04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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Research MethodsTopic 2: The Methods of Science

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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Naturalistic observationWho is Ford Prefect?What is the Prime Directive?If you want to know about something,

without influencing the process itself (well as much as possible anyway)

Record everything!Non-interferenceUseful when you know little about a

population or phenomenonOSS

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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Correlational approachThis is a method of relating two or

more variables – mathematically (we get a degree of relation)

It does not have anything to do with causation

Ice cream and crime; shoe size and IQ; socks and serial killing.

There is no attempt at manipulationWhat is the value? It gives us clues

as to where cause MIGHT exist between variables.

Positive and negative correlation.

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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The experimental methodHypothesis

◦Is the idea or statement being tested in an experiment or study.

Experimental group◦The group receiving the treatment

Control group◦The group we are comparing to –

typically receives nothing.

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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Operational definitions• Define stopping a car.• Define overeating.• Define exercising. • Define happiness.• (measurement) The goal with an

operational definition is to make the instance so clear that anyone can observe it and that we all observe the occurrence at the same time. (reliable)

• (experimental) Defining the procedures in an experiment clearly enough to be followed by anyone that has the means to do so.

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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Independent VariablesSomething that has an effect on

something elseThis is the variable of interest in a

scientific studyTo be experimental:

◦ At least one group gets the IV (experimental)◦ At least one group does not (control)

Examples

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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Dependant VariablesThese are the things in a study

that are effected by the IVThis is what we measureExamplesThe difference between your

groups on the DV is the treatment effect.

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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ConfoundsThings that COULD explain the

treatment effect that are not part of the treatment.

There are an infinite number of these.

We minimize them by introducing experimental control.

But if we control too many things – the findings do not represent the real world.

Must find a balance.

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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ValidityA key to any experimenting is the

concept of validityWe are doing what we intend to do. We

are measuring what we intend to measure.◦ True and capable of being supported.

Internal validity◦ Is the study sound enough to detect the

effect we are predicting and trying to measure!

◦ Are there confounds? These threaten internal validity.

External validity ◦ Generalizability. ◦ Do the findings represent the real world or

are they only a reflection of the laboratory conditions?

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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ReliabilityThe same group of people

experiencing the same IV should produce the same results on a DV.

RepeatabilityTreatment reliability Measurement reliabilityA valid measure is reliable – but

not necessarily the converse.

04/10/2023 CEDP 321/322 Ryan Sain, Ph.D.

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Scientific attitudeFalsification

◦ We seek to show what is not the case!◦ It only takes one instance to destroy a

1000 years of common held belief.Testablity

◦ The thing we are interested in studying must be testable!

Skeptical◦ We should be skeptical about our results

Parsimony◦ Two explanations for a given event, the

more simple is likely correct.