Steps in the Scientific Method:

1. Observation- 
                Scientists need to be curious about the world around them. After wondering
                about  a phenomenon, a scientist would formulate a testable question or problem to help
                explain  this phenomenon.
                 [Example of a question/problem: Does increasing temperatures increase the rate of perspiration
                 in mice?]

2. Hypothesis-
            A hypothesis is a possible answer or solution to the question.  It is an
                  educated guess that makes a prediction.  It is often stated as "If...Then..." 
                  For further clarification, go here.
                  [Examples:
                       1. Temperature has a direct effect on the rate of production of perspiration.   OR.........
                       2. If increasing temperatures increase the rate of perspiration, then mice exposed to
                           increasing temperatures, should produce more perspiration.]...........OR.........
                      3. If the temperature is increased, then mice will produce more perspiration.]

3. Experimentation -
                   An experiment is scientific testing. Experiments are designed to test hypotheses.
                   There are certain components of all experiments:
                             
                              a. Variables- These are the factors that are being tested in the experiment. Ideally, there
                                  should be only one independent variable (so that any differences observed in the
                                  experimental group can be attributed to this particular variable).
                                                     Independent variable- the variable that is manipulated by the experimenter.
                                                     Dependent variable- the variable that is dependent on the independent variable.
                                                                                        This is what the experimenter is measuring.
                                                     Managed variables- these are the variables (conditions) that are managed by the
                                                                                       experimenter so that they are the same for both the
                                                                                       experimental group and the control group. (They are
                                                                                       sometimes called "controlled variables", which should not
                                                                                       be confused with "the control group".)
                                                    [Example: the independent variable would be the temperature, and the dependent
                                                    variable would be the amount of perspiration produced by a mouse.  All other
                                                    factors, such as size of mouse, humidity, environment, food and water provided, etc.
                                                   would be managed variables.]

                               b. Control-    The control is used to compare with the experimental group to see if there are any
                                                     differences. The control is set up exactly the same as the experimental group,
                                                     except for one thing-- the independent variable.

                               c. Experimental group-  This is the group of specimens which are being tested.

                                     [Example: Twenty similar sized mice of the same species, are divided into two groups.
                                     Group 1: Ten of the mice are put in the test chamber at 20 degrees C for 1 hour, and the
                                     amount of perspiration for each mouse during this period is measured.  Group 2: Ten of
                                     the mice are put in the test chamber at 20 degrees C for 10 minutes, and the temperature
                                     is increased 1degree C every ten minutes, for a total of 60 minutes.  The amount of
                                     perspiration for each mouse during this period is measured.  Group 1 is the Control group,
                                     whereas, Group 2 is the experimental group.]

                               d. Data-        These are observations or numerical facts gathered during  the experiment.
                                     [Example: The amount of perspiration for each mouse would be the data in this experiment.]

4. Conclusion-
                    After performing the experiment, the scientist must either accept
                    his hypothesis  as true, or reject the hypothesis as false.  (The hypothesis is either
                    supported or not supported.  Hypotheses can never be proven, only disproven.)

5. Confirmation-
                  The scientist must confirm his results by repeating his experiment.  This is to be sure
                   his results have not been affected by experimental error.
                  Scientists usually submit their work to publications, so that other
                  scientists also have the opportunity to confirm or refute the results. 
                  Scientific publications solicit peer reviews BEFORE printing the research findings.  This is
                  what makes the scientific process so powerful----other scientists, who specialize in the area,
                  question, retest, or analyze the results, before the research is accepted and published.

5. Theory-
                   A hypothesis which has been accepted as true, which has been tested
                   many times and which has never been proven false after many years,
                   may become a theory.  A theory is not usually an isolated bit of
                   information, but, on the contrary, it is usually combined with other
                   related hypotheses to form a general frame-work which  explains
                   certain phenomenon.  A theory is a "big deal" in science.

6. Scientific Law-
                      A scientific law is an indisputable truth.
                      It is an established principle of science.
 
 
 

©1998 Linda Pellegrini. All rights reserved.