Descriptive research is used for all the reasons below except $\_\_\_\_\_\_\_.$

$1$ to understand which variables are the cause and which variables are the effect of a phenomenon

$2$ to describe the characteristics of relevant groups, such as consumers, salespeople, organizations, or market areas

$3$ to determine the degree to which marketing variables are associated

$4$ to determine the perceptions of product characteristics

$5$ Descriptive research is used for all of the reasons listed.