OCR Biology PAG Key Terms

dependent variable

The measurable effect, outcome, or response in which the research is interested.

independent variable

The experimental factor that is changed; the variable whose effect is being studied.

control variable

A variable that is kept constant during a controlled experiment.

percision

size of the smallest unit you're measuring to - the smaller the more precise - doesnt increase upon accuracy

valid/validity

how certain can you be that you're independent variable is affecting you're dependent variable

accurate/accuracy

how free from error are you, closeness to true value = most accurate

significance

have you/can you perform a statistical test (only use in relation to statistical test.

random error

Error that is due to chance and is not standardized. Decreases precision.

systematic error

error resulting from some imperfect aspect of the research design that causes respondent error or from a mistake in the execution of the research

calibration

setting to a fixed value (eg. colorimeter, microscope, ruler and scale.)

anomaly

deviation from what is normal - not fitting trend

confidence

how significant a statistical test is

control

a condition you run to ensure validity with no independent variable ruling out potential inhibiting factors to act as a comparison

repeatable

the experiment can be produced by another person and the same results can be achieved

reliable

consistently good in quality or performance; able to be trusted.