Chapter 2- Methods Flashcards
hindsight bias
people have the tendency upon hearing research findings (and many other things) to think that they knew it all along
applied research
research that has clear practical applications
basic research
research that explores questions that are of interest to psychologists but is not intended to have immediate, real-world applications
hypothesis
expresses a relationship between two variables
dependent variable
depends on the independent variable
independent variable
manipulated by the researchers, effects the dependent variable
theory
aims to explain some phenomenon and allows researchers to generate testable hypotheses with the hope of collecting data to support the theory
operational definition
an explanation of how you will measure a variable
validity
measures what it set out to measure
reliability
can be replicated, consistent
sampling
the process by which participants are selected for research
sample
the group of participants
population
includes anyone or anything that could possibly be selected to be in the sample
representative sample
representative of the characteristics of the larger population
random sampling
every member of the population has an equal chance of being selected, best done using a computer, a table of random numbers, or picking names out of a hat
stratified sampling
a process that allows a researcher to ensure that the sample represents the population on some criteria
laboratory experiment
experiments conducted in a laboratory, a highly controlled environment
field experiment
experiments conducted out in the world
confounding variables
any difference between the experimental and control conditions, except for the independent variable, that might affect the dependent variable
participant-relevant confounding variables
differences between the experimental and control groups that are due to the participants (ex. they choose which group to be in)
situation-relevant confounding variables
differences between the experimental and control groups that are due to the situational differences (to control these, the situation must be the same for all participants)
random assignment
each participant has an equal chance of being placed in to any group
controls
making everything in an experiment the same except for the independent variable
group-matching
a process used to ensure that the experimental and control groups are equivalent on some criterion
experimenter bias
the unconscious tendency for researches to treat members of the experimental and control groups differently to increase the chance of confirming their hypothesis, not a conscious act
double-blind procedure
occurs when neither the participants nor the researcher are able to affect the outcome of the research
single-blind procedure
occurs when only the participants do not know to which group they have been assigned
response or participant bias
the tendency for subjects to behave in certain ways (i.e. circle the midpoint on a scale or pick the right-handed option more than the left-handed option)
social desirabliity
the tendency for subject to try to give answers that reflect well upon them
Hawthorne effect
merely selecting a group of people on whom to experiment has been determined to affect the performance of that group
placebo method
when participants in the experimental group receive a drug and participants in the control group are given an inert but otherwise identical substance
correlations
expresses a relationship between two variables without ascribing cause
negative correlation
the presence of one thing predicts the absence of the other
positive correlation
the presence of one thing predicts the presence of the other
survey method
involves asking people to fill out surveys
response rate
the number of people who answer and return a survey
naturalistic observation
observing participants in their natural habitats without interacting with them at all
case study method
used to get a full, detailed picture of one participant or a small group of participants
descriptive statistics
statistics that describe a set of data
frequency distribution
a organization of data that tells you how many of each dependent variable option there was
measures of central tendency
attempt to mark the middle of a set of data (mean, median, mode)
mean
the average of all the scores in a distribution, add up all the data and divide by the total number of data points
median
the central score in the distribution, write the data down in order and pick the data point in the middle
mode
the score that appears the most frequently
extreme scores or outliers
data points that are significantly larger or smaller than the rest of the data
positive skew
when a distribution contains an extreme score that is very high, the mean is higher than the median
negative skew
when a distribution contains an extreme score that is very low, the mean is lower than the median
measures of variablitity
descriptive statistical measures that attempt to describe the diversity of the distribution
range
the distance between the highest and lowest scores
standard deviation
the square root of the variance, relates the average distance of any score in the distribution from the mean
variance
relates the average distance of any score in the distribution from the mean
z score
a measure of the distance from a score to the mean in units of standard deviation (0=mean, +2=2 SD above the mean, -2=2 SD below the mean)
normal curve
a theoretical bell shaped curve for which the area under the curve lying between any two z-scores has been predetermined, 68% fall within 1 SD, 95% fall within 2 SD, 98% fall within 3 SD
correlation coefficient
a statistic that computes the strength of a correlation (+1=perfect positive correlation, -1=perfect negative correlation, 0=no correlation)
scatter plot
a graph of a correlation using data points on an x,y coordinate plane
line of best fit/regression line
the line drawn through the scatter plot that minimizes the distance of all the points from the line, slope indicates correlation
inferential statistics
used to determine whether or not findings can be applied to the larger population from which the sample was selected
sampling error
the extent to which the sample differs from the population
p value
gives the probability that the difference between the two groups is due to chance, must be less than 0.05 in order to be considered statistically significant
statistical significance
p value is less than 0.05
institutional review board (IRB)
an ethics board of an institution of research, reviews research proposals for ethical violations and/or procedural errors, must approve a research project before researchers can begin collecting data
coercion
participation must be voluntary
informed consent
participants must know that they are involved in research and give their consent
anonymity
participants’ privacy must be protected, researchers do not collect any data that allows them to match a person’s responses with his or her name
confidentiality
participants’ privacy must be protected, the researcher guarantees that they will not identify the source of any of the data
debriefing
participants should be told about the purpose of the study and provided with ways to contact the researchers about the results
counterbalancing
using participants as their own control group
percentiles
indicate the distance of a score from 0
risk
participants can not be placed at significant mental or physical health risk
