I used service area analysis two times (First analysis with natural break: 5000, the second analysis with natural break: 5000, 10000, 50000, 100000). However, the results of analyses on the map were pretty weird. I am not sure that It was correct. I have 3 questions relating to this (I attached two pictures about each analysis):
1) When I put 5000 meters into natural break, why It did not normally work? and why the results of the analysis show unpredictably (Please see the picture below)?
2) When compared to specific locations (location 15, location 166 and location 144) in both analyses. One serious thing was that each location 15s were shown in different on the map. Why some location showed in different from the first analysis?
3) I downloaded road data on the US Census website, and I made centroid of census tract using the "conversion" tool in ArcGIS.
How should I solve these issues, and can work normally?
First analysis [Impedance: Length (meter), natural break: 5000]
Second analysis [Impedance: Length (meter), natural break: 5000, 10000, 50000, 100000]