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Chapter 1: Q 1.5. (page 7)

Define the following terms:

(a) Observational study

(b) Designed experiment

Short Answer

Expert verified

Part (a) Researchers observe attributes and take measurements in an observational study with no attempt to influence anything.

Part (b) Researchers impose treatments and controls in a planned experiment, then observe and measure features.

Step by step solution

01

Part (a) Step 1. Given information.

The given term is "Observational study".

We have to define the given term "Observational study ".

02

Part (a) Step 2. Define Observational study.

In an observational study, individuals are examined in a sample to determine the characteristics of a population, but it does not endeavor to modify or influence the variable of interest.

03

Part (b) Step 1. Given information.

The given term is "Designed experiment ".

We have to define the given term "Designed experiment ".

04

Part (b) Step 2. Define Designed experiment.

A designed experiment is one in which a treatment is applied to individuals or experimental units with the purpose of isolating the treatment's influence on a response variable.

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