Errors in Scientific Research and the Importance of Accurate Results

1. Psychology IFri, 3/2 Did you know?? Scientific research does not always produce error-free results. Often, errors are the result of mistakes in applying the scientific method. Scientists may hope for a particular outcome; it is important not to let this affect the results or their interpretations. Another mistake is to ignore data that do not support the hypothesis. It is important to handle all data in the same way. Yet another mistake arises from the failure to account for errors. Some discoveries have been missed by experimenters who did not recognize a new phenomenon when they were faced with it, as well as “new discoveries” (such as those made in the Hawthorne study) that turned out to be invalid. For this reason, active experimentation (including replication) and open communication among members of the scientific community are essential in providing accurate results. Please get out your textbook, Ch 2, Sec 2 Outline, & Ch 1 Summative Assessment

2. Agenda • Ch 1 Summative Assessment Discussion Time • Chapter 2, Section 2-start • To Prepare for Class on March 5/6: • Read Chapter 2, Section 3 • Take notes using a graphic organizer of your choosing. • Write a couple sentences explaining why you chose the graphic organizer that you did.

3. Chapter 2: Psychological Methods • The Big Idea: • Psychologists use a variety of methods to conduct research. • Essential Question: • What are surveys, and how can psychologists use them to find out about people’s attitudes and behaviors? • Objective: • In a survey’s findings identify various the purpose, the sample, and how the survey was conducted.

4. What are surveys, and how can psychologists use them to find out about people’s attitudes and behaviors? • Surveys, Samples, and Populations • Scientists use the survey method by interviewing people or by distributing questionnaires. • Scientists must carefully choose which groups of people they wish to study. • One way to gather information is by asking people directly. Psychologists use this method to study people’s attitudes and behaviors.

5. The Survey Method • How is survey data analyzed? • What are some of the limitations of surveys?

6. Populations and Samples • Why is identifying the target population key to a survey? • How might studying the wrong group affect the outcome of a study?

7. Stratified Samples • Look at the chart on page 41. • In a stratified sample consisting of 100 people, how many African Americans would you expect to find in the sample? • In a stratified sample of 100 Americans, how many White non-Hispanics would you expect? • How would you obtain an accurately stratified sample for a study having to do with life in American cities?

8. Selecting Samples • How are samples selected? • Why might it be preferable to use a stratified sample rather than a random sample?

9. Generalizing Results • What does it mean to generalize results? • What is an example of a study in which researchers would only want to find out about one group within the general population?

10. Volunteer Bias • What might a psychologist say about a person who has a disposition to a certain point of view? • Why might there always be a bias in survey results? • What is volunteer bias? • How do volunteers’ outlooks differ from those of people who do not volunteer?