How does accept rate work?
How can I increase my accept rate for asking questions? And for each question, does the question rate differ ?
When you accept an answer, your accept rate will improve. If you accept one answer for each question you have asked your accept rate will be 100%.
There is no difference on a particular site, although your accept rate may be different on different SE sites.
Your accept rate is based on if you accept answers to your questions!
If you have asked 5 questions and accepted 4, your accept rate will be 80%.
However, you should only accept answers if they do answer your question. If you think no one has answered a question, you can answer your question yourself and accept that.
You will not get additional reputation for asking accepting your own answer, but it will keep your accept rate 100%.