Why is an operational definition necessary when reporting research findings?

Which of the following questions is best investigated by means of a survey?

A testable prediction that drives research is known as a(n)

Researchers are interested in finding out if voters are more likely to vote for candidates who have more pleasant facial expressions. The researchers contact every hundredth person on the voter list to ask about candidate facial expressions. Which method are the researchers using in choosing the people they will call?

An individual with an exceptional memory is identified. For any given date, she is capable of recalling major events, the weather, and what she did that day. Which research method is being used if a psychologist conducts an in-depth investigation of this individual using questionnaires, brain scans, and memory tests?

Dr. Tazurphase asked 100 people who were in line to ride the largest roller coaster in the world if they would be willing to purchase and drive a flying car. He also gave each person a survey asking questions about their personalities. Based on his results, he claimed that people who are efficient and open to new things were the most willing to purchase and drive a flying car. Which of the following describes one issue with Dr. Tazurphase’s study?

Town City is considering installing new street lamps. Which question might Town City officials ask to ensure that they do not bias respondents?

Dr. Buzz wanted to understand the impact of stressful life events on irritability. He asked college students to reflect on three major stressors in their lives, and then he asked the students how many times in a week they yelled at other people. Which of the following captures how Dr. Buzz operationally defined irritability?