From the independent variables used in the outcome equation,
product prices and the income of the house were used
logarithmically. The number of individuals in the family was used as
independent variables. The models also included a dummy variable
that represented whether the product in question was frozen or not
and which would enable the calculation of a price threshold at
which the consumers would be willing to pay for the frozen
products. When the coefficient of this dummy variable was
significant, willingness to pay was calculated.