When doing nanoparticle tracking analysis, one of the end goals is to produce a histogram of sizes. However, the number of frames over which particles are tracked limits the accuracy of the method. Therefore, we could assign more statistical relevance to the particles that are tracked for longer[@walker2012Improved nano-particle tracking analysis].

Also, see the approach on nanoparticle tracking in hollow optical fibers, in which they[@fo2020Tracking and Analyzing the Brownian Motion of Nano-objects Inside Hollow Core Fibers] simply multiply each particle's information by the number of frames over which it was observed.