River City Is Seeking to Compare the Effects of Two

question 36

Essay

River City is seeking to compare the effects of two mosquito sprays, A and B, to beused in the insect control plan for their park system. Consider the following twoplans for a statistical study:• In Plan #1, a simple random sample of plots of park land would be taken from thepopulation of River City parks. Either treatments A or B would be randomlyassigned to each of the plots.• In Plan #2, simple random samples of plots of park land would be taken fromeach of four geographic areas in River City. (River City has 4 geographic areas oftown, the NE, NW, SE, and SW quadrants.) Either treatments A or B would berandomly assigned to each of the plots within each geographic area.
a) Consider study plan #1:i) Would it be appropriate to infer a cause-and-effect relationship if the results ofthe two treatments differ?
Why or why not?
ii) Could the results be generalized to all areas of the park land?
Why or whynot?
b) Consider study plan #2:i) Would it be appropriate to infer a cause-and-effect relationship if the results ofthe two treatments differ?
Why or why not?
ii) Could the results be generalized to all areas of the park land?
Why or whynot?

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Definitions:

Embryonic Cells

Cells derived from an embryo that have the potential to develop into any type of cell in the organism.

Crossing-Over

A process during meiosis where homologous chromosomes exchange genetic material, leading to new genetic combinations in offspring.

Genes

Units of heredity made up of DNA that code for the synthesis of proteins responsible for the organism's characteristics and functions.

Chromosome

A long DNA molecule with part or all of the genetic material of an organism.