Investigative and Practical Skills

Limitations, Accuracy & Reliability

Limitations, Accuracy & Reliability

Limitations

accuracy   Experimental limitations are factors that are out of your control. They include:

  • time
  • materials
  • apparatus
  • techniques
  • money

Limitations can have an effect on the reliability and precision of your experiment, however, and need to be taken into consideration when reaching any conclusions.

Although you can’t help them, there are still ways in which limitations can be reduced. For example by:

  • calculating in any apparatus errors
  • conducting a good number of experimental repeats
  • keeping other variables as constant as possible
  • ensure all equipment used is clean (using distilled water) and dry

Obviously, the limitations and how to reduce them where possible will depend entirely on the experiment being conducted

Accuracy and Reliability

You need to take into consideration the accuracy and reliability of your results.

  • Accuracy refers to keeping all measurements as accurate as possible. The quality of your results depends on how accurately you measure particular solutions or take down your data. Accurate data are measurements that are close to the true value.
  • Reliability refers to the variation between valves. In order for your data to be reliable this variation must be as small as possible. If your findings are reliable then they can be repeated, for example by other scientists or by other techniques.

In order to improve reliability you should be as specific as you can with your variables. All other conditions in which you conduct your experiment must be kept constant. If they’re not then another variable will have been changed and your results will no longer be valid.