The Owners of an Online Shop Use a Multiple Regression

question 19

Multiple Choice

The owners of an online shop use a multiple regression model with three independent variables where ​ y = Shipping Cost ($) ​ x₁ = Product weight (kg) ​ x₂ = Number of items ​ x₃ = Total amount ($) ​ The regression model is ​ y = 8.50 + 12x₁ + 0.1x₂ + 0.05x₃ + 0.08x₂x₃ + e ​ Interpret the value of β₁ for this model. ​

• A) The average change in shipping costs associated with an increase in the number of items by 1 when the product weight and the total amount are held fixed.
• B) The average change in shipping costs associated with a 1-dollar increase in the total amount when the product weight and the number of items are held fixed.
• C) The difference between the slopes of regression lines depending on the total amount and the number of items.
• D) The average change in shipping costs associated with a 1-kg increase in product weight when the number of items and the total amount are held fixed.
• E) The average change in shipping costs when the perceived increase value of the number of items by 1 unit depends on the change of the total amount.

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Definitions:

Zone of Proximal Development

A concept in developmental psychology referring to the difference between what a learner can do without help and what they can achieve with guidance and encouragement from a skilled partner.

Guided Participation

Adult’s participation in a child’s activity that helps to structure it and bring the child’s understanding of it closer to the adult’s.

Lev Vygotsky

A Russian psychologist known for his theory on social interaction playing a fundamental role in cognitive development.

Prelinguistic Speech

The stage in infant development characterized by making sounds and babbling, before the emergence of recognizable words and language.