THE SCIENTIFIC METHOD & EXPERIMENT DESIGN Unit: _Exp. Design____ THE SCIENTIFIC METHOD & EXPERIMENT DESIGN What are some key elements of sci. method that come to mind? 1

The process by which we study the world around us. The Scientific Method The process by which we study the world around us. “organized common sense” 2

Consists of several parts: The Scientific Method Consists of several parts: -Observe -Hypothesize -Experiment -Conclude 3

Used to identify a problem. Observe Used to identify a problem. 4

educated prediction about relationship between variables Hypothesis educated prediction about relationship between variables testable explanation of observations “If… then…” statement 5

method used to test hypothesis Experiment method used to test hypothesis must be controlled (as best as possible) collect qualitative or quantitative data 6

Answer the problem or ask a new question. Conclude Answer the problem or ask a new question. Develop a theory (if enough experimentation has been completed) 7

Different types of Theories Theory Different types of Theories - Scientific - Common Theory 8

Scientific Theory vs. Common Theory -Supported by evidence Examples: -Atomic Theory -Evolution Common Theory -Based on hunches and guesses. -aka “Hypothesis” 9

THE SCIENTIFIC METHOD & EXPERIMENT DESIGN Unit: _Exp. Design____ THE SCIENTIFIC METHOD & EXPERIMENT DESIGN What are some key elements of sci. method that come to mind? 1010

Warm-Up 7/29/2014 Which of the following steps in the scientific method was represented by the “Easter Bunny”?

Parts of a VALID experiment - Question - Hypothesis - Independent Variable - Dependent Variable - Control - Constants - Repeated Trials 12

Vocabulary Terms Variable Factors that change in an experiment. 13

Vocabulary Terms Independent Variable Dependent Variable - The variable that the experimenter purposefully changes/manipulates. Dependent Variable - The variable that changes as a result of the Independent Variable. (DV gets measured.) 14

Control Constant Vocabulary Terms -The normal situation (Ind. Var.) left unchanged. Used to compare effects of the IV when changed. Constant -Every other factor in the exp. that is not a variable. 15

Repeated Trials Vocabulary Terms -The number of times the experiment is repeated. -The more the better. 16

Problem: The effect of the IV on the DV. Experimental Design Problem: The effect of the IV on the DV. -The effect of medicine dosage on blood pressure. Hypothesis: If…then…statement. -If medicine dosage is related to blood pressure and medicine dosage is changed, then blood pressure will change. 17

Experimental Design IV= -dosage. DV= -blood pressure. 18

Control: Constants: Experimental Design -placebo, no medicine given. -type of medicine -gender, age -diet -what else? 19

Done after the experiment is complete: Experimental Design Done after the experiment is complete: -Analyze/Infer- What did the data show? What was learned? What other questions came about? 20