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Consider doing an experiment to determine the effectiveness of various insecticides in controlling pests and their impact on tomato plant productivity.

The random assignment method assigns subjects to treatments based on chance. Before the treatments are applied, random assignment establishes treatment groups that are comparable (except for chance variance). In experiments, randomization and comparison combined prevent bias or systematic favoritism.

Consider doing an experiment to determine the effectiveness of various insecticides in controlling pests and their impact on tomato plant productivity. What is the most compelling justification for assigning treatment levels (spraying or not spraying) to experimental units (farms) at random? (a)Using a random assignment, researchers can draw broad generalizations regarding insecticide effectiveness across all farms. (b) Random assignment will tend to average out all other uncontrolled parameters like soil fertility, ensuring that treatment effects are not confounded. (c) The impacts of other variables, such as soil fertility, are eliminated by random assignment. (d) Random assignment eliminates response variability due to chance. (e) The placebo effect is mitigated by random assignment.

You can assign those individuals to either of the two assignments at random. By allocating treatments at random, we hope to make the different groups look as comparable as possible, reducing the chance of a confounding variable. As a result, option (b) is correct.