Are there areas in Amsterdam to avoid because of potential criminal activity....pickpockets, stealing purses, etc ?
Other than the crowds in the red light district, I found most of the central city to be relative safe - feeling. You always should be cautious where ever you are.
Put your excess cash/cards/passport in a money belt or the hotel room safe and you have defeated the problem.
No more (and or less) than anyplace else you might go.
Use your money belt (and your head) and you'll be fine wherever you wander. If you fail to use those two important devices, woe to you anywhere.
The areas to avoid in Amsterdam are the same for any European tourist destination. Train stations are notorious for petty theft as are anywhere crowds are gathered for major attractions. Read up on Rick's thoughts on the subject HERE
And what you don't carry, can't be stolen. Leave everything at the hotel what you don't need for the day.
Some will warn you off from the Red Light District, it was at one time a bit dicey at night, mainly nuisance type stuff from people trying to get you into a bar or show, guys selling drugs, people looking for handouts, etc.; but anymore, that is for the most part gone. The area is pretty tame during the day, and the architecture and canals are some of the best in Amsterdam. At night it is also nice, the only nuisance might be the random pack of guys on a party package, but that is more a concern later at night than early evening.
The best chances of having your money stolen is when there are " staged " accidents , arguments , shows . People tend to look at this and forget to look around them . Also , beware of someone asking for directions to something that's really close . You'll have a tendency to just point while their partner in crime - usually an innocent looking old lady - stands in your " blind spot " , ready to put her hands in your pockets .
Couldn't have been a serious question considering it's been one month since the OP started this thread and has yet to return. Just one post in total.