INTRODUCTION TO SCIENTIFIC METHODBISC 230 Lab IIFebruary 6th 2015

WHAT IS SCIENCE? • Body of information or knowledge about nature.

• Process of getting information.

• Best method to acquire knowledge if the goal is observe the nature Others: From communication Faith, dogma such as religion.

ADVANTAGES AND LIMITATIONS ADV• Information is updated and revised constantly• Free from bias, prejudice and distortion.

LIM• Not testing not science • Inside the physical universe

SCIENTIFIC METHOD1. Curiosity ? Observations Generalizations what is wrong? Fertilizers will make any plant grow2. Working hypothesis: Parameters must be control and measured Testable statement (non-testable statement?)3. Testable prediction: General Specific

if _________, then ________________(specific result, data)4. Experiment: Creativity, understanding, practical. Control variables

Deductive reasoning

DEDUCTIVE VS INDUCTIVE • Deductive reasoning or deduction:

General statement, or hypothesis, and examines the possibilities to reach a specific, logical conclusion.

• if something is true of a class of things in general, it is also true for all members of that class. For example, "All men are mortal. Harold is a man. Therefore, Harold is mortal."

• Inductive reasoning: Broad generalizations from specific observations. Even if all of the premises are true in a statement, inductive reasoning allows for the conclusion to be false. Here’s an example: "Harold is a grandfather. Harold is bald. Therefore, all grandfathers are bald." The conclusion does not follow logically from the statements.

Scientists use induction to form hypotheses and theories. Deductive reasoning allows them to apply the theories to specific situations.

VARIABLESA) Dependent: expected to change

B) Independent : manipulated, you change them. ONLY 1 at time. more observe correlation.

C) Control: Factor that affect the results, keep constant.

BACKGROUND INFO/RESULTSBACKGROUND 1. Previously published literature Limits, ranges, correlations.

2. Pilot studies Replications

RESULTSStatistical analysis: is the prediction verified or not?a) Supported but never true (one part of the hypothesis under specific conditions)b) Rejected: disproven

THEN WHAT? • Do it again!!! Inductive reasoningReviseRestate disproven New hypothesis/ supported modify more specificNew predictions and experiments

Working hypothesis is a living idea that changes as evidence accumulatesHypothesis “BEST IDEA AT THE MOMENT”HYPOTHESIS THERORY : Many scientist with same conclusion (extensive experimentation under wide range of conditions)

LETS DO IT!!!!!!!• RESEARCH PROJECT: Think Design Execute Analyze • GOAL Characterized people at USC General statement: inductive reasoning, -/+ correlations. 1. 5 groups of 4 GS 2. As a group choose one GS 3. Predictions from the best GS 4. Design the experiment: Materials, methods (10 groups of 2) 5. Gather and compare results: send them to vazquezr@usc.edu 6. Modify hypothesis and discuss further experiments in the report: 1 page report address questions in II-4