Chapter 9, Problem 9.19CYS

To determine

The type of study for the given example.

Answer to Problem 9.19CYS

Option (a): an observational study.

Explanation of Solution

Reason for the correct answer:

The study is about ‘victimization during adolescence has an impact on depression in early adulthood or not’. The researcher has examined 3,898 participants and collected information about the victimization of peers at the age 13 and depression at the age 18. It can be observed that only the peers were observed and measured and no modifications were done for individuals during the study. This implies that the study is observational.

Reason for the incorrect answers:

Option (b): The study is not the randomized comparative experiment as the subjects are not divided into groups for assigning the treatments randomly to the subjects.

Option (c): The study is not matched pairs experiment as on the same subjects, two types of treatments are not compared with each other.

Conclusion:

Thus, the study ‘victimization during adolescence has impact on depression in early adulthood or not’ is an observational study.

Statistics Concept Introduction

Introduction:

Observational study:

If the individuals under the study are just observed and measured based on certain characteristics without modifying them, then the study is termed as observational study.

Randomized comparative experiment:

In a randomized comparative experiment, similar groups of the subjects are formed. In this experiment, the subjects are randomly assigned to two or more treatments for comparison purpose.

Matched pairs experiment:

In matched pair design, two treatments are assigned randomly to the same subject that is each subject receives two types of treatments and are compared for the effect of the treatment. It is the experiment which is used for comparing two treatments using blocking factor.