Scientific MethodScientific Method

Steps to Solving a Steps to Solving a ProblemProblem

(The Scientific Method)(The Scientific Method)1.1. Identify the Problem-”Question” or “Problem”Identify the Problem-”Question” or “Problem”

• State the problem to be solved or the question to be answered.State the problem to be solved or the question to be answered.

2.2. Collect Information/Research – “Data”Collect Information/Research – “Data”• Obtain facts and ideas from books, journals, internet, etc. that provide Obtain facts and ideas from books, journals, internet, etc. that provide

insight regarding your problem/question. Cite these resources.insight regarding your problem/question. Cite these resources.

3.3. Form an opinion – “Hypothesis”Form an opinion – “Hypothesis”• Based on the information/research you collect, propose a solution or Based on the information/research you collect, propose a solution or

“best guess” that will help guide your experimentation and attempt to “best guess” that will help guide your experimentation and attempt to answer the proposed problem/question.answer the proposed problem/question.

4.4. Test Your Hypothesis – “Test Your Hypothesis – “Experiment”Experiment”• Describe, design, and conduct an experiment that will give you Describe, design, and conduct an experiment that will give you

information or data that supports (or not) your hypothesis.information or data that supports (or not) your hypothesis.

5.5. Accept or Reject Your Hypothesis – “Accept or Reject Your Hypothesis – “Analysis”Analysis”• Determine whether your data/results from the experiment supports (or Determine whether your data/results from the experiment supports (or

not) your hypothesis; if not, it may be necessary to review your not) your hypothesis; if not, it may be necessary to review your information/research and revise your hypothesis.information/research and revise your hypothesis.

6.6. Report Your Results – “Report Your Results – “Conclusion”Conclusion”1.1. Formulate a conclusion that answers the original question from step one Formulate a conclusion that answers the original question from step one

and share the results with the scientific community (or the community at and share the results with the scientific community (or the community at large).large).

ObservationsObservations datadata that are descriptions of qualities that are descriptions of qualities such as shape, color, taste, feel, etc…such as shape, color, taste, feel, etc…

acquired by using your sensesacquired by using your senses

two types:two types:1.1. Objective observation Objective observation

2.2. Subjective observationSubjective observation

2 Types of 2 Types of ObservationsObservations

ObjectiveObjective

an an observationobservation based based on on factfact

**factfact – a piece of – a piece of information that information that can be strictly can be strictly defined and defined and proved true.proved true.

SubjectiveSubjective

an an observationobservation based on based on opinionopinion

**opinionopinion – a statement – a statement that expresses a that expresses a belief, value, or belief, value, or feelingfeeling

Objective or Subjective?Objective or Subjective?Science looks like fun today!Science looks like fun today!

SubjectiveSubjective

Kanye West’s songs sound good!Kanye West’s songs sound good!

SubjectiveSubjective

The table tops in class are white!The table tops in class are white!

ObjectiveObjective

Chow hall French fries taste good!Chow hall French fries taste good!

SubjectiveSubjective

The summer is too short!The summer is too short!

SubjectiveSubjective

There are sixty seconds in a minute!There are sixty seconds in a minute!

ObjectiveObjective

Objective or Objective or Subjective?Subjective?

Which type of Which type of observationsobservations should be used should be used in science?in science?

ObjectiveObjective observationsobservations should should be used in science because be used in science because they are based on facts and they are based on facts and the basis of science is to the basis of science is to identify the facts!identify the facts!

InferenceInferencean explanation that tries to make sense of your an explanation that tries to make sense of your observationsobservations

influenced by your experiences/prior knowledgeinfluenced by your experiences/prior knowledge

these explanations may not be truethese explanations may not be true

ExampleExample

ObservationObservation::

John was breathing heavily as he walked into the classroom.John was breathing heavily as he walked into the classroom.

Possible Possible InferencesInferences::

He ran to class because he was going to be lateHe ran to class because he was going to be late

He just played basketball in gymHe just played basketball in gym

AKA: An Educated

guess

What would you What would you infer?infer?

1.1. Everyone is closing their book because…Everyone is closing their book because…

2.2. Many students buy French fries Many students buy French fries because…because…

3.3. Students arrived to class sweaty Students arrived to class sweaty because…because…

4. All of the students are laughing 4. All of the students are laughing because…because…

HypothesisHypothesisa working explanation or trial answer to a problem a working explanation or trial answer to a problem

an an “educated guess”“educated guess”

can be written in the form of an can be written in the form of an “If..., then..., “If..., then..., because...” because...” statementstatement

is not necessarily proven correct just because is not necessarily proven correct just because data/resultsdata/results from one from one experimentexperiment supports it supports it

when repeatedly supported by the same results when repeatedly supported by the same results theories theories laws laws

ExampleExample

IfIf an individual increases his/her activity level, an individual increases his/her activity level, thenthen their heart their heart rate will increase rate will increase becausebecause the body’s muscles (cells) will the body’s muscles (cells) will

require more oxygen to function at a higher level. A faster require more oxygen to function at a higher level. A faster beating heart will increase blood flow; thus, allowing an beating heart will increase blood flow; thus, allowing an

increased concentration of oxygen to reach the cells in need.increased concentration of oxygen to reach the cells in need.

DataDatafactual informationfactual information

two typestwo types 1. Quantitative1. Quantitative

2. Qualitative2. Qualitative

2 Types of Data2 Types of DataQuantitativeQuantitative

datadata consisting of consisting of numbersnumbers

ExampleExample

Heart rate (80 Heart rate (80 beats/minute)beats/minute)

QualitativeQualitative

datadata consisting of consisting of verbal descriptions or verbal descriptions or information gathered information gathered using scales without using scales without numbersnumbers

ExamplesExamples

Verbal description of Verbal description of heart rate (fast or heart rate (fast or

slow)slow)

Repeated TrialsRepeated Trialsexperimental experimental tests done more than oncetests done more than once

necessary to provide more accurate necessary to provide more accurate results; results; datadata is averaged together is averaged together

lessens the impact of a chance error on lessens the impact of a chance error on the experimental resultsthe experimental results

ExamplesExamples

In the heart rates lab each participant recorded their heart In the heart rates lab each participant recorded their heart rates after performing various activities. Each rates after performing various activities. Each

participant’s data (for resting, walking, and running) participant’s data (for resting, walking, and running) represents a trial. If five total individuals performed the represents a trial. If five total individuals performed the activities and gathered data, then there were a total of activities and gathered data, then there were a total of

five trials. five trials.

VariablesVariablesthings that can be assigned or take on things that can be assigned or take on different values in an different values in an experimentexperiment

any factor that can changeany factor that can change

two typestwo types 1. Independent1. Independent

2. Dependent2. Dependent

Two Types of Two Types of VariablesVariables

IndependentIndependent

variablesvariables that are that are purposely changed or purposely changed or manipulated in an manipulated in an experiment experiment

the factor that you wish the factor that you wish to testto test

usually expressed after usually expressed after the word “if” in the the word “if” in the hypothesishypothesis

could be thought of as could be thought of as the “cause” in a cause the “cause” in a cause and effect relationshipand effect relationship

ExampleExample

The activity level (resting, The activity level (resting, walking, running) walking, running)

DependentDependent

variablesvariables that may change as a that may change as a result of the independent result of the independent variablevariable

the factor you measure to the factor you measure to gather resultsgather results

usually expressed after the usually expressed after the word “then” in the word “then” in the hypothesishypothesis

could be thought of as the could be thought of as the “effect” in a cause and effect “effect” in a cause and effect relationshiprelationship

ExampleExample

The person’s heart rateThe person’s heart rate

Identify the Identify the VariablesVariables

1. Students receive $1.00 for every

correct answer on the test.

Independent Variable

Dependent Variable

Control or Control Control or Control GroupGroup

a group of subjects in an a group of subjects in an experimentexperiment that are that are not given any special treatmentnot given any special treatment

something that is not manipulatedsomething that is not manipulated

same as the same as the experimental group experimental group in every in every possible way, except for the factor being tested possible way, except for the factor being tested

a neutral point of reference for comparison – it a neutral point of reference for comparison – it allows you to see what changing a allows you to see what changing a variablevariable does does by comparing it to not changing anything.by comparing it to not changing anything.

ExampleExample

The resting heart rate represented the baseline heart rate to The resting heart rate represented the baseline heart rate to which any increase in activity level was compared to.which any increase in activity level was compared to.

ConstantsConstantsFactors in an experiment (both in the Factors in an experiment (both in the experimentalexperimental and and control groupscontrol groups) that are ) that are kept the same and not allowed to changekept the same and not allowed to change

ExamplesExamples

1.1. One minute was consistently the amount of time One minute was consistently the amount of time allotted to perform the necessary activityallotted to perform the necessary activity

2.2. The type of activity performedThe type of activity performed

3.3. The stopwatch used during data collectionThe stopwatch used during data collection

4.4. The method used to measure the heart rateThe method used to measure the heart rate

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