Chapter 2 and Appendix Flashcards
What is the scientific approach?
asking and answering questions about the world around us
What are the five steps of studying behaviour?
- Identify the question of interest
- Gather information and form hypothesis
- Test hypothesis by conducting research
- Analyze data, draw tentative conclusions, report findings
- Build a body of knowledge, ask further questions, conduct more research, develop and test theories
What is hindsight understanding?
relies on explanations “after the fact”
drawback: past events can be explained in many ways
What is understanding through prediction?
uses scientific method
satisfies curiosity, builds knowledge, generates principles that can be applied to new situations
What are characteristics of good theories?
- Organize information in meaningful ways
- Are testable
- Have prediction supported by research
- Conform to law of parsimony
- Simpler theory is preferred
What is a variable?
any factor that may vary
height, weight, age, GPA, eye color, reaction time, accuracy
What is an operational definition?
some variables are harder to define
operational definition is the specific procedure used to define a variable
thus the same variable can be defined in different ways across different studies
What is an independent variable?
the variable the researcher is manipulating
What is a dependent variable?
the variable the researcher is measurring
What are the pros and cons of self reports?
Pros: a way to measure a wide range of information, such as beliefs, feelings, experiences, and behavior
Cons: only reliable if reports are accurate, social desirability bias
What are overt behaviors?
response times (item detection, problem solving)
accuracy
looking rates
What is descriptive research?
identify and understand behaviors in natural settings
provides clue to cause-effect relationships
What are case studies?
in-depth analysis of individual, group, or event
What are advantages of case studies?
can study a rare phenomenon in detail
may challenge validity of current theories
can provide insights into many areas
What are disadvantages of case studies?
cannot determine case and effect
potentially poor generalizability
potentially biased data handling/analyzing
What is naturalistic observation?
observation of behavior in a natural setting
not intervening or changing the behaviors being observed
What are advantages of naturalistic observation?
provides a rich description of behavior
What are disadvantages of naturalistic obervation?
does not permit clear causal conclusions
potential bias in interpreting the observations
mere presence of observer may change the subject’s behavior
What is a representative sample?
one that reflects the important characteristics of the population
a sample composed of 80% males would not represent a student body in which only 45% are men
What is random sampling?
to obtain a representative sample
in which every member of the population has an equal probability of being chosen to participate in the survey
What is correlation research?
goal is to determine the extent to which an association exists between two variables (X and Y)
researcher measures one variable (X)
researcher measures second variable (Y)
variables are not manipulated, just measured
What is bidirectionality?
two way causality
X causes Y
Y causes X
What is spurious association?
not genuine
third variable problem
correlation due to a third variable
What is a correlation coefficient?
correlations are mathematically described by a correlation coefficient
ranges from -1.0 to +1.0
sign indicates direction
absolute value indicates strength
What is positive correlation?
variables change in the same direction
as X increases, Y increases
as X decreases, Y decreases
What is negative correlation?
variables changes in opposite direction
as X increases, Y decreases
as X decreases, Y increases
What are scatterplots?
depicts the correlation shows direction (positive or negative) of a relationship
What are advantages of correlational studies?
show the strength of relationship present
can be used to make predictions about variables
identifies “real-world” associations
What are disadvantages of correlational studies?
can’t assume a relationship exists
relationships may be due to a third unmeasured variable
shows an association NOT a cause
What are three essential characteristics of experiments?
- Manipulate one variable
- Measure whether tis variable produces changes in another variable
- Control for other factors that might influence results
What are experiments?
random assignment of participants to the different conditions
manipulation of independent variables
(some) control over extraneous variables
What is random sampling?
equal chance of someone from the population being chosen
What is random assignment?
equal chance of the same participants being assigned to any of the experimental groups
What is the manipulation of independent variables?
the variables/factors the experimenter manipulates
need to control other factors, otherwise cannot be sure whether the outcome of the experiment is due to experimental manipulation
What is between-subjects design?
some participants get one experimental manipulation, while the others gets the other experimental manipulation
What are the pros and cons of between-subjects design?
Pros: timing doesn’t matter, no practice effects
Cons: variability due to individual differences across two groups, need many more subjects
What is within-subjects design?
all participants participate in all experimental manipulations
What are the pros and cons of within-subjects design?
Pros: less random noise, fewer participants needed
Cons: carryover effects, practice, fatigue, timing may matter
What are interaction effects?
occurs when you have 2 or more independent variables each of which has at least 2 conditions
What is validity?
how well an experimental procedure actually tests what it is designed to test
What is internal validity?
degree to which conclusions are supported by the data you have
What are threats to validity?
confounding variables
demand characteristics, Placebo effect
experimenter expectancy effects
What is the placebo effect?
change behavior based on expecting a change/improvement
decreases internal validity
provides an alternative explanation for changes in experimental/treatment group
What is the experimenter expectancy effect?
unintentional ways experimenters influence participants (in direction of hypothesis)
minimized by double-blind procedure
What are descriptive statistics?
numerically describe data set (distribution of measure)
What are measures of central tendency?
mean
median
mode
quartiles
What are measures of dispersion/variation?
standard deviation
variance
range
What is a histogram?
graph of frequency distribution
scores (intervals) plotted on X axis
frequencies plotted on Y axis
a bar above each score, height of bar indicates how frequently score occured
What are non-normal distributions?
data is skewed, tilted sharply to one side or the other
mean is affected by extreme scores (outliers)
median and mode better reflect central tendency
What is dispersion/variability?
measure of how loosely or tightly bunched scores are (spread of scores)
What is the range?
simplest measure of variability
difference between highest and lowest measures
the higher the range, the less likely to find statistical significance
What is standard deviation?
measure of variability that takes into account how far each data point is from the mean
more clustering = standard deviation
What is variance?
average of squared deviation scores about the mean
What is factor analysis?
reduced a large number of correlations among many measures to a smaller number of clusters
valuable tool when identifying dimensions of behavior
What is statistical significance?
minimum level is less than 0.05
p < 0.05 in order to be statistically significant
What is a null hypothesis?
any observed differences between control and experimental group are due to chance, assumed to be true until proven wrong
What is practical significance?
real world importance
with huge sample sizes, can have statistical significance but not practical significance
