Chapter 2: Research Strategies Flashcards
hypothesis
a prediction drawn from a theory
naturalistic observation
entering the field or natural environment to record the behavior of interest
structured observations
the investigator sets up a laboratory situation that evokes the behavior of interest so that every participant has an equal opportunity to display a response
event sampling
the observer records all of the instances of a particular behavior during a set time period
time sampling
the observer records whether or not certain behaviors occur during a sample of short time intervals
observer influence
the effects of the observer on the behavior studied
observer bias
When observers are aware of the purposes of a study, they may see and record what they expect to see rather than what participants actually do.
clinical interview
researchers use a flexible, conversational style to probe for the participant’s point of view.
structured interview
each individual is asked the same set of questions in the same way.
neurobiological methods
which measure the relationship between nervous system processes and behavior.
clinical/ case study method
brings together a wide range of information on one child, including interviews, observations, test scores, and sometimes neurobiological measures.
ethnography
ethnographic research is a descriptive, qualitative technique. But instead of aiming to understand a single individual, it is directed at understanding a culture or a distinct social group through participant observation.
reliability
refers to the consistency, or repeatability, of measures of behavior.
validity
they must accurately mea- sure characteristics that the researcher set out to measure.
internal validity
is the degree to which conditions internal to the design of the study permit an accurate test of the researcher’s hypothesis or question.
external validity
the degree to which their findings generalize to settings and participants outside the original study.
correlational designs
researchers gather information on individuals, generally in natural life circumstances, and make no effort to alter their experiences. Then they look at relationships between participants’ characteristics and their behavior or development.
correlation coefficient
a number that describes how two measures, or variables, are associated with each other.
experimental design
permits inferences about cause and effect because researchers use an evenhanded procedure to assign people to two or more treatment conditions.
independent variable
is the one the investigator expects to cause changes in another variable.
dependent variable
is the one the investigator expects to be influenced by the independent variable.
confounding variables
so closely associated that their effects on an outcome cannot be distinguished.
random assignment
participants are randomly assigned to treatment conditions. By using an unbiased procedure, such as drawing numbers out of a hat or flip- ping a coin, investigators increase the chances that participants’ characteristics will be equally distributed across treatment groups.
field experiments
researchers capitalize on opportunities to randomly assign participants to treatment conditions in natural settings.
natural/ quasi experiments
Treatments that already exist, such as different family environments, child-care centers, or schools, are compared. These studies differ from correlational research only in that groups of participants are carefully chosen to ensure that their characteristics are as much alike as possible
longitudinal design
participants are studied repeatedly at different ages, and changes are noted as they get older.
biased sampling
the failure to enlist participants who represent the population of interest.
selective attrition
Participants may move away or drop out for other reasons, and those who continue are likely to differ in important ways from those who drop out.
practice effects
with repeated testing, participants may become “test-wise.” Their performance may improve as a result of practice effects—better test-taking skills and increased familiarity with the test—not because of factors commonly associated with development.
cohort effects
Longitudinal studies examine the development of cohorts— children developing in the same time period who are influenced by particular cultural and historical conditions. Results based on one cohort may not apply to children developing at other times.
cross-sectional design
groups of people differing in age are studied at the same point in time.
sequential designs
in which they conduct several cross-sectional or longitudinal investigations (called sequences). The sequences might study participants over the same ages but in different years, or they might study participants over different ages but during the same years
microgenetic design
an adaptation of the longitudinal approach, pre- sents children with a novel task and follows their mastery over a series of closely spaced sessions. Within this “microcosm” of development, researchers observe how change occursr
risks-versus-benefits ratio
which involves weighing the costs to participants in terms of inconvenience and possible psychological or physical injury against the study’s value for advancing knowledge and improving conditions of life.
protection from harm
If there are any risks to the safety and welfare of participants that the research does not justify, then preference is always given to the research participants.
informed consent
people’s right to have all aspects of a study explained to them that might affect their willingness to participate
debriefing
in which the researcher provides a full account and justification of the activities, occurs after the research session is over.