research methods 1 & 2 Flashcards
a general set of ideas about the way that the world works
theory
a particularly dramatic change in our way of thinking
paradigm shift
evidence gathered from others or self experience
anecdotal evidence
scientific tool used to measure the effect of one variable on another
experiment
Variable manipulated by the scientist. Ex: amount of enzyme present
independent variable
Variable being observed by the scientist. Ex: amount of cell growth
dependent variable
Manipulating the independent variable within each participants to minimize the effect of external variables on the dependent measure
within-subjects design
Improved performance over the course of an experiment due to becoming more experienced
practice effect
one group acts as the control group
between subjects design
A variable other than the independent variable that has an effect on the results
confounding variable
general group of people we are trying to learn about
population
selected members of the population
sample
assigning subjects to either the experimental or control group at random to avoid any biases that may cause differences between the groups of subjects
Random Assignment
effect that occurs when an individual exhibits a response to a treatment that has no related therapeutic effect
the placebo effect
when a participant’s action in an experiment influence the results outside of the manipulations of the experimenter
participant bias
When participants do not know whether they belong to the experimental or control group, or which treatment they are receiving
blinding
Experiments in which neither the experimenter nor the participants know which group each participant belong to
double-blind studies
type of graph used to report the number of times groups of values appear in a data set
histogram
type of graph illustrating the distribution of how frequently values appear in a data set
frequency distribution
a distribution with a characteristic smooth, bell and symmetrical-shaped curve around a single peek
normal distribution
the average value of a data set
mean
extreme points, distant from others in a data set
outliers
the value that appears most frequently in the set
mode
the centre value in a data set when the set is arranged numerically
median
is a measure of the average distance of each data point from the mean
standard deviation
statistics that allow us to use results from samples to make inferences about overall, underlying populations
inferential statistics
A statistical test that considers each data point from both groups to calculate the probability that 2 samples were drawn from the same population.
T-Test
a value expressing the probability calculated by the t-test
P-value
greater than 5% probability of obtaining the data by chance
not signtificant
less than 5% probability of obtaining the data by chance (0.05)`
significant
when the difference between 2 groups is due to some true difference between the properties of the 2 groups and not simply due to random variation
statistical significance
A measure of the strength of the relationship between 2 variables.
correlation
measures the degree with which 2 variables are correlated; symbolized by the letter r.
correlation coefficient
+1; as one variable increases, the other variable also increases
positive correlation
-1; As one of the variables decreases, the other variable decreases
negative correlation
a feature or quality that always takes the same value across all situations
constant
the extent to which there is evidence that a test measures a particular hypothetical construct
construct validity
a group of individuals designed to serve as an accurate comparison in an experiment
control group
statistics designed to describe the data collected. Includes mean, median and standard deviation.
descriptive statistics
the philosophical perspective that states that knowledge should be gained by direct observation of the world as it is, as opposed to rational perspectives that used logic and reason to determine how the world ought to be
Empiricism
the participants in the study who receive the manipulation in regard to the independent variable.
experiment group
actions made by the experimenter, unintentionally or deliberately, to promote the result they hope to achieve.
experimenter bias
a variable that the researcher did not manipulate or measure, but that nonetheless could still affect the outcome of the experiment.
extraneous variable
A research tool during which the investigator asks the participant questions, often these may be structured or semi-structured in nature.
interview
different perspectives that emphasize different aspects of a research question.
levels of analysis
descriptive statistical technique for summarizing a distribution of data into a single value that represents the entire population.
measures of central tendency
a descriptive research method in which the researcher engages observation of behavior in real-world settings
naturalistic observation
a standardized measure of a sample of a person’s behavior ex. IQ
psychological test
data collected from a study that has yet to be assessed using statistical analysis
raw data
• the measurement consistency of tests
reliability
the repetition of a study to see whether the earlier results can be duplicated
replication
a tendency to give socially approved answers to questions about oneself.
social desirability bias
