Demand characteristics refers to a problem which can
distort research. Demand characteristics as used in experimental psychology, refers
to unintended features of the experiment which affect the results, thus compromising the internal validity of the study.
The term demand characteristic
is also used in the sociology of deviant behavior to
refer to those organizational features of work settings, other than the formal goals of
the organizations or principles such as due process or
fairness, which shape arrest decisions, plea bargaining, or jury deliberations.
Examples of demand
characteristics which police officers may attend to in making decisions on the street are
the informal expectations of police culture, their work
load, their need to accumulate overtime or organizational rules.
Demand Characteristic is a term
used in Cognitive Psychology to denote the situation where the results of an experiment
are biased because the experimenters' expectancies regarding the performance of the
participants on a particular task create an implicit demand for the participants to
perform as expected.
Demand Characteristic result as
we do not simply respond to a situation or context because the meaning of such a situation
or context is not given, but requires interpretation.
Aspects of a research program or
of a researchers conduct, or even appearance, may cause the subject to guess the rationale
of the study and to attempt to confirm the experimenters hypothesis.
The problem is that particular
cues in an experimental situation may communicate to subjects what is expected and what
the experimenter hopes to find. Subjects might do what they think is expected,
demanded, of them rather than respond in any other way.
Demand characteristics have a clear link to Evaluation Apprehension where subjects come to
experiments or interviews expecting the possibility that they will be evaluated. Subjects
may then behave in a way that is thought to project a favorable image of themselves.
symptomatology: the role of social expectancy and experimental demand characteristics
- Psychosomatic Medicine, Vol 47, Issue 1 35-45.
The purpose of this study was to examine the effects of experimental demand
characteristics and social expectancies on the report and experience of presumed menstrual
cycle-related moods and symptoms. Results indicated that women who were informed of the
interest in menstrual cycle symptomatology reported significantly more negative
psychologic and somatic symptoms at the premenstrual and menstrual phases than did the
women and men not so informed. It appears, therefore, that the report of stereotypic
menstrual cycle symptomatology is influenced by social expectancy and experimental demand
in body-size estimation in anorexia nervosa
The British Journal of Psychiatry 149: 113-118 (1986).
We asked 24 patients with anorexia nervosa and 30 normal controls to estimate their
body-size several times, each time using different instructions. The degree of
over-estimation was found to vary predictably with the wording of the instructions.
Informing the subject that she had made an error without specifying the direction of the
error resulted in reduced over-estimation on a subsequent trial, for both anorexics and
controls. 'Internally directed' instructions were associated with a greater degree of
over-estimation than 'external' instructions in both groups, but particularly in anorexic
subjects. Our results indicate the necessity of controlling the demand characteristics of
not effort: The role of backpacks in judging distance
Robert Russell, Frank H. Durgin Department of Psychology, Swarthmore College
Abstract: Does wearing a backpack increase perceived distance, or does it simply encourage
subjects to increase numerical estimates? A no-backpack control condition was also run.
Because subjects made judgments in two different virtual environments, we expected that
people in the control and implicit conditions would believe that the experiment concerned
possible differences between the two environments. However, we expected people in the
explicit backpack condition to believe that they were to judge distances as farther than
they were. Based on an earlier replication of the backpack experiment outdoors with a male
experimenter, we only expected to find evidence of demand characteristics compliance among
women subjects. We conclude that effects of backpacks on judgments of distance are
probably due exclusively to demand characteristics and not to any actual change in
perception when burdened.
and Inferential Processes in Psychotherapeutic Change.
Horvath, Peter - Journal of Consulting and Clinical Psychology, v52 n4 p616-24 Aug 1984
Abstract: A brief narrative description of the journal article, document, or resource.
Offers evidence that demand characteristics referring to changes in clients' self-concepts
are the common factors in psychotherapies. Unassertive subjects (N=87) were assigned to
four types of imaginary role playing. Only the demand characteristics condition increased
significantly in assertiveness and self-esteem and decreased significantly in social
discomfort compared to controls.
of residential substance abuse treatment programs
Christine Timko, Katherine Yua and Rudolf H. Moosa
Journal of Substance Abuse, Volume 12, Issue 4, Winter 2000, Pages 387-403
Abstract: Purpose: This study examined the objective demand characteristics of treatment
programs in which substance abuse patients, or psychiatric patients, were residing. It
also examined associations of objective demand with substance abuse patients' perceived
expectations for functioning during treatment and patients' in-program participation.
Methods: A total of 994 patients living in 79 programs took part. Results: When patients
had a substance abuse rather than a psychiatric problem, objective demand characteristics
was higher: program policies had higher requirements for functioning and more resident
control; programs offered fewer health-treatment services; and the physical design
provided fewer safety features and socialrecreational aids. Compared to substance
abuse patients in low-demand programs, patients in high-demand characteristics programs
perceived the program to have higher expectations, in that the treatment climate exerted
more press to develop relationships, set goals, and be organized. Patients in high-demand
programs engaged more in self-initiated activities and participated more in treatment
services and program-organized events. Substance abuse patients' activity and
participation levels were determined jointly by the level of demand characteristics and by
the expectations for patients' expressiveness and self-understanding of their personal
problems. Implications: The findings illustrate the importance of considering objective
indices of demand in conjunction with perceived expectations to improve patients'
in Assessing Motion Sickness in a Virtual Environment: Or Does Taking a Motion Sickness
Questionnaire Make You Sick?
Authors Sean D. Young, Bernard D. Adelstein, Stephen R. Ellis
Publisher IEEE Educational Activities Department Piscataway, NJ, USA
ABSTRACT: The experience of motion sickness in a virtual environment may be measured
through pre and postexperiment self-report studies
such as the Simulator Sickness Questionnaire (SSQ). Although research provides converging
evidence that users of virtual environments can experience motion sickness, there have
been no controlled studies to determine to what extent the user's subjective response is a
demand characteristic resulting from pre and posttest measures. In this study, subjects
were given either SSQ's both pre and postvirtual environment immersion, or only
postimmersion. This technique tested for contrast effects due to demand characteristics in
which administration of the questionnaire itself suggested to the participant that the
virtual environment may produce motion sickness. Results indicate that reports of motion
sickness after immersion in a virtual environment are much greater when both pre and
postquestionnaires are given than when only a posttest questionnaire is used. The
implications for assessments of motion sickness in virtual environments are discussed.
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