External Validity & Field Research

Voluntary participant

Respondents in a study who are aware that they are under investigation, but have made a conscious decision that the possible benefits involved outweigh the costs of being in the study.

Involuntary participant

 Participants who feel that they have been coerced to spend their time in an experimental investigation and may vent their displeasure by actively attempting to ruin the study.

Nonvoluntary participant

 Research respondents who do not feel their participation in a study was voluntary (see also Involuntary participants).

Good participant:

who attempts to determine the experimenter's hypotheses and attempts to confirm them

Negative participant

who also are interested in learning the study hypotheses so they can disconfirm them

Faithful participants

who are willing to cooperate with almost any of the experimenter's demands and follow instructions scrupulously, ignoring any hypotheses they might have formed about study expectations

Apprehensive participants

who worry the experimenter will use their performance to evaluate their intelligence, morality, etc., and respond to experimental demands accordingly

Mundane realism:

The degree to which various features of an experiment - instructions, treatments, and measurement operations - mirror real-world events that participants might encounter in their day-to-day experiences, rather than laboratory-specific operations.

Experimental realism

The degree to which an experiment has a real impact on participants during a study. Experimental arrangements of high realism induce participants to attend carefully to the task requirements.

Placebo effect:

An outcome that occurs as a function of participants' beliefs in the efficacy of a treatment, rather than the active effect of treatment itself

Experimenter bias:

recording, observation, and computation errors are troublesome; these effects can be detected and avoided

Experimental demand:

Techniques of inferring causal relations, in which participants' actions are affected by the controlled manipulation of variables determined by the researcher

Demand characteristics

The totality of all social cues communicated in a laboratory not attributable to the manipulation, including those emanating from the experimenter and the laboratory setting, which influence or alter participants' response

Double-blind procedures

A method in which both the participants and the researcher responsible for administering a study are made unaware of the experimental condition to which participants were assigned

Robustness:

An issue of external validity concerned with the extent an effect obtained in one research study can be replicated with different participants, operationalizations of the critical construct, and researchers

Ecological validity:

An aspect of external validity, referring to the extent to which an effect observed in a research study is typical or representative of a population.

Relevance:

An issue of external validity; it has to do with the question of whether an effect obtained in a study is pertinent to events or phenomena that actually occur in the real world

Field study:

Research conducted outside the laboratory; participants are studied in their own naturalistic environment or context

Exact replication

An attempt to reproduce the results of a previous study by using the same procedures, particularly the same operationalizations, to represent the same construct

Conceptual replication:

 An attempt to reproduce the results of a previous study by using different operational definitions to represent the same construct

Who is the typical research participant?

college sophomore.

How do volunteer differ from non-volunteers?

better educated, higher occupational status, higher need for approval, higher intelligence, better adjusted