Scientific Methods Section 2.1 Objectives: List and describe the steps of the experimental method. Describe how scientists study subjects in which experiments are not possible.
Experimental Method (aka, “Scientific Method”) Observation Question Hypothesis Experiment Only allow one variable to change Use a control group for comparison Repeat the experiment Organize and analyze data Communicate results
Correlation Method What scientists use when they cannot answer a question experimentally. What was Earth’s climate like 60 million years ago? Does smoking cause lung cancer? Correlation – reliable associations between two or more events Tree rings Lost Colony (Roanoke Island, VA) Jamestown, VA
Rainfall and Tree Ring Width Chapter 2 Section 1 Scientific Methods Rainfall and Tree Ring Width
Good Scientists Are: Curious Skeptical Open to new ideas Intellectually honest Imaginative and creative (John Snow’s spot map)
John Snow’s Cholera Spot Map Chapter 2 Section 1 Scientific Methods John Snow’s Cholera Spot Map
Quick Quiz Why should the results of an experiment be repeatable? Why are experiments designed to have as few variables – preferably only one – as possible? Why is the correlation method a useful accompaniment to the experimental method?