Sorry, I meant to add - given the number of students walking to and from the uni at night, eg: from the library that area has quite good lighting. And there are also considerations for student safety, so you could factor that into the general safeness of the area. Most people walking aorund that area would have good reason, rather than being young people out seeking trouble or to cause trouble.
Stirling Hwy in Nedlands is very busy with traffic, so I would make sure that all windows and doors were safely locked. There are lots of students living in similar circumstances, in the student housing that is especially designed for them.