Scientific Method and Theory Dr. James Danoff-Burg Columbia University

Goals of science  Describe the patterns that are found in the natural world  Explain patterns This is the major emphasis of your individual projectThis is the major emphasis of your individual project Ditto for most of the activities that we are doing in the classDitto for most of the activities that we are doing in the class  Scientific method is applicable to many other aspects of life

Methods of Explanation  Approximately 11 Steps  Process is repeated many times  Can NEVER prove a hypothesis Can only reject many, leaving one as best supported by the dataCan only reject many, leaving one as best supported by the data “Scientific Proof” is a common fallacy“Scientific Proof” is a common fallacy

Hypotheses  Null hypothesis The hypothesis of no changeThe hypothesis of no change Often abbreviated as H oOften abbreviated as H o  Alternative hypotheses Often abbreviated as H a, H b, etc.Often abbreviated as H a, H b, etc. All must be mutually exclusiveAll must be mutually exclusive We accept one if H o is statistically rejectedWe accept one if H o is statistically rejected –Which H a to accept is determined by trends in data

Scientific Method - Steps 1-5  Observe or suspect pattern  Posit significance of observed difference  Create question to explain pattern  Create testable hypotheses  Design experiment

 Collect data (Descriptive stage)  Analyze data, primarily using statistics  Evaluate hypotheses, reject H o ?  Make conclusions based on data  Note problems in current work  Predict future directions for research Scientific Method - Steps 6-11

Parts of a scientific report  Title  Abstract - an overall summary  Introduction - background, question, H a s  Methods - what we did  Results - what we found, graphs, summarized data  Discussion - interpretations, predictions  Acknowledgements - who helped us  References - who we cited

Scientific Communication  Written report TraditionalTraditional  Oral presentation Commonly used for preliminary presentation of work to get feedback before writing it upCommonly used for preliminary presentation of work to get feedback before writing it up  Poster Visual summary of work - used at conferencesVisual summary of work - used at conferences  Web page Can use a written report & make it interactiveCan use a written report & make it interactive

Individual Projects – Seven Parts to Design  Question  Null hypothesis & Alternative hypotheses  Independent variable(s)  Dependent variables  Desired data to collect  Data collection method  Expected outcome with reasons as to why you expect that