Eli, you write “In the sense of models, there is no data that is perfectly correct although some is useful. The trick is to understand the limitations of the measurement.”
I have absolutely no idea what you are talking about. The only limitation to actual measurements that I am aware of, is the error inherent in making any measurement. Why there is a trick to understand error bars, I have no idea. And what models have to do with measurement, I have equally no idea whatsoever.