THE PROCESS OF SCIENCE
Assumptions
Nature is real, understandable, knowable
through observation
Nature is orderly and uniform
Measurements yield knowledge of the thing
measured
Natural laws are not affected by time
Fact
A thing that has actually happened or is true
The state of things as they are; reality; truth
Observation
The act, practice, or power of observing, or
noticing
A noting and recording of facts and events
The data so noted and recorded
Phenomenon (observable event)
Any fact or event that is apparent to the senses
and can be scientifically described
The appearance of something experienced as
distinguished from the thing itself
Hypothesis
Inductive Reasoning: Reasoning from
particular facts to a general conclusion.
Hypothesis: An unproved theory,
proposition, etc. tentatively accepted to
explain certain facts or to provide a basis
for further investigation, argument, study,
etc.
Prediction – The Basis for
Directed Observations and
Experiments
Deductive reasoning: The process of
reasoning in which a conclusion follows
necessarily from the stated premises;
inference by reasoning from the general to
the specific.
IF; THEN: predicting things that would happen
if a hypothesis is correct.
Experiments
Variables: things that can vary or change
Control of variables: constant or uniform
Experimental variable: what you are experimenting with
Control group: reference point
Objective data: clear with no overlap
Dependent and independent variables
Growth of Pea Plants as Affected by Atmospheric
Carbon Dioxide Concentration
Effect of Growth Hormone on Juvenile Muskrats
Treated
Fortified
Weight (gms)
(Dependent Variable)
Height of Plant (cm)
(Dependent Variable)
Ambient
20
15
10
5
0
0
20
40
60
80
800
700
600
500
400
300
200
100
0
100
0
5
10
Days (Independent Variable)
2
3
4
5
6
7
15
20
25
30
Days (Independent Variable)
pH over Time, Mud Pond Transect 1
1
Control
Mud Pond Transect 1
Average Deviation from mean pH Over Time
(± .05 confidence interval)
8
8.0
All Points
Fen Only
0.6
Average Deviation from Mean pH
7.5
pH
7.0
6.5
6.0
0.4
0.2
0.0
-0.2
-0.4
Date
11/11/1998
10/28/1998
10/14/1998
9/30/1998
9/16/1998
9/2/1998
8/19/1998
8/5/1998
7/22/1998
7/8/1998
6/24/1998
6/10/1998
5/27/1998
5/13/1998
4/29/1998
11/11/1998
10/28/1998
10/14/1998
9/30/1998
9/16/1998
9/2/1998
8/19/1998
8/5/1998
7/8/1998
6/24/1998
6/10/1998
5/27/1998
5/13/1998
4/29/1998
4/15/1998
7/22/1998
Date
4/15/1998
-0.6
5.5
10/18/1999
10/4/1999
9/20/1999
9/6/1999
8/23/1999
8/9/1999
7/26/1999
7/12/1999
y = -3E-09x + 0.0004x - 19.879x + 481940x - 4E+09
2
R = 0.5412
3
6/28/1999
4
6/14/1999
11/11/1998
10/28/1998
10/14/1998
0.2
5/31/1999
5/17/1999
5/3/1999
4/19/1999
4/5/1999
Average deviation from seasonal mean pH
9/30/1998
9/16/1998
9/2/1998
8/19/1998
8/5/1998
7/22/1998
7/8/1998
6/24/1998
6/10/1998
5/27/1998
-0.4
5/13/1998
4/29/1998
4/15/1998
Average Deviation from Mean pH
Mud Pond Transect 1
Average Deviation from mean pH Over Time
(± .05 confidence interval)
0.6
0.4
Replication
0.0
-0.2
y = 5E-05x - 3.2783x + 59053
2
R = 0.8162
2
-0.6
Mud Pond Transect 1
Average Deviation from Mean pH Over Time
(± .05 confidence interval)
0.6
0.4
0.2
0.0
-0.2
-0.4
2
-0.6
Theories
A formulation of apparent relationships or
underlying principles of certain observed
phenomena which has been verified to some
degree.
With sufficient verification, a Theory may
come to be referred to as a Principle or a
Law
Scientific Method: a
Flashlight example