1. The Science of Psychology
Psychology: A Concise Introduction 2nd Edition
Richard Griggs
Chapter 1
Prepared by J. W. Taylor V

2. Psychology The science of behavior and mental processes
Psychologists attempt to understand
1. Observable behavior: Such as speech and physical movement
2. Mental processes: Such as remembering and thinking, which cannot be directly observed

3. The Journey… The Four Major Research Perspectives
Research Methods Used by Psychologists
How to Understand Research Results

4. The Four Major Research Perspectives
Perspectives Emphasizing Internal Factors
Perspectives Emphasizing External Factors

5. Four Perspectives Biological Behavioral Cognitive Socio- cultural
All four perspectives are complementary; they fit together like the pieces of a jigsaw puzzle to give us the complete picture.
No one perspective is “better’ than another, as each one provides information of behavior and mental processing.

6. Perspectives Emphasizing Internal Factors
Biological perspective
Views our physiological hardware (especially the brain and nervous system) as the major determinants of behavior and mental processing
Cognitive perspective
Emphasizes how our mental processes, such as perception, memory, and problem solving, work and impact our behavior

7. The Biological Perspective
There are many reasons why people get depressed
From a biological perspective, we would focus on a deficiency of activity for certain chemicals in our nervous system as the cause of this disorder, and use anti-depressant drugs to alleviate the disorder
A few weeks after starting to ingest the drugs, we feel better because mood is in part a function of brain chemistry

8. The Biological Perspective
Biological psychologists also study the involvement of the various parts of the brain and nervous system on our behavior and mental processing
For instance, vision is actually processed in the back of our heads (hence, we really do have eyes in the back of our heads,” or more precisely “the back of our brains”)

9. The Cognitive Perspective
When explaining why people become depressed, the cognitive psychology would focus on reasons such as how people explain their successes and failures
If we blame ourselves for all of our setbacks (i.e., make internal attributions), we might start to feel poorly about ourselves
However, if we realize the situation played a role in some of our setbacks (i.e., make external attributions), we might not feel so badly
Of course, it is important for students not to blame their academic failures on their teachers, because in so doing they would fail to take personal responsibility for their lives!

10. The Cognitive Perspective
Many people report problems remembering other people’s names
Often, we claim it is because we have bad memories, but is that so?
Or, is it that we never bothered to exert the mental energy required in the first place to encode other people’s names?
Both explanations may have validity, and such explanations would be of interest to a cognitive psychologist

11. Perspectives Emphasizing External Factors
Behavioral perspective
Explains that we behave as we do because of our past history of conditioning by our environment
Sociocultural perspective
Focuses on the impact of other people and culture on our behavior and mental processing

12. Behavioral Perspective
Two types of conditioning:
Classical Conditioning
Operant Conditioning
Can explain how we learn fear and other emotional responses, taste aversions, and certain other behaviors
Involves the relationship between our behavior and its environmental consequences

13. Classical Conditioning
When entering a department store, you may catch the scent of a perfume or cologne of an old boyfriend or girlfriend, and instantly be reminded of that person because during the relationship, you came to associate the scent with the person

14. Operant Conditioning
If you ask a question in class, and the teacher say “What a stupid question!” you are unlikely to ask questions in the future to avoid such an undesirable consequence
But, if the teachers prefaces his or her response to the question with “That’s an interesting question,” you may continue to ask questions in the future because of the desirable consequence of being implicitly told you are smart

15. The Sociocultural Perspective
In 1964, Kitty Genovese was brutally attacked and murdered while trying to enter her apartment building in New York City late one night. Many of the people living in the building heard her screams and cries for help, but no one called the police under after the attacker had killed her and fled more than 30 minutes later.
Subsequently, researchers devised laboratory experiments that examined how particular variables influence people’s decision whether or not to help each other.

16. Major Research Perspectives in Psychology
Major Explanatory Focus
Biological
How our physiology (especially the brain and nervous system) produces our behavior and mental processes and how genetics and evolution have impacted our physiology
Cognitive
How our mental processes, such as perception, memory, and problem solving, work and how they impact our behavior
Behavioral
How external environmental events condition our observable behavior
Sociocultural
How other people and the cultural context impact our behavior and mental processes

17. Research Methods Used by Psychologists
Descriptive Methods
Correlational Studies
Experimental Research

18. Research Methods
Correlational
Descriptive
Experimental

19. Descriptive Methods Include
Observational techniques
Case studies
Survey research
Seek to provide objective and detailed descriptions of behavior and mental processes

20. Descriptive Methods: Observational Techniques
The researcher directly observes the behavior of interest
Naturalistic observation: The behavior being observed occurs in its natural setting, without the researcher intervening in the behavior being observed.
Participant observation: The observer becomes part of the group being observed. This type of research is similar to undercover police work.

21. Naturalistic Observation
Researchers use naturalistic observation when they are interested in how humans or other animals behave in their natural environments
For instance, two well-known observational studies were done by Dian Fossey in a study of mountain gorillas in Africa, and Jane Goodall’s study of chimpanzees in Africa
This technique is also used in settings such as schools, the workplace, and bars

22. Participant Observation
In most observational studies, the observer begins the study as a participant, whether in a laboratory or a natural setting
One famous example of participant observation was conducted by Rosenhan (1973). In this study, psychologists posing as patients with symptoms of a major mental disorder were admitted to psychiatric hospitals because the doctors could not tell the psychologists from the real disordered patients. Once admitted, these “pseudopatients” acted normally and asked to be released. However, they were not released until many days later!

23. Descriptive Methods: Case Studies
The researcher studies an individual in depth over an extended period of time to attempt to learn as much as possible about the individual being studied
Often used in clinical settings to gather information that will help in the treatment of the patient
Results of case studies cannot be generalized to other people

24. Descriptive Methods: Case Studies
Case studies do allow the researcher to develop hypotheses that can be tested using experimental research
For instance, the case of H. M., who had his hippocampus removed for medical reasons at a young age, was a case study. H. M. seemed to have normal memory for information learned before the surgery, but didn’t seem to be able to form any new memories. Such a finding led to the hypothesis that the hippocampus plays an important role in the formation of new memories, which was supported by subsequent experimental research.

25. Descriptive Methods: Survey Research
Uses questionnaires and interviews to collect information about the behavior, beliefs, and attitudes of particular groups of people
It is critical to note that the wording, order, and structure of the survey questions may lead the participants to biased answers
For instance, some questions might evoke socially-desirable responses in an effort to make certain impressions on the researchers

26. Descriptive Methods: Survey Research
Another concern for survey researchers is defining the population, or the entire group of people to be studied
From that population, a representative sample, or subset of the people in the population, is surveyed
The sample must be representative of the larger relevant population so you can generalize results of the survey from the smaller sample to the larger population

27. A representative sample?
In a study of women and love, a sample was drawn mainly from women’s organizations and political groups, plus some women who requested and completed a survey following the researcher’s talk show appearances
Thus, the results (which said that women having affairs and being disenchanted in their relationships with men was typical) were not representative of the population of American women

28. Random Sampling
Each individual in the population has an equal opportunity of being in the sample
It is much like drawing names from a hat
Random sampling allows the researcher to generalize his or her findings from the sample to the larger population

29. Correlational Methods
Two variables are measured to determine if they are related
A variable is any factor that can take on more than one value (e.g., height, age, GPA, extraversion level)

30. The Correlation Coefficient
A statistic that tells us the type and the strength of the relationship between two variables
Range in value from to +1.0
The sign of the coefficient (- or +) tells us the type of relationship, positive or negative

31. Positive Correlation
A positive correlation indicates a direct relationship between two variables, with low scores on one variable tending to be paired with low scores on the other variable, and high scores on one variable tending to be paired with high scores on the other variable
For instance, SAT scores and first-year college GPA tend to be positively correlated
A person’s height and weight also tend to be positively correlated

32. Negative Correlation
A negative correlation is an inverse relationship between two variables, with low scores on one variable tending to be paired with high scores on the other variable
For instance, there is a negative correlation between how much time a student watches TV and his or her grades in school
Mountain elevation level and temperature are also negatively correlated

33. Strength of Relationship
The second part of the correlation coefficient is its absolute value, which ranges from 0 to 1
Zero and absolute values near zero indicate no relationship
As the absolute value increases toward 1.0, the strength of the relationship increases
It is critical to note that the sign of the coefficient tells us nothing about the strength of the relationship

34. Scatterplots A scatterplot is a visual depiction of correlational data
On the X axis are scores on one variable; on the Y axis are scores on the second variable
Each data point in the scatterplot is a person’s scores on each of the two variables

40. The Third-Variable Problem
Strong correlations give us excellent predictability, but they do not allow us to draw cause-and-effect conclusions about the relationships between the two variables
The third-variable problem occurs when a third, unmeasured variable is responsible for the relationship observed between the two measured variables
For example, the length of time a man is married is negatively correlated with the amount of hair on his head
Does this mean that being married longer causes a man’s hair to fall out?

41. Experimental Research
The key aspect of experimental research is that the researcher controls the experimental setting
It is this control that allows the researcher to make cause-and-effect statements about the experimental results

42. Experimental Control
First, the experimenter controls for the influence of possible third-variables by making sure that they are held constant across all of the experimental groups/conditions
Second, the experimenter controls for any possible influence due to the individual characteristics of the participants, such as intelligence, by using random assignment, which is randomly assigning the participants to groups in an experiment to equalize participant characteristics across the various groups in the experiment

43. Designing an Experiment
When a researcher designs an experiment, the researcher begins with a hypothesis about the cause-and-effect relationship between two variables
One of the variables is assumed to be the cause, and the other variable is the one to be affected
The independent variable is the hypothesized cause, and the experimenter manipulates it
The dependent variable is the variable that is hypothesized to be affect by the independent variable and thus is measured by the experimenter

44. Designing an Experiment
The simplest of experiments is one with two groups, in which participants are randomly assigned to one of the groups
One of the groups will be exposed to the independent variable, and the other group will not be
The group exposed to the independent variable is called the experimental group
The group not exposed to the independent variable is called the control group

45. For example…
If the hypothesis is that aerobic exercise reduces anxiety, then the independent variable to be manipulated is aerobic exercise, and the dependent variable will be anxiety level
The experimental group will participate in some aerobic exercise program, and the control group will not
The experiment must measure the anxiety levels for the groups at the beginning of the study before the independent variable is manipulated and then again after the manipulation
If the two groups are truly equivalent, the average anxiety level for each group at the start of the study should be the same
If aerobic exercise does reduce anxiety, then we should see this difference in the second measurement at the end of the experiment

46. The Placebo Group
In addition to the experimental and control groups, we need to add a placebo group to improve the experiment
A placebo group is a group of participants that believes they are receiving treatment but are not
They receive a placebo, a harmless pill that has no active ingredients
For example, this group would be told they are getting an anti-anxiety drug, but they would only get a placebo

47. The Placebo Group
The placebo effect is improvement due to the expectation of improving because of receiving treatment
The reduction of anxiety in the experimental group participants may, in fact, be partially or completely due to a placebo effect
To conclude that the reduction of anxiety in the experimental group was not due to a placebo effect, it would have to be significantly greater than that observed for the placebo group

48. Inferential Statistical Analyses
Indicate the probability that the results of a study are due to random variation (chance)
Of course, the researchers would want this probability to be low
In statistics, a “significant” finding is one that has a probability less than 0.05 (1/20) that it is due to chance
Thus, a significant finding is one that is not likely due to chance

49. The Double-Blind Procedure
A control measure in which neither the experimenter nor the participants know which participants actually got the treatment and or got the placebo
Controls for experimenter expectations
If the experimenter knew which condition the participants were in, then s/he might unintentionally treat them differently and thereby impact their behavior

50. Summary of Research Methods

51. How to Understand Research Results
Descriptive Statistics
Frequency Distributions

52. Descriptive Statistics Inferential Statistics
Types of Statistics
Descriptive Statistics
Used to describe the data of a research study in a concise fashion
Inferential Statistics
Indicate the probability that the results of the study are due to random variation

53. Descriptive Statistics
Two types of descriptive statistics
Measures of central tendency
Measures of variability
A researcher will also often examine a frequency distribution, which depicts in a table or graph, the number of participants receiving each score for a variable

54. Measures of Central Tendency
Designed to summarize a set of data with a single number
Three measures of central tendency
1. The mean is the numerical average for a distribution of score
2. The median is the score that is positioned in the middle of the distribution of scores when scores are listed from lowest to highest
If there is an odd number of scores, the median is the middle score
If there is an even number of scores, the median is the average of the two center scores
3. The mode is the most frequently-occurring score in a distribution of scores
If two scores occur with equal frequency, both can be the mode

55. About the Mean…
The mean is the most commonly used measure of central tendency because it is used to analyze data in many inferential statistical tests
However, the mean, because it uses all scores in its computation, can be distorted by extremely high or extremely low scores

56. Measures of Variability
Designed to provide an idea of how scattered a set of scores tends to be
Two measures of variability
1. The range is the difference between the highest and lowest scores in a distribution of scores
Like the mean, the range can be greatly distorted by extremely high or extremely low scores
2. The standard deviation is the average extent to which the scores vary from the mean of the distribution
A small standard deviation means that scores do not vary very much from the mean
A larger standard deviation means that scores tend to vary greatly from the mean

57. Summary of Descriptive Statistics

58. Frequency Distributions
Organizes the data in a score distribution so that we know the frequency of each score
Types of distributions
Normal Distributions
Skewed Distributions

59. Normal Distributions
The mean, the median, and the mode are all equal because the normal distribution is symmetric about its center
The percentage of scores falling within a certain number of standard deviations of the mean is set
About 68% of the scores fall within 1 standard deviation of the mean
About 95% fall within 2 standard deviations of the mean
More than 99% fall within 3 standard deviations of the mean
It is these percentages that give the normal distribution its bell shape

60. The Normal Distribution

61. Normal Distributions with Different Standard Deviations

62. Percentile Rank
The percentage of scores below a specific score in a distribution of scores
For instance, the percentile rank of a score that is 1 standard deviation above the mean is roughly 84%
Note that you can never have a percentile rank of 100% because it is impossible to outscore yourself
You can, however, have a percentile rank of 0% if you have the lowest score in the distribution

63. Skewed Distributions Are asymmetrical in shape
A right-skewed (also called positively skewed) distribution is a frequency distribution in which there are some unusually high scores, but most scores tend to be low
A left-skewed (also called negatively skewed) distribution is a frequency distribution in which there are some unusually low score, but most scores tend to be high

64. Sample Skewed Distributions

65. Skewed Distributions
Because unusually high or low scores distort a mean, such distortion occurs for the means of skewed distributions
The mean for a right-skewed distribution is distorted toward the tail created by the few high scores and so is greater than the median
The mean for a left-skewed distribution is distorted toward the tail created by the few low scores and so is less than the median
Consequently, when you have a skewed distribution, you should use the median because atypical scores in the distribution do not distort the median