Chapter 2 Flashcards
Mode
The value of the most frequently observed measurement
Mean
The average value of all the measurements
Median
The value that is found in the “middle”
Range
The value of the largest measurement in a frequency distribution minus the value of the smallest measurement
Standard deviation
A statistic that describes the average difference between the measurements in a frequency distribution and the mean of that distribution
Correlation
Two variables are said to be correlated when variations in the value of one variable are synchronized with variations in the value of the other
Positive correlation
Both variables increase or decrease together
Negative correlation
As one variable increases, the other decreases
Correlation coefficient
A measure of the direction and strength of a correlation (r). Ranges from -1 to 1.
Natural correlation
Correlations that we observe in the world around us
What can correlation not tell us?
Causality or directionality
Third variable correlation
Two variables are correlated only because each is causally related to a third variable.
Matched Samples Technique
Participants in two groups are identical in terms of a third variable
Matched Pairs Technique
Each participant is identical to one other participant in terms of a third variable
Experiment
A technique for establishing the causal relationship between variables through manipulation of one of the variables
Allows us to rule out the influence of other variables
Self-selection
A problem that occurs when anything about a person determines whether he or she will be included in the experimental or control group
Random assignment
Uses a random event to assign people to the experimental or control group.
When can the results of an experiment be considered statistically significant?
If there is a less than 5% chance that our random assignment has failed (p < 0.05)
Case method
Method of gathering scientific knowledge by studying a single individual (n=1)
Random sampling
a technique for choosing participants that ensures that every member of a population has an equal change of being included in the sample
What did the standardization of ethics (Nurembourg Code and Declaration of Helsinki) come in the wake of?
human experiments done by Nazi doctors
Tuskegee Experiment
399 African American men with syphilis were denied treatment to observe the progression of the disease
What was the purpose of Milgram’s study of obedience?
Measured the willingness of study participants to obey an authority figure who instructed them to perform acts that conflicted with their personal conscience
Describe Milgram’s study of obedience
- The experimenter (E) orders the teacher (T), the subject of the experiment, to give what the latter believes are painful electric shocks to a learner (L), who is actually an actor and confederate.
The subject believes that for each wrong answer, the learner was receiving actual electric shocks, though in reality there were no such punishments.
