Scientific Experimental Design Terms

Systematic errors

• Errors that are involve consistent shifts in measurements in the same direction and by the same amount.

• Affects accuracy

• Causes: uncalibrated or faulty equipment and environmental factors.

• To improve: calibrate all measuring equipments before use.

Random errors

• Errors that fluctuate unpredictably and not consistent in direction or magnitude.

• Affects reliability, precision, accuracy

• Causes: measurement limitations and environmental variations.

• To improve: take multiple measurements and calculate averages.

Systematic errors

• Errors that are involve consistent shifts in measurements in the same direction and by the same amount.

• Affects accuracy

• Causes: uncalibrated or faulty equipment and environmental factors.

• To improve: calibrate all measuring equipments before use.

Random errors

• Errors that fluctuate unpredictably and not consistent in direction or magnitude.

• Affects reliability, precision, accuracy

• Causes: measurement limitations and environmental variations.

• To improve: take multiple measurements and calculate averages.

Validity

• Only having 1 independent variable present.

• Ensures that the results obtained are due to changes in the independent variable only, and not by other factors.

• To improve validity: include control variables and control group.

Accuracy

• How close the results are is to the true value.

• Ensures results are reliable.

• To improve: calibrate equipment

Precision

• How close the values are to each other.

• Ensures results are reliable.

• To improve: conduct multiple trials and take the average between numerous trials.

Reproducibility

• The ability for the same experiment can be repeated under same conditions by different groups.

• Ensures results are reliable

• To improve: provide detailed methodology.

Repeatability

• The ability for same experiment to be repeated under the same conditions by the same group.

• Ensures consistency in results and reliable data.

• To improve: accurate measurements and consistent lab conditions.

Improvements of the methodology

Modifying the procedure or equipment to improve VAPRR of the experiment.

Extension of experiment

The process of expanding the scope or duration of an experiment to explore additional variables, conditions, or effects.

anomalies

irregular result obtained (e.g. too low or too high) or any data that do not fit in with general trend.