Is there any difference between inter-arrival time and interval time?


I am wondering some statistical books write inter-arrival time and other write interval time.
Is there any difference between them? if so, how can I calculate both?
Who is Participating?
TommySzalapskiConnect With a Mentor Commented:
Inter-arrival time is usually used to refer to the time between events.
Interval time is usually used to refer to the length of time you observe for events.

For example, if you are looking at calls to a datacenter and there are 10 calls per minute your inter-arrival time would be 6 minutes.

And if you looked at 1 hour intervals, the number of calls per interval would be 600.

I hope that helps.
TommySzalapskiConnect With a Mentor Commented:
So generally you pick the interval, and then inter-arrival time is just interval/count_of_events
amq10Author Commented:
Hi Tommy,

is the inerval like arrival rate ?
A proven path to a career in data science

At Springboard, we know how to get you a job in data science. With Springboard’s Data Science Career Track, you’ll master data science  with a curriculum built by industry experts. You’ll work on real projects, and get 1-on-1 mentorship from a data scientist.

TommySzalapskiConnect With a Mentor Commented:
Interval is just a time period.
If you sample at 1 hour intervals, then that's your interval. 1 hour.

If that's not what you are talking about, perhaps you could point us to something that would help us understand how it is being defined in your case.
amq10Author Commented:

I have arrival time like the below:

for more than 3000 requests. I need to get lambda to calculate the Poisson distribution. can you help me how can get that ?
lambda is just the average time between events. So divide the number of events by the total time.

If you have a start and end time, use total_requests/(end_time - start_time)

If you just have the times, then use (total_requests-1)/(last_request_time - first_request_time)
You subtract 1 because you have no way of knowing (in this case) how long it took for the first event to happen.
amq10Author Commented:
Thanks you. it is so clear
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.