Including an Interaction Term Between Two Independent Variables $X _ { 1 } \text { and } X _ { 2 } \text {, }$

question 35

Multiple Choice

Including an interaction term between two independent variables, $X _ { 1 } \text { and } X _ { 2 } \text {, }$ allows for the following, except that:

• A) the interaction term lets the effect on Y of a change in \(X _ { 1 }\) depend on the value of \(X _ { 2 }\)
• B) the interaction term coefficient is the effect of a unit increase in \(X _ { 1 }\) and \(X _ { 2 }\) above and beyond the sum of the individual effects of a unit increase in the two variables alone.
• C) the interaction term coefficient is the effect of a unit increase in \(\sqrt { \left( X _ { 1 } \times X _ { 2 } \right) }\)
• D) the interaction term lets the effect on Y of a change in \(X _ { 2 }\) depend on the value of \(X _ { 1 }\)

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Definitions:

Biological Diversity

The variety and variability of life forms within a given ecosystem, biome, or for the entire Earth, involving species diversity, ecosystem diversity, and genetic diversity.

Genotype

The genetic makeup of an organism, consisting of both visible and unseen traits, determined by its DNA.

Phenotype

The observable characteristic of an organism that may or may not reflect a particular genotype due to the variable expression of dominant and recessive alleles.

Law Of Independent Assortment

The Mendelian principle that genes controlling different traits are inherited independently of one another.