In science, a(n) _________ is formulated based on observation and insights, and consists of a series of tentative premises about ideas and concepts that lay the foundation for empirical research about a phenomenon.
THEORY
What defines a "true experiment"?
True experiments are defined by random assignment to experimental conditions and experimental control.
What is the difference between a sample and a population?
A population is the collection of people / units that you are interested in generating conclusions. The sample represents the actual participants included in the study.
What is the key difference between an independent variable and dependent variable?
In an experiment, an independent variable is the variable that is experimentally manipulated. The dependent variable is the measured outcome. The independent variable is thought to have a causal impact on the dependent variable.
___________ is achieved if the probability (p) of obtaining the observed effect by chance is small (usually p < .05).
STATISTICAL SIGNIFICANCE
In science, a(n) _________ is a testable directional prediction about specific relationships in a study.
HYPOTHESIS
What is the primary benefit of an experimental design relative to a non-experimental design?
Experimental designs allow for researchers to establish cause and effect relationships between two variables (X -> Y).
What is a power analysis?
A power analysis is a calculation completed before data is collected to determine the the sample size needed to achieve adequate statistical power.
Statistical power is the probability of obtaining a statistically significant effect, if that effect actually exists.
The ___________ of a variable involves translating an abstract theoretical concept into a concrete specification of procedure and measure, so that it may be observed, recorded, and replicated.
OPERATIONALIZATION
TRUE OR FALSE: Effect size and statistical significance are the same thing. Explain.
FALSE. Statistical significance tells us if we can assume that there is an effect or not (it tells us nothing about the size of the effect). An effect size indicator tells us more about the potential magnitude of the effect.
What is the purpose of a literature review?
The purpose of a literature review is to introduce a topic, review the existing knowledge on a particular topic, identify key themes, and identify gaps in the literature that could motivate future research.
If you see the language 2 x 2 design what does that mean?
It means that there are two independent variables that are "crossed" within a study. The first independent variable has 2 levels and the second independent variable has 2 levels. Together they cross to create four experimental conditions.
What is Mechanical Turk (MTurk)?
Amazon Mechanical Turk (MTurk) is a crowdsourcing too that allows researchers to pay online workers to complete research studies.
What is the key difference between measurement reliability and measurement validity?
Reliability is the consistency of a measurement.
Validity is the extent to which the tool measures what it is intended to measure.
If you see the following result, "t(100) = 4.15, p < .001, d = 0.32" what is the best interpretation?
p < .001. The effect is statistically significant.
d = 0.32. This is a small to medium effect.
What is meant by the phrase "gap in the literature"?
When building the rationale for why more research is needed on a particular topic, a researcher will typically review existing research and then identify ways that the existing research is limited in being able to answer a particular research question. These limitations are sometimes called "gaps in the literature".
________ validity is the extent that inferences of causality can be made about the obtained relationship between the independent variable and the dependent variable (Crano, Brewer, & Lac, 2015).
INTERNAL
________ validity is the extent of generalizability or certainty that results can be applied to other respondent groups, different settings, and different ways of operationalizing the conceptual variables.
EXTERNAL
________ validity is the extent to which the operationalization of a variable represents a reliable and valid representation of the theoretical construct it is meant to represent.
CONSTRUCT
_________ is the extent to which the results are valid given the statistical results presented.
STATISTICAL CONCLUSION VALIDITY
What makes for a good research hypothesis?
A good research hypothesis is clearly rooted in prior research and capable of being tested.
What is meant by the term "confound"? What are some important confounds to consider when designing experimental research?
A confound presents an alternative explanation for research findings. Common confounds include selection effects, design confounds, expectancy effects, demand characteristics, placebo effects, instrumentation, and order effects. In quasi-experimental designs, they might also include history, maturation, attrition, etc.
What is the most common way that psychologists seek to achieve external validity?
Through replication.
What is the difference between a between-subjects variable and a within-subjects variable?
With a between-subjects variable each participant receives only one level of that independent variable. With a within-subjects variable each participant receives each level of the independent variable.
What is meant by the term "p-hacking"?
P-hacking occurs when a researcher engages in questionable research practices in order to increase the likelihood of finding a significant result.