scientific method: hypothetic-deductive method with seven steps

scientific method: hypothetic-deductive method with seven steps

1. Step 1: observation

2. step 2: gather information

3. step 4: prediction

4. step 5: experiment

5. step 3: hypotheses

   • a hypothesis is a tentative statement about nature, the purpose of which an experiment is done
   • null hypothesis is set up to be refuted by the experiment

6. step 6: conclusion

   • descriptive statements that best explain resluts

7. step 7: communication of results

8. observation vs. manipulative

   • observational experiment: take advantage of natural perturbations or natural differences
   • manipulative experiment: more power, more control, more costly(trade off)

9. experimental design issues in aquatic biology

   • 1. psudoreplication
   • 2. limited reference sites
   • 3. lack of "before" data
   • 4. logistics

10. elements of a good experiment

    • control: any treatment against which one or more other treatments can be compared
    • replication: (sample size important) having more than one experimental unit per treatment
    • randomization: the process of randomly allocating treatments and controls to experimental units OR randomly selecting samples from a population