To determine the amount of time that a person will decide to devote to watching online videos each week, an economist makes the assumption that the individual will feel overwhelmed by the sheer volume of videos available online and will
respond by using a rule of thumb.
in examining the above decision-making process, the approach that the economist is following can best be described as the one that relies on

the assumption of bounded rationality

Explanation:

What is a bounded rationality?

A bounded rationality means we use our prototype to relate to the situation that we are trying to resolve due to the lack of information and time available to us.

This is a rule of thumb or a view of heuristic in which we can use our preexisting information in order to make a decision or make judgements.

For example if we see someone reading horoscopes frequently and they believe in visions at all times if someone were to ask us if that someone is a teacher or a spiritual healer we are likely to say that she or he is a spiritual healer due to the information that already exist in our mind.

Using a rule of thumb may result to accurate judgements and sometimes inaccurate judgements or decisions.