1. IP address.

if someone or you click the ads that come from the same IP address you use to access your AdSense account, your account is flagged.

2. Click Through Rate/Click Through Rate (CTR).

Typically, the Click Rate should not exceed 10%. If not, Google will mark your account. For your information, the normal CTR should range between 0.5% – 10%.



3. The location.

Google has a tracking software and technology. They can trace the origin of the traffic to the small town. So, using different computers with different IP addresses does not secure anything. So, don't try to click on your ad from different internet cafe or public. It will kill you.

4. Cookies.

Most home users do not use a static IP address for your internet connection. In most cases just disconnect and reconnect the internet will give you a new IP Address. But remember, Google has set a cookie on your computer. They can track the cookie sand see if they come from the same computer
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5. The pattern of Illegal Clicks 1.

It is also suspicious, when there are visitors who click the ads there, after click they leave your website (hit and run). Normal visitors normally browse through website's content beforehand, after they see there are ads that get them interested recently there is a possibility that a click is a click.

Continue reading here

http://citybaze.com/2016/12/06/11-ways-google-adsense-detect-invalid-clicks/

I don't understand why some people cannot just make money legitimately. They choose to break rules to make quick money. Thunder does not need t fire them because Google is doing their job very well using the variables you highlighted. That's why you see them everywhere shouting "Google has banned my account, what should i do?". Kill Yourself.

This is to know that you cannot cheat on google. FP tins