We managed to gather data for about a month when building this app. Some of them were as recent as a few hours and some a few days. We implemented a weighted a

We managed to gather data for about a month when building this app. Some of them were as recent as a few hours and some a few days. We implemented a weighted average algorithm to calculate the risk levels and how confident we were of the data. For the risk levels I took into account 1) How recent the data was 2) What time of the day it occurred relative to the time of query (for eg: the crime occurred at 4pm on another day and its 5pm now, it will be given a higher weightage compared to something that happened at say, 11am.) 3) The severity of the crime itself (murders >> theft) 4) Number of occurrences of crimes in the area The assignment of weights wasn't thoroughly scientific though. It needs some tweaking. And thanks for the suggestion on push notifications :)