Human intuition is remarkably accurate and free from error. 3
Most people seem to lack confidence in the accuracy of their beliefs. 4
Case studies are particularly useful because of the similarities we all share. 5
We tend to overestimate the number of people who share our attitudes and beliefs. 6
The opinions of 1500 randomly selected people can provide a very accurate picture of the opinions of an entire nation. 7
Research suggests that college students spend more than 25% of their waking hours in conversation. 8
The scientific finding that children who watch violence on TV tend to be violent proves that viewing violence causes it. 9
The purpose of the experiment is to re-create behaviors exactly as they occur in everyday life. 10
As a science, psychology is objective and valuefree. 11
States with the death penalty have lower homicide rates. 12
Technique using tools such as observation, experimentation, and statistical analysis to learn about the world Through its use, psychology is thereby considered a science.
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Theories & Hypotheses Theory: An explanation using an integrated set of principles that organizes and predicts observations Hypothesis: A testable prediction; often implied in a theory
Research: method of asking questions then drawing logical supported conclusions Researchers need to be able to determine if conclusions are reasonable or not (critical thinking).
Abraham Lincoln is the best president the United States has ever had Laughter is the best medicine The best things in life are free Shakespeare s Macbeth is a better play than Romeo & Juliet There is a genetic predisposition to schizophrenia Attitudes affect cancer 2+2=4
Conclusions based solely on personal experience and sensible logic Can lead to incorrect conclusions
Observation: Gathering of information by simply watching subjects Can lead to bias as observations may be influenced by what you want to discover
Naturalistic observation: Method of observation where subjects are observed in their natural environment Subjects are not aware they are being watched Could use hidden cameras or two way mirrors
For example, we could compare the grades of students who wore headphones during studying and who did not or count specific behaviors, like how many pages a student reads in 10 minutes *Methods could have flaws-just because you turn the page doesn t mean you learn anything
Bias: situation in which a factor unfairly increases the likelihood of a researcher reaching a particular conclusion Bias should be minimized as much as possible in research
Researcher bias: the tendency to notice evidence which supports one particular point of view or hypothesis Objectivity tends to reduce bias by relying less on the observers opinion
Participant bias: tendency of research subjects to respond in certain ways because they know they are being observed The subjects might try to behave in ways they believe the researcher wants them to behave Can be reduced by naturalistic observation
Critical thinking: smart thinking Critical thinking does not accept arguments and conclusions blindly It examines assumptions, discerns hidden values, evaluates evidence and assesses conclusions based on well supported evidence 27
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1. What am I being asked to believe or accept? 2. What evidence is available to support the assertion? 3. Are there alternative ways of interpreting the evidence? 4. What additional evidence would help evaluate the alternatives? 5. What conclusions are most reasonable? 29
Case study: In depth study of one individual with the hopes of determining universal principles of behavior This technique is very open to bias Difficulty of applying data from one person to everyone For example: an in-depth study of just one headphone wearing student in study hall could provide some very unrepresentative results
Sometimes, a case study is all that is ethically possible For example, child abuse, is usually researched with case studies It would be unethical for researchers to abuse children, so they must wait until authorities discover a case and then attempt to study the effects of the abuse
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1: a case study may be used as a source of insights and ideas, particularly in the early stages of investigating a specific topic. Freud s theory of psychoanalysis from case studies of therapy clients Piaget s theory of cognitive development from case studies of his own children. 2: case studies may be used to describe particularly rare phenomena. The study of presidential assassins is necessarily limited to case studies of a few people who have killed or tried to kill U.S. presidents. 3: case studies in the form of psychobiographies involve the application of psychological concepts and theories in an effort to understand the lives of famous people, such as da Vinci, Martin Luther, Mahatma Gandhi, Nathaniel Hawthorne, and Richard Nixon. Sometimes the investigator attempts to explain the person s entire life; in other cases, he or she studies only specific aspects of the person s behavior 4: case studies provide illustrative anecdotes. Researchers and teachers often use case studies to illustrate general principles to other researchers and to students.
1: they are virtually useless in providing evidence to test behavioral theories or treatments. The lives and events studied occur in uncontrolled fashion and without comparison information. No matter how reasonable the investigator s explanations, alternative explanations cannot be ruled out. 2: most case studies rely on the observations of a single investigator. we often have no way of assessing the reliability or validity of the researcher s observations or interpretations. one must always be concerned about self fulfilling prophecies and demand characteristics.
What are the advantages and disadvantages of case studies?
Think about how many times it s useful to know the extent to which two variables are related Is there a relationship between diet and exercise? Between communication styles and divorce? Between training techniques and success in the Olympics?
The research technique to answer such questions is the correlational study Correlational study: Research study designed to determine the degree to which two variables are related to one another Correlation does not mean causation
Important NOT to imply a cause and effect relationship between the variables Correlational studies do not determine why the two variables are related--just that they are related Correlational studies are helpful in making predictions
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Scatterplot is a graph comprised of points that are generated by values of two variables. The slope of the points depicts the direction, while the amount of scatter depicts the strength of the relationship 41
As the value of one variable increases (or decreases) so does the value of the other variable A perfect positive correlation is +1.0 The closer the correlation is to +1.0, the stronger the relationship
As the value of one variable increases, the value of the other variable decreases A perfect negative correlation is -1.0 The closer the correlation is to -1.0, the stronger the relationship
A correlation is positive if two sets of scores, such as weight and height, tend to rise or fall together A correlation is negative if two sets of scores relate inversely, one set goes up as the other goes down 44
If effectiveness of studying increases when students wear headphones, we can say that the two variables are positively correlated That is, both variables increase or decrease together
If studying effectiveness decreases when students wear headphones, and increases when they do not wear headphones, the variables are negatively correlated- one variable increases while the other decreases
There is NO relationship whatsoever between the two variables
Why can t we conclude cause and affect relationships from correlational data?
SURVEYS
Why should we be cautious of data obtained from surveys? Survey Method: Research method that relies on self-reports; uses surveys, questionnaires, interviews Usually a very efficient and inexpensive method
Surveys are seductively efficient Simple to create and inexpensive but don t consider how easy bias occurs For example, question wording Do you like flowers? Do you like horticulture? For example, social desirability: People may try to please the researcher by answering the way they think they should
68% roll toilet paper over the spool 79% squeeze the toothpaste from the top 7% look behind the shower curtain when using someone else s bathroom 80% eat corn on the cob in circles rather than from side to side *Results based on responses from a sample of only 7000 of 25,000 who took received survey. 60
Assume you have carefully designed your questions to avoid bias You still must be sure your survey results will be relevant to the large group, known as the population, that interests you Population: The total large group being studied from which a sample is drawn for a study
Random Sample: A sample that represents a population fairly: (unbiased) Each member of the population has an equal chance of being included If a sample is not random it is said to be biased
Random Sample: randomization helps make a sample representative Representative Sample: when a group is chosen randomly and every person in that population of people has an opportunity to be picked, the sample represents the population Population: results gained from studying the sample can be generalized to the population at large 64
Psychologists who study how individuals change throughout their lifetime Often use longitudinal and cross-sectional studies to see how individuals change throughout the life span
Longitudinal Study: Developmental study where researchers study the same group of individuals for many years -Provide a rich source of data as time passes but can be very expensive and difficult to conduct -Tend to be rare
Cross-Sectional Study: Developmental study where researchers simultaneously study a number of subjects from different age groups and then compare the results More efficient, cheaper, easier than longitudinal studies, but group differences may be due to factors other than development.
Observation, case studies, correlational studies, surveys, longitudinal, and crosssectional studies are important research techniques Most psychologist use these techniques in combination
What are the advantages and disadvantages of longitudinal and crosssectional studies?
For establishing cause and effect, there is only one game in town- EXPERIMENTS The Experiment is the only method that allows us to draw conclusions about cause and effect relationships.
What is the only method that allows us to draw conclusions about cause and effect relationships?
A Theory is an explanation that integrates principles and organizes and predicts behavior or events By organizing isolated facts, a theory simplifies things, like a useful summary For example, low self-esteem contributes to depression. If we were to observe that depressed people talk about their past, present, and future in a gloomy manner, we may theorize that low-self-esteem contributes to depression 75
A Hypothesis is a testable prediction, often prompted by a theory, to enable us to accept, reject or revise the theory Such predictions give direction to research, they specify what results would support the theory and which would disconfirm it Example: People with low self-esteem are apt to feel more depressed 76
Operational Definition: A statement that defines the exact operations or methods used in research Such carefully worded statements should allow others to replicate (repeat) the original observations Variable: Factor or characteristic that is manipulated or measured in research
Dependent Variable: behavior that researchers are looking for. Look for the behavior that is occurring in the experiment to identify this variable Independent Variable: is what causes the behavior to happen. After finding the dependent variable, ask- what caused this behavior?
The IV is the cause because the IN-dependent variable is Introduced Into the experiment The DV is the effect because it depends on it
What is the difference between the independent variable and the dependent variable in an experiment?
Typical experiments have at least two groups- 1. Experimental group 2. Control group
Are not exposed to the independent variable Results are compared to those of the experimental group Also called the control condition
Experimental Group: all students assigned to wear headphones Control Group: all students assigned not to wear headphones These two groups will permit us to compare the effect of headphones on two groups of similar students
Assigning participants to the control and experimental groups by chance Each participant should have an equal chance of being assigned into either group
Random sampling in surveys and random assignment in experiments are NOT the same! Random sampling helps us generalize to a larger population. Random assignment controls extraneous influences, which helps us infer cause and effect. 87
Any differences in the experiment s conditions--between the experimental and control groups Differences include temperature, lighting, noise levels, distractions, etc. Ideally, there should be a minimum of environmental differences between the two groups
Any changes in an experiment s results due to the subject anticipating certain outcomes to the experiment
An experimental procedure where the research participants are ignorant (blind) to the expected outcome of the experiment Sometimes called single blind procedure It is important when those collecting data are asked to make judgments about the DV because they could be influenced by their own expectations
An experimental procedure where both the research participants and those collecting the data are ignorant (blind) to the expected outcome of the experiment Used to control for the effects of expectation as a confounding variable
Researchers use a special kind of control, a placebo, to deal with expectations in some experiments (including all drug studies) A non-active substance or condition administered instead of a drug or active agent Given to the control group
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Run the experiment and collect the data Analyze numbers, using statistics, to see if hypothesis is supported Average end of quarter grade for the experimental groups was a B and for the control group it was a C Is this enough difference to conclude that there is a cause and effect relationship? What if the difference was between a B and B-? How different must the values of the DV be for the two groups? Statistical significance can determine this
Statistically Significant: Possibility that the differences in results between the experimental and control groups could have occurred by chance is no more than 5 percent Must be at least 95% certain the differences between the groups is due to the independent variable
What do we mean when we say that experimental results must be replicable, and why is that important? Replication: Repeating the experiment to determine if similar results are found If so, the research is considered reliable. If an experimental result can only be attained once, we must conclude it was caused by some chance variable and there is no cause and effect relationship
Participants must be informed, in advance, about: the general nature of the research, and any potential risk. Participants must have the right to refuse participation or withdraw at any time.
Studies involving harm or discomfort may be conducted only under certain circumstances, and only with the informed consent of the participants.
Individual data about research participants should never be discussed or released.
Participants have a right to receive a complete explanation of the research at the end of the study. This is extremely important if the research involves deception.