AP Psychology
Unit 1 Review
Overview
o Hindsight Bias
 Upon hearing research findings, the tendency to believe that you knew it all
along
o Applied Research
 is one type of research that is used to answer a specific question that has
direct applications to the world.
 This is the type of research that solves a problem.
o Basic Research
 Is a type of research that is driven purely by curiosity and a desire to expand
our knowledge.
 Not intended to have immediate real world applications
Research
o Hypothesis
 Expresses a relationship between two variables
o Variables
 The dependent variable, the variable researchers are collecting data on.
 The independent variable is the variable that is manipulated or changed by
researchers
 Confounding variable are variables that can affect the outcome that the
researcher doesn’t control
o Theory
 Aims to explain some phenomenon
 Allows researchers to generate testable hypotheses with the hope of
collecting data that support the theory
o Operational Definitions (very important in Psychology)
 Explanations of how variables will be measured
o Validity and Reliability
 Research is valid when:
 it measures what the researcher set out to measure
 it is accurate
 Research is reliable when:
 it can be replicated
 it is consistent
o Participants (Subjects)
 The individuals on which the research will be conducted
o Sampling
 The process by which participants are selected
o Sample
 The group of participants
o Random Selection
 Every member of the population has an equal chance of being selected
 Increases the likelihood of a representative sample
 Allows researchers to generalize about their results
Experimental Method
o Experiment
 Only way to show a cause-effect relationship
 Preferred research method
o Laboratory Experiments
 Conducted in a lab
 Advantage- highly controlled
o Field Experiments
 Conducted out in the world
 Advantage- more realistic
o Confounding Variables
 Outside factors that can affect the results of an experiment
o Assignment
 The process by which participants are put into the experimental or control
group
o Random Assignment
 Each participant has an equal chance of being placed into any group
 Minimizing preexisting differences between groups
o Experimenter Bias
 The unconscious tendency for research members to treat members of the
experimental and control groups differently to increase the chance of
confirming the hypothesis
o Double-Blind Procedure
 Neither the participants nor the researcher are able to affect the outcome of
the research
 Eliminates experimenter and subject bias
o Single Blind
 The subjects don’t know to which group they’ve been assigned
 Minimizes the placebo effect
o Experimental Group
 Gets the treatment in the experiment
o Control Group
 Does not receive the treatment in the experiment
 Without this, knowing the effects of the experimental treatment is impossible
o Placebo Effect
 Is defined as an unconscious phenomenon in which some people experience a
benefit after the administration of an inactive "look-alike" substance or
treatment
 giving the control group an inert drug
Descriptive Research Methods
o Correlations
 Express a relationship between two variables
 Positive
 the presence of one predicts the presence of the other
 Negative
 the presence of one predicts the absence of the other
 Do not imply causation
o Survey Method
 Asking people to fill out surveys
 Investigates relationships, but not causation
 No independent or dependent variables
 Response rate
 Varies by people who send the survey back
o Naturalistic Observation
 Observe participants in their natural habitats without interacting with them
 Control is sacrificed
 Goal
 to get a realistic and rich picture of the participants’ behavior
o Case Study
 Used to get a full, detailed picture of one participant or a small group of
participants
 Findings can’t be generalized to a larger population
 Often used to research clinical disorders, and brain injury effects
Descriptive Statistics
o Central Tendency
 Mean, median, mode
 Mean most common, but most affected by outliers/extreme scores
o Measures of Variability
 Depict the diversity of a distribution
 Range
 The difference between the highest and lowest scores in a distribution
 Standard deviation
 relate the average distance of any score in the distribution from the
mean
 the higher the range, the more spread out the distribution
 the lower the range, the less spread out the distribution
 Normal curve
 one standard deviation from the mean- 68% of scores
 two standard deviations- 95%
 three standard deviations- 99.7%
Correlations
o Correlation Coefficient (r)
 Range from -1 to +1
 -1 = perfect negative correlation
 +1 = perfect positive correlation
 0 = weakest possible correlation
 +/- = direction of the variables with each other
 - = variables in opposite direction of each other
 + = variables in same direction with each other
o Scatter Plot
 Correlations can be graphed using a scatter plot
 Line of best fit (regression line)
 drawn through it
Inferential Statistics
o Purpose
 To determine whether findings can be applied to the larger population from
which the sample was selected. Is the difference shown in data collection
significantly different?
o Tests
 ANOVAs, MANOVAs, t-tests
 Consider the magnitude of difference and size of sample
 Yield a p-value
 the smaller, the more significant the results
 p = .05 is the cut off for statistically significant results
o 5% chance that results occurred by chance alone
APA Ethical Guidelines
o Institutional Review Board (IRB)
 Any type of academic research must first propose the study to this ethics
board
o Animal Research: Requirements for Psychological Studies
 They must have a clear scientific purpose
 research must answer a specific and important scientific question
o animals chosen must be best suited to answer it
 Must care for and house animals in a humane way
 Must acquire animal subjects legally
 purchased from accredited companies
 trapped in a humane way
 Must design experimental procedures that employ the least amount of
suffering feasible
o Human Research
 Coercion
 participation must be voluntary
 Informed consent
 participants must know that they are involved in research and give
consent
 no extreme deception about the nature of the study
 Anonymity/confidentiality
 identity and actions of participants can’t be revealed
 can’t identify participants as the source of any of the data
 Risk
 participants can’t be placed at significant mental/physical risk
 Debriefing procedures
 participants must be told the purpose of the study and provided with
ways to contact the researchers about study results