The Experimental MethodThe Experimental Method

(Psychology version)(Psychology version)

Design types used in psychology researchDesign types used in psychology research

Observation• Watch unobtrusively

Survey• Ask questions

Experiment• Manipulate the situation

Observation• Watch unobtrusively

Survey• Ask questions

Experiment• Manipulate the situation

ObservationObservation

Ruback & Juieng (1997)• Do people exhibit territoriality in the

parking lot by taking longer to back out of parking spaces when a car is waiting?

Ruback & Juieng (1997)• Do people exhibit territoriality in the

parking lot by taking longer to back out of parking spaces when a car is waiting?

• Complete this mini-survey using the scale below:

faster just as fast more slowly1 2 3 4 5 6 7

1. If I am backing out of a parking space and someone is waiting, I will back out: ____

• Complete this mini-survey using the scale below:

faster just as fast more slowly1 2 3 4 5 6 7

1. If I am backing out of a parking space and someone is waiting, I will back out: ____

faster just as fast more slowly1 2 3 4 5 6 7

2. If I am backing out of a parking space and someone is waiting and that driver honks the horn at me, I will back out: ____

faster just as fast more slowly1 2 3 4 5 6 7

2. If I am backing out of a parking space and someone is waiting and that driver honks the horn at me, I will back out: ____

faster just as fast more slowly1 2 3 4 5 6 7

3. If someone else is backing out of a parking space and someone is waiting, the person will back out: ____

faster just as fast more slowly1 2 3 4 5 6 7

3. If someone else is backing out of a parking space and someone is waiting, the person will back out: ____

faster just as fast more slowly1 2 3 4 5 6 7

4. If someone else is backing out of a parking space and someone is waiting and that driver honks the horn, the person will back out: ____

faster just as fast more slowly1 2 3 4 5 6 7

4. If someone else is backing out of a parking space and someone is waiting and that driver honks the horn, the person will back out: ____

Ruback & Juieng results

Ruback & Juieng results

• Observation design:• Watch people backing out of parking spaces

and record what happens.• 39 sec with a car waiting, 32 sec without.

• Observation design:• Watch people backing out of parking spaces

and record what happens.• 39 sec with a car waiting, 32 sec without.

SurveySurvey

Landrum (1999)• Do students have an expectation of

grade inflation?

Landrum (1999)• Do students have an expectation of

grade inflation?

• Think of a course you have taken recently. Rate the quality of your work in that course using the following scale:• Distinguished• Superior• Average• Below-average• Failure

• Think of a course you have taken recently. Rate the quality of your work in that course using the following scale:• Distinguished• Superior• Average• Below-average• Failure

• For the same course, what grade did you deserve?• A• B• C• D• F

• For the same course, what grade did you deserve?• A• B• C• D• F

Landrum resultsLandrum results

• Landrum converted responses to his questions to GPAs:• Mean GPA for quality of work: 2.43• Mean GPA for expected grade: 3.03• The difference was significant

• Landrum converted responses to his questions to GPAs:• Mean GPA for quality of work: 2.43• Mean GPA for expected grade: 3.03• The difference was significant

Comparing observation and survey designs

Comparing observation and survey designs

• On surveys:• People lie to look good• People don’t actually know the answer• People’s retrospective memory is really bad

• For observation:• People are actually doing it• They’re doing it• It’s happening right now

• On surveys:• People lie to look good• People don’t actually know the answer• People’s retrospective memory is really bad

• For observation:• People are actually doing it• They’re doing it• It’s happening right now

Comparing observation and survey designs

Comparing observation and survey designs

• For example:• Ruback and Juieng found that people take longer in

the mild intrusion condition (car waiting, no honking). However, on their survey (like the one we just did), people responded that they would back out faster.

• I just asked you to rate your performance and expected grade in a previous class. Now that you know your grade, can you really remember your expected grade? Hindsight bias research suggests that you can’t.

• For example:• Ruback and Juieng found that people take longer in

the mild intrusion condition (car waiting, no honking). However, on their survey (like the one we just did), people responded that they would back out faster.

• I just asked you to rate your performance and expected grade in a previous class. Now that you know your grade, can you really remember your expected grade? Hindsight bias research suggests that you can’t.

Evaluating observation and survey designs

Evaluating observation and survey designs

• For both designs, we can’t explain causes of behavior. For example:• Do people take longer to back out because they’re

territorial or because it’s more dangerous when other cars are around?

• Why do people have an expectation of grade inflation? (Because they typically get more than they earn or because they’ve adopted a consumer model and think of grades as the product they’re paying for?)

• For both designs, we can’t explain causes of behavior. For example:• Do people take longer to back out because they’re

territorial or because it’s more dangerous when other cars are around?

• Why do people have an expectation of grade inflation? (Because they typically get more than they earn or because they’ve adopted a consumer model and think of grades as the product they’re paying for?)

ExperimentExperiment

Foertsch & Gernsbacher (1997)• Is the pronoun he used generically

really gender neutral?

Foertsch & Gernsbacher (1997)• Is the pronoun he used generically

really gender neutral?

• The use of he as a pronoun for nouns embracing both genders is a simple, practical convention rooted in the beginnings of the English language. He has lost all suggestion of maleness in these circumstances.... It has no pejorative connotations; it is never incorrect. (Strunk & White, 1979, p. 60)

• In speech we often solve the problem of the generic he by [using] a plural pronoun...as in Everyone brought their books to class. But this construction violates the expectations of most readers, so it should be avoided in writing. (Fowler & Aaron, 1983, p. 195)

• The use of he as a pronoun for nouns embracing both genders is a simple, practical convention rooted in the beginnings of the English language. He has lost all suggestion of maleness in these circumstances.... It has no pejorative connotations; it is never incorrect. (Strunk & White, 1979, p. 60)

• In speech we often solve the problem of the generic he by [using] a plural pronoun...as in Everyone brought their books to class. But this construction violates the expectations of most readers, so it should be avoided in writing. (Fowler & Aaron, 1983, p. 195)

• A truck driver should never drive when sleepy,

• even if he/she/they may be struggling to make a delivery on time,

• because many accidents are caused by drivers who fall asleep at the wheel.

• A truck driver should never drive when sleepy,

• even if he/she/they may be struggling to make a delivery on time,

• because many accidents are caused by drivers who fall asleep at the wheel.

• A nurse should have an understanding of how a medication works,

• even if he/she/they will not have any say in prescribing it,

• because nurses must anticipate how a patient will respond to the medication.

• A nurse should have an understanding of how a medication works,

• even if he/she/they will not have any say in prescribing it,

• because nurses must anticipate how a patient will respond to the medication.

Foertsch and Gernsbacher results

Foertsch and Gernsbacher results

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50

52

54

56

58

60

Masculine Feminine

HeSheThey

48

50

52

54

56

58

60

Masculine Feminine

HeSheThey

ConclusionsConclusions

• The choice of method depends on the question, keeping in mind:• Ethics• Feasibility

• The choice of method depends on the question, keeping in mind:• Ethics• Feasibility