Unit 3-Experimentation Flashcards
What is a pilot study?
Short experiment that are commonly carried out before starting a scientific investigation
What is the purpose of a pilot study?
To develop and improve experimental protocols, ensuring the experimental design is suitable for investigation the aim
Give advantages of pilot studies
- Allows a new protocol to be developed
- Ensures an appropriate range of values for the independent variable
- Allows practice of an established protocol
What are the three type of variables?
Independent, Dependent, Confounding
What is an independent variable?
Variable that is deliberately manipulated by the investigator to determine if it has an effect on the outcome of the experiment
What is a dependent variable?
Variable that is measured to determine if changing the independent variable has an effect
What is a confounding variable?
Variable, other than the independent variable that may affect the dependent variable
What is used if confounding variables cannot be controlled effectively?
Randomised Block Design
What type of sampling is Randomised Block Design?
Stratified Sampling
What are the two classes of variables?
Discrete
Continuous
What are discrete variables?
Finite values that allow placement into groups
Give an example of a discrete characteristic
Sex
What are continuous variables?
Values that change gradually from one extreme to another
Give examples of qualitative data
Colour of leaf
Emotions
How is qualitative data presented?
Bar graph