Even though variables, interactions, and influences in the model sound like they are created
just for an individual, they are formed considering the average of all middle-income people in
Turkey. In the model, individuals are assumed to pay their necessary spending by cash, and
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then all excessive spending is paid by credit card. Subsistence spending of people with middle
income includes housing, eating, transportation spending. However, it should not be confused
with minimum wage. Lastly, although credit card payments occur discretely in real life, from
our macro perspective, which is necessary to build such a model, payments are assumed to be
continuous.