Glossary Vocabulary Flashcards
All vocabulary in the glossary is game on exams!
Primary hypothesis
The tested hypothesis for which an experiment is powered. It is the effect of the independent variable on the dependent variable.
Secondary hypotheses
(there could be several); Oftentimes other effects of an I are examined, but the hypothesis is not necessarily powered to state an effect statistically.
One-sided hypothesis or one-tailed test
you assume the DV will move in one direction.
Two-sided hypothesis or two-tailed test
You don’t know if DV will go up or down
Null hypothesis (Ho)
A statistical concept which states there is no effect of the IV on the DV, it is often credited as the primary test and if structured properly ensures no pre-conceived bias and fulfills the notion of randomness
Independent Variable (IV)
what the investigator controls/manipulates to produce a change in the DV
Dependent Variable (DV)
What the IV effects; i.e. what you measure
Confounding Variables
Known factors that disrupt or influence the effect of the IV on the DV that should be recognized prior to the initiation of an experiment
random error
is an inherent aspect of measurement which increases variability and reduces the ability to detect differences among groups.
Positive Control
is a group added to a design where you know what the outcome will be and the outcome is expected to move in the direction you think the independent variable should move it.
Negative Control
is a group added to a design where you know the outcome, but unlike the positive control, you know what the IV will not affect the group
epiphenomenon
a result that accompanies another, but has no causal influence itself or was not caused by the experimental paradigm
Vehicle control
(injectate or pill without the test substance). This has everything you are administering except the level of the IV.
Sham control
(generally associated with a surgical intervention where a mock surgery is performed). A form of procedural control
Procedural control
(running the same procedure without the active intervention). This generalized control procedure would include sham controls, which is a special case of procedural control but is outside of the realm of surgery.
Repeated measures
will use the subject as its own control of alternatively in a non-repeated measures design, using one side of the animal as a control for the other.
Hypothesis Driven Research
in which a specific hypothesis is laid out upfront and then tested prospectively.
Prospective studies
a study where a hypothesis is formulated and then tested after the design has been laid out
Retrospective studies
that assess the effect of an IV on a DV after the fact; after the IV effect on the DV has occurred. These are commonly used in clinical studies
discovery research
formulates the basis for hypothesis driven research. It generally involves mining data sets or output to determine if a relationship will emerge so that a hypothesis can be formulated
clinical trial
a study on patients that is always prospective and tests a very specific hypothesis generally about a drug or specific type of intervention. it is the most rigorous (from a control perspective) type of clinical research.