How to find tops and bottoms in time series?

Question

At first, this question can sound really stupid, but it is not in fundamental. Maybe, it can seem like unresolvable exactly by any algorithm, but I pretend to say it is.

Answer 1

You'll usually start with a moving average -- that is, averaging the N most recent points, where the degree of smoothing is roughly proportional to N (i.e., as yoy average more points, your result gets smoother).

Then you can take the differences between each averaged point and the next. Where the difference changes sign, you have a minimum or maximum (where it goes from positive to negative, you have a maximum, from negative to positive, a minimum).