Don’t forget there was scuba diving as well. There were small airports around(if Z was a Flyer), lots of activity. Heck, maybe Z was a wine fan, and was checking out vineyards

The days upon which he posted his letters is also interesting….( counting the first three as one up until march 13 1971,,,We have 13)
Thursday, Weekend ( 2nd letter received on Monday 4th), Monday, Saturday, Sunday, Saturday, Monday, Tuesday, Friday, Friday, Sunday, Tuesday, Saturday.

With a couple of exceptions many were posted on weekends and/or beginning or end of the week. Again we can’t be sure but it appears ( all things being equal) that not only did he work during the week but held some job that kept him pretty occupied. While perfectly possible, I don’t think it necessarily means Zodiac worked or lived in San Francisco because the letters we posted from there. Maybe he was some kind of driver or something like that who’s job took him to S.F or perhaps he just decided to post from there.

Here’s a recent study that used an interesting mathematical technique to discover the identity of street artist Banksy:

https://www.rt.com/news/334514-banksy-c … i-tagging/

Kim Rossmo is one of the authors of the study:

http://www.tandfonline.com/doi/full/10. … 16.1138246

Here’s the paper:

https://drive.google.com/file/d/0Bx2ZxP … sp=sharing

doranchac.. I think that Arthur lee alan would be the clear higher percentage taker in this type of profiling theory
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