The anchoring bias and how it affects our decision

The anchoring bias is a cognitive bias whereby the first information we get affects our subsequent actions and decisions.
That first information functions as an “anchor” to our future perception, judgments and decisions.
The accuracy and the relevance of the anchor is not important. Once an anchor is set, we tend to adapt our thinking and behaviour to agree with it. 

A simple example would be a person who after buying a fancy coat at a rather steep price, a lavish meal at a Michelin restaurant becomes accessible.
The high price of the coat acted as an anchor and warped his perception of value, to the point where the price of a fancy dinner seemed affordable in comparison.
The anchoring bias can cause us to make erroneous decision based on "anchor" data, if we fail to adjust our perception to realistically assess new information.
To mitigate the effects of this bias, we need to question and challenge our initial impressions by comparing them with multiple sources, and consciously re-evaluating decisions from a new perspective rather than relying on "anchor" or first impressions.