Been an adsense publisher for quite a few years now. In the early days i was paranoid about getting banned although I wasn't doing anything that i knew to be wrong. Anyway my more recent complacency has been jarred by the deduction for october earnings for invalid clicks. Previous months it was <1% of earnings. Last month it jumped to around 8%.
I don't do any of the things you would worry about: dont click my own ads, none of my family or friends even know what my sites are, traffic is all organic. A few of my sites do generate a high ctr (up to 9%) and a highish cpc (they are in a niche that advertisers are throwing money at at the moment) although my overall account ctr is nearer 2%.
So - at what rate of invalid click deductions do i need to worry that my account may get closed?