The Scientific Method

The Scientific Method

1. The steps of the scientific method

   • 1. Observation
     • An observation is when something is noticed
   • 2. Hypothesis
     • An educated guess based on an observation
   • 3. Experimentation
     • An experiment is designed to test a hypothesis
   • 4. Collection and interpretation of data
     • Data consists of measurements, observations or info gathered from experiments
   • 5. Conclusion
     • A summary of the results of an experiment
   • 6. Relating the conclusion to existing knowledge
     • Supported if results agree fully
     • Changed if results agree only partly
     • Rejected if results contradict
   • 7.Reporting and publishing the results
     • Scientific journals, magazines, world wide web

2. Theories and principles

   • A theory is a hypothesis that has been supported by many different experiments
   • A principle or law arises from a theory that has been shown to be valid when fully tested over a long period of time

3. Principles of experimentation

   • 1. Careful planning and design
     • Only a single variable should be tested
   • 2. Ensure that the experiment is safe
     • E.g- tie long hair back, wear a lab coat
   • 3. Design a control experiment
     • A control is used to provide a comparison against which the actual experiment can be judged
       • Placebo pill
   • 4. Experiments must be fair
     • Sample size as large as possible, random selection, replications must be possible, double blind testing

4. Limitations of the value of the scientific method

   • The extent of our knowledge
     • A basic amount of knowledge is required
   • The basis of investigation
     • A badly designed experiment will lead to poor results
   • Interpreting results