Chapter 1: Psychology,

Research, and You Pages 2 – 21

Food for Thought When the city’s ice cream

sales are highest, the number of drownings is also highest; therefore, increasing ice cream sales causes an increase in drownings.

A series of Dutch statistics shows that an increase in the number of storks nesting in the area during the spring was related to an increase in the number of human babies born at that time. More storks must mean more babies, right?

Definitions of Psychology The science of behavior and mental

processes “Inner” experiences like dreams Scientific testing and causal relationships

Becoming a Psychological Detective

What is the claim and who is making it? Personal Bias Evaluate authority Cultural Bias

Whose face is on a penny? Who stole the greatest number of bases in a

single season of professional baseball?

Becoming a Psychological Detective

Is the claim based on scientific observations? Does the claimant use personal experiences or

documented research?

Becoming a Psychological Detective

What do statistics reveal? Are the test results statistically significant?

Becoming a Psychological Detective

Are there plausible alternative explanations? Spurious relationships

‘A’ may be related to or correlate with ‘B’, but ‘A’ does not cause ‘B’

There is another explanation

The Incredible Edible Egg Bias? Personal gain? Observations?

My dad says…

Statistics? Most vitamins are very low in amount, less than 1%

Other explanations? Good nutrition and exercise

http://youtube.com/watch?v=UmPwL1YulMA

“Trimspa, Baby”

What are they selling? Bias? Statistics?

Results not typical

Other explanations? Plastic surgery http://youtube.com/watch?v=u9oMEfFlmYQ

Review When evaluating a claim, ask:

What is the claim and who is making it? Is the claim based on scientific observations? What do statistics reveal? Are there plausible alternative explanations for

the claim?

Research Methods in Psychology Scientific Method

Make careful and precise observations of a phenomena or event

Develop an explanation, a theory Develop a hypothesis

Prediction about future behaviors Test and retest the hypothesis

Types of Research Methods The Case Study Naturalistic Observation Correlational Research Survey Research These methods cannot give us a cause-

and-effect statement

Types of Research MethodsThe Case Study

Also called a clinical study In Depth One Person or Few People Uses data from one person to understand

the behavior in others

Types of Research Methods:The Case Study Advantages

Researchers can gather a lot of detailed information

Provides suggestions for further research

Disadvantages Not always

generalizable What we learn

about one person may not necessarily apply to others

Types of Research MethodsNaturalistic Observation

Describes the settings, frequency, and characteristics of certain behaviors in the real world

Observe in natural settings Experimenter does not interfere at all

Types of Research MethodsNaturalistic Observation Advantage

Real life situation data instead of generalized or simulated

Disadvantage Reactive Observations

Ones that interfere with the behavior being studied

Types of Research MethodsCorrelational Research

Test of whether two items are related or tend to occur together

Example: SAT/ACT Exam scores and First-year GPA

Shown as a correlation coefficient (r) Direction refers to Positive or Negative

Correlations

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5

0102030405060708090100

1 2 3 4 5

Positive Correlation + 1.00

x ↑ , y ↑ OR x ↓ , y ↓

Negative Correlation - 1.00

x ↓ , y ↑ OR x ↑ , y ↓

Correlations: 1. Studying time and

grades

2. Time spent reading and weight lost

3. Cost of a diamond and number of carats

4. Time spent eating and weight lost

a. +0.90

b. -0.08

c. +0.70

d. -0.90

Types of Research MethodsSurvey Research

Gathers data from a sample that represents a larger population

Efficient way to collect lots of information Face-to-Face interviews Telephone Written Computer

Types of Research MethodsSurvey Research

Must find a representative sample Reflects the larger population Questions must elicit meaningful and useful

responses Must check questions for cultural and personal

bias

Types of Research MethodsThe Experimental Method

Can provide cause-and-effect statements Involves manipulating variables to

determine how they affect other variables Considered most powerful research method

Types of Research MethodsThe Experimental Method

Independent variable (usually x) Variable manipulated to see effects on the

dependent variable

Dependent variable (usually y) Variable that shows the test results by reacting to

the independent variable

The Experimental Method Operational definitions

Precise definition that helps others replicate the experiment

Experimental group Participants exposed to the independent variable

Control group Participants not exposed to the independent

variable

The Experimental Method To insure reliability:

Repeat the research Control extraneous variables

Ones other than the independent variable that can influence the outcome of the experiment

Select very similar control and experimental groups

Random assignment – based on chance

Statistics and Psychology Statistics

Used to summarize, analyze, and interpret data

Descriptive and Inferential Statistics

Descriptive vs. Inferential Summarizes a set of

numbers Measure of central

tendency Mean Mode Median

Measures of variability Range Standard Deviation

Determines if ind. variable had a significant effect

Mathematical odds of of the observed behavior Does it happen by

chance?

Research Ethics Protection from harm Confidentiality Voluntary Participation Deception and Intimidation

Debriefing Researchers must explain any deception at the

conclusion of the experiment

The End