I found you a link to the San Francisco Police Department's CrimeMAPS website. that's the best advice that i can offer you is to talk directly with local law enforcement, preferably the local sub-station cloest to the location in question and consult other in the community, neighbors, etc. Especially if this is a concern to you and your family. In answering this question it is not my intention to be an expert on this subject, especially in San Francisco, CA. So seek aditional advice.