Chapter 10: Field Experiments

field reserach

conducted in natural settings, is designed to address some of

the shortcomings of laboratory research.

field experiment

studying people's natural behavioral responses to manipulated independent variables in natural settings; The goal is to allow causal conclusions to be drawn from research conducted in natural settings

street theater strategy

Technique to implement the independent variable in a field experiment; to stage an incident or introduce an event that will be witnessed by virtually every person in the surrounding area

accosting strategy

Technique to implement the independent variable in a field experiment; to select a specific sub-

ject who then becomes the target for the experimental intervention

natural experiment

a natural event that acts as the independent variable; attempt to achieve naturalism in treatment and setting

Is a correlational study because the researcher does not manipulate the independent variable, cannot randomly assign research participants to conditions, and has little control over extraneous variables

quasi-experiment

An "as if" experiment; manipulating the independent variable in a natural setting using existing groups of people as the experimental and control groups

(E.g., villages in India randomly assigned to a vaccination condition)

Group comparison approach

Researcher establishes a treatment and a no-treatment group (e.g., no equivalent control group design)

Nonequivalent control group design

a quasi-experimental design that has at least one treatment group and one similar comparison group, but participants have not been randomly assigned to the two groups

Patched up quasi-experiments

In a quasi-experiment, when the research adds a

control group that can be used to rule out possible pre-existing group differences that might have influenced the dependent variable

Focal local controls

Type of control group; ensures that the control and treatment groups are as similar as possible on both location and important personal characteristics

Nested analysis of variance design

Students are not randomly assigned to schools, but schools are randomly assigned to either the experimental or control group

Time series approach

A single-case technique; researchers make a number of observations of the dependent variable, manipulate the independent variable, and make further observations of the dependent variable. The researchers then compare the level of the dependent variable before and after the manipulation of the independent variable

Interrupted time series design

A type of time series design; A baseline period is followed by a treatment that

"interrupts" the baseline, followed by a period of post-treatment observations

Equivalent time samples design

A type of time series design; withdrawing treatment and making

observations about behavior without the treatment. At a later point, the treatment is reintroduced and behavior is assessed again

Allows researchers to be more confident the effects aren't due to history, maturation, selection differences, etc

Control series design

A type of time series design; consists of an interrupted time series design with the addition of one or more control groups

Multiple time series design

A type of time series design; involves

including an additional treatment group that receives the treatment (or interruption) at a different time in the series than did the initial treatment group

(e.g., examining talking on cellphone effects based on when laws have gone into effect)

naturalistic observation

to study human behavior as it occurs in natural settings in response to natural events, uninfluenced by the researcher; goal is to maximize ecological validity

Not a single method but a SET of methods that vary along two dimensions

Two dimensions of naturalistic observation

1) degree of researchers participation

2) degree that the researcher hides their identity

Participant observation

Category of naturalistic research; when the researcher participates the research setting they are studying.

Has three types:

1) complete participation

2) participant as observer

3) observer as participant

4) nonparticipant observation

Complete participation

Participant observation strategy; when the researcher becomes a full member of the research setting (usually a group or community) without the other members of the setting being aware of the observer's role as researcher. The researcher interacts as intimately as possible with the other members of the setting in as many ways as possible

Participant as observer

Participant observation strategy; when the researcher participates fully in the research setting BUT does not use deception

Observer as participant

participant observation strategy; when the researcher enter into the research setting but interact with the other members of the setting no more than

is necessary to collect data.

Can be covert or overt

nonparticipant observation

Participant observation strategy; when the researcher avoids taking part in the research setting, merely watching what happens and recording the observations.

Can be covert or overt,

Coding

Transferring behavioural observations into useable data

Coding scheme

consists of a set of categories for

classifying behaviors and the rules for assigning the behaviors they observe to categories

Unit of analysis

constitutes a single, codable behavior — including criteria such as whether a behavior is present or absent or when the behavior begins and end

Manifest content

What is actually being observed

(E.g., a child hits, slaps, or strikes with body part above the waist)

Latent content

How coders interpret what they observe, therefore requires information on context

(E.g., slapping someone on the back could be seen as a form of aggression or as a friendly greeting between men)

Broad category

In a coding scheme, tempts to categorize all the behaviors found in a situation by using relatively few high-level categories and ignoring fine distinctions between similar behaviors

Narrow category

In a coding scheme, usesa relatively large number of categories to capture the behavior of interest

Cognitive biases

systematic errors in thinking that impacts observations

(E.g., selective attention, expectations, faults in memory recall)

Recordkeeping

Frequently writing down observations after an event