Scientific method

Independent variable

Variable changed by the scientist during an experiment

Dependent variable

Variable that responds to or changes as a result of manipulating the independent variable

Control variable

Factors that are kept constant during an experiment to ensure a fair test

Placebo

A fake treatment used with a control group in medical trials

Double blind testing

Neither researcher or test subject know who is receiving the test drug

Quantitative Data

Numerical measurements and observations

Qualitative Data

Non-numerical descriptive observations

Repeatability

Ability to obtain consistent results when an experiment is conducted under identical conditions

Validity

The extent to which an experiment actually measures what it claims to measure

Error

Refers to the difference between a measurement and it’s true value

Uncertainty

To the range of possible values within which the true value of the measurement lies

Statistical uncertainty

A measure of the range of random variation in the results obtained when repeated measurements of the same event are recorded

Systematic uncertainty

Arises from defects in the measurements apparatus, equipment or method used by the experimenter

Correlation

A statistical relationship between two variables

Causation

A direct cause-and-effect relationship between variables

Control group

A group in an experiment that does not receive the experimental treatment

Experimental group

A group that receives the specific treatment being tested

Accuracy

How close a measurement is to the true value

Precision

How close multiple measurements of the same thing are to each other