The document discusses key aspects of conducting psychological research, including the importance of replication, sampling techniques, and generalizability. It notes that for findings to be confirmed, studies must be replicated to show consistent results. Proper sampling, such as random or stratified sampling, is important to ensure samples accurately represent the overall population. Researchers must be cautious when generalizing results to avoid volunteer bias from non-random samples.

1. PPSSYYCCHHOOLLOOGGYY
PRINCIPLES IN PRACTICE
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Conducting Research (general info)
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 Psychology is an experimental science
 Assumptions must be supported by evidence
 Procedures consists of five steps:
1) Forming a research question
2) Forming a hypothesis
3) Testing the hypothesis
4) Analyzing the results
5) Drawing conclusions

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PRINCIPLES IN PRACTICE
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Replication
 Findings may represent a random occurrence
 For a study to be confirmed it must be
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replicated (repeated) to show the same results
 If the results are repeated and obtain different
results, the findings of the first study are
questioned
 It is important to study both males and females
if the goal is to make generalizations about all
members of the species.

3. PPSSYYCCHHOOLLOOGGYY
PRINCIPLES IN PRACTICE
New Questions
Whether the findings of the research study
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support or contradict the hypothesis, they are
likely to lead to new research questions.
 Once new questions are asked, the process
begins all over again.

4. PPSSYYCCHHOOLLOOGGYY
PRINCIPLES IN PRACTICE
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5. PPSSYYCCHHOOLLOOGGYY
PRINCIPLES IN PRACTICE
Question: Why are proper sampling techniques important?
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Surveys are taken to find out about people’s attitudes
and behaviors directly.
Two survey methods—written questionnaires and
interviewing
The findings of interviews and questionnaires are not
completely accurate.
People may not answer honestly about their
attitudes or behavior

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PRINCIPLES IN PRACTICE
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Populations and Samples
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Must decide what group or groups of people
they wish to examine and how they will be
selected.
 Target population—is the whole group you
want to study or describe.
 Researchers study a sample of the target
population

7. PPSSYYCCHHOOLLOOGGYY
PRINCIPLES IN PRACTICE
Selecting Samples
 Samples must be selected scientifically to ensure that
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the samples accurately represent the populations they
are supposed to represent.
 Random Sample—individuals are selected by
chance from the target population
 Stratified sample—subgroups in the
population are represented proportionally in
the sample.

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PRINCIPLES IN PRACTICE
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A random sample of 1,000 to 1,500
people will usually represent the
general American population
reasonably well.
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9. PPSSYYCCHHOOLLOOGGYY
PRINCIPLES IN PRACTICE
Generalizing Results
 Researchers do not use a sample that represents an
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entire population
 Researchers want to know about only one group
within the population
 Researchers are cautious about generalizing their
findings to groups other than those from which
their samples were drawn

10. PPSSYYCCHHOOLLOOGGYY
PRINCIPLES IN PRACTICE
Volunteer Bias
 Researchers have little control over who responds to
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surveys or participates in research studies.
 They cannot force people to complete the
questionnaires.
 Bias—a predisposition to a certain point of view.
 People who volunteer to participate in studies often
bring with them a volunteer bias.