival
: time of 10 minutes and you arrive at the bus station at a random time. What
: is your expected waiting time if the buses arrive according to a uniform
: distribution? If you have waited for 2 minutes, how many more minutes do you
: expect to wait?
: 绿书里给出了Poisson process的解法,但我想知道这类题目更一般的解法,如果换成
: 是uniform distribution 或其他将怎么解呢?

c********d
发帖数: 173
4

memoryless

【在 k*****y 的大作中提到】
: 请问如何定义buses arrival according to a uniform distribution?
: Poisson process是从N(t) = # of arrivals at t开始定义,然后可以推出based on任
: 意时刻a,下一辆车到达的时间差是exponetial分布,跟时刻a无关,相当于memoryless
: 。所以expected waiting time可以make sense。
: 反过来定义的话,如果要得到memoryless的uniform似乎不是well defined的。
:
: What
: you

c********d
发帖数: 173
5
他意思是interarrival time是uniformly distributed
定义没有问题的。

memoryless

【在 k*****y 的大作中提到】
: 请问如何定义buses arrival according to a uniform distribution?
: Poisson process是从N(t) = # of arrivals at t开始定义,然后可以推出based on任
: 意时刻a,下一辆车到达的时间差是exponetial分布,跟时刻a无关,相当于memoryless
: 。所以expected waiting time可以make sense。
: 反过来定义的话,如果要得到memoryless的uniform似乎不是well defined的。
:
: What
: you

R**T
发帖数: 784
6
我这认为这个题对于非memoryless的分布并不是well-defined
具体来说我觉得"the guest arrives at the train station randomly"这个randomly
不好定义

memoryless

【在 k*****y 的大作中提到】
: 请问如何定义buses arrival according to a uniform distribution?
: Poisson process是从N(t) = # of arrivals at t开始定义,然后可以推出based on任
: 意时刻a,下一辆车到达的时间差是exponetial分布,跟时刻a无关,相当于memoryless
: 。所以expected waiting time可以make sense。
: 反过来定义的话,如果要得到memoryless的uniform似乎不是well defined的。
:
: What
: you

1 (共1页)
进入Quant版参与讨论
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话题: memoryless话题: uniform话题: time话题: buses话题: bus