A Team of Researchers Is Investigating the Effects of Fertilizer

question 56

Essay

A team of researchers is investigating the effects of fertilizer on the growth of forest trees. They use an old Christmas tree plantation with pine trees of the same species and age, and divide a section of the plantation into 60 plots. They separate the plots into two groups of 30. They apply high fertilizer levels to the group to the east of the plantation and low fertilizer levels to the western group. They set up the experiment to run for ten years and measure growth of all trees at the end of each year. Discuss the validity of the experimental design, concentrating on the formation of treatment groups and the use of controls. Based on this design, would the researchers be able to draw valid conclusions about the effect of fertilizer on tree growth rates? Why or why not?

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Definitions:

Straight-Line Demand

Straight-Line Demand refers to a demand curve that shows a constant rate of change in the quantity demanded as price changes.

Percentage of Income

A measure indicating what portion or ratio of one's income is allocated to a specific expenditure or category.

Unit Elastic

Describes a situation in which the percentage change in quantity demanded is equal to the percentage change in price, leading to no change in total revenue.

Income Elasticity

A measure of how much the demand for a good will change in response to a change in consumer's income.