Detect patterns in data set

Question

Given a data set with several records, that are similar to this one:

I want to detect the green dots. This pattern is recurring in a lot of the data records but is not completely identical (sd, variance, min, max etc). This data points are near the minimum and are showing a low variance.

I tried clustering (kmeans, dbscan, mclust) but the result was not very good. How can I solve this problem? Any ideas?

Answer 1

Dare I say a simple threshold based on the minimum and a percentage?