week one Flashcards
(45 cards)
Hypothesis
Stated as effect of independent variable on the dependent varible
Primary hypothesis
Test hypothesis for which an experiment is powered
Secondary hypothesis
Often times other effects of an IV of an IV are examined
But the effects is not necessary powered to state an effect statistically
Null hypothesis
Statistical concept which state there is not effect of IV on the DV
One sided hypothesis
You assume the DV will move in one direction
Two sided hypothesis
You do not know if DV will go up or down
Structural of hypothesis
-form the basis of all questions
-should be reflected in title of manuscript
-abstract
-posters
Grant application
They are the basis of Specific Aims in grant
IV
What the investigator control/manipulate to produce a change of DV
Should be only one depended factor
Does, choice,
DV
what the IV affects, what you measure
Frequency
Change HR
Ml of urine
Confounding variable
Unknown factors that disrupt or influence the effect of the IV on the DV
Random error
Inherent aspect of measurement which increase variability and reduces the ability to detect differences among the group
Why random person error is very. Difficult to control
As it an inherent aspect of measurements and pure and unknown
Confounding variable is control by
Randomized blocking with reduces the influence of confounding
But it will increasing variablity
Aim of experimental design is to
Isolate the effect of the IV on the DV
Type of control
Positive control Negative control Vehicle control Sham control Procedural control repeated measure
Positive control
Group added to a design where you know what the outcome will be and the outcome is expected to move in the direction of think the independent variable should move it
Positive CONROL used
To ensure that the experimental set up is working
By moving the experimental and positive control in the anticipated direction
So the design is more valid by IV is actually affecting the DV
- provide a comfort about the effects of the independent variable
- tell you the system is set up correctly and working enhancing your confidence in the negative results are truly negative
When. We can used positive. Control
Whenever you possible
Negative control
Is a group added to a design where you know the outcome, but unlike the positive control you known that the IV will not affect the group
Benefit of the negative control
Helps guard against epiphenomenon , it tells you that is something else influencing the
Do
Epiphenomenon
A result that accompanies another, but has no causal influence itself or was not caused by experimental paradigm
Vehicle control
This has everything you are administering except the level of the IV
Sham control
Associated with a surgical intervention where a mock surgery is performed , A form of a procedural control
Procedural control
Running the same procedure without the active intervention
