Exam #2 chapter 6
time of measurement
the scores of individuals are measured at a specific time after or during the treatment. Might look more successful right after the experiment but fade as time goes on. Example: smoking prevention
3 threats to external validity (generalizability)
1. Generalization from a sample to the general population 2.Generalization from one research study to another 3.Generalization from a research study to a real-world situation
correlational research strategy
A general approach to research that involves measuring two or more variables for each individual to describe the relationship between the variables. The measurements are reviewed to identify any patterns of relationship that exist between the variables and to measure the strength of the relationship; however, no attempt is made to explain the relationship.
linear relationships
A relationship that has a straight line graph
novelty effect
A threat to external validity that occurs when individuals participating in a research study (a novel situation) perceive and respond differently than they would in the normal, real world. Anxiety or excitement hinder their responses/behaviors
demand characteristics
Any aspects of a study that communicate to the participants how the experimenter wants them to behave.
Time-related variables
Environmental or participant variables that change over time. A threat to the internal validity of studies that compare measures of the same individuals taken at different times.
A research study attempts to describe the relationship between self-esteem and both order position by measuring self-esteem for each individual in a group of first-born boys and then comparing the results with self-esteem scores for a group of later-born boys. Which result strategy is being used?
Nonexperimental
cross-species generalizations
Research on nonhumans presumed applicable to humans
research procedure
The exact, step-by-step description of a specific research study.
How can sensitization threaten external validity of a study?
The results might be limited to individuals who have experienced a pretest
Both correlational and nonexperimental studies intend to examine relationships between variables without trying to explain the relationships. T or F
True
College students are used very often for research? T or F
True
which of the following questions can be addressed with the descriptive study?
What is the average number of text messages that a typical adolescent sends in a month?
Can a study have one validity and not the other?
Yes; a study can be strong in only one type of validity but not the other
research strategy
a general approach to research determined by the kind of question that the research study hopes to answer
experimenter bias
a phenomenon that occurs when a researcher's expectations or preferences about the outcome of a study influence the results obtained
Which of the following is a general plan for implementing a research strategy?
a research design
negative relationships
an association between two variables in which one increases while the other decreases
artifact
an external factor that may influence or distort measurements can threaten both validity and reliability 1. experimenter bias 2. participant reactivity
In which research situation would the study be confounded?
an extraneous variable varies systematically along with two variables being studied
a threat to external validity
any characteristic of a study that limits the ability to generalize the results from a research study
threat to internal validity
any factor that allows for an alternative explanation
extraneous variable
any variable in a research study other than the specific variables being studied
postive relationships
as one variable increases the other variable increases as well
In research studies that compare different groups of individuals for each of the treatment conditions, ____ is a threat to internal validity.
assignment bias
quasi-experimental research
attempt to produce a cause-and-effect explanation but fall short DATA: measure before/after scores for one group that receives a treatment and for a different group that does not receive the treatment
Experimental Characteristics
can affect the external validity
multiple treatment interference: fatigue and practice
can occur in one treatment and then affect performance in the following treatment
participant variables
characteristics such as age, gender, and intelligence that vary from one individual to another
A study examining the relationship between humor and memory compares memory performance scores for one group presented with humorous sentences and a second group presented with non humorous sentences. The participants in one group are primarily 10-year-old students. In this study, age is potentially a ________ variable.
confounding
A research study records a score measuring Facebook use and a score measuring happiness level for each individual in a group of 20-year-old women. The study intends to determine whether there is a relationship between the two variables. This study is best characterized as ____ research.
correlational
Cues given to participants about how they are expected to behave define which of the following terms?
demand characteristics
Results from a research study suggest that a stop-smoking program is very successful. However, the participants who volunteered for the study were all highly motivated to quit smoking and the researcher is concerned that the same results may not be obtained for smokers who are not as motivated. What kind of validity is being questioned?
external validity
The degree to which your research results generalize beyond the specific characteristics of your study refers to ____.
external validity
the degree to which your research results generalize beyond the specific characteristics of your study refers to
external validity
Which of the following describes a variable that exists in a study but is not being directly examined?
extraneous
Curvilinear
formed, bound, or characterized by curved lines
experimental research studies tend to have very _______ internal validity but often have relatively ______ external validity.
high; low
internal validity
if it produces a single, unambiguous explanation for the relationship between two variables
field
individuals are observed inn their natural environment and are much less likely to know that they are being investigated
Sensitization can threaten external validity because the results obtained in a study may be limited to ____.
individuals who have experienced a pretest
nonexperimental research strategy
intended to demonstrate a relationship between variables but it does not attempt to explain the relationship
What aspect of a study is threatened if the participants are tested in one treatment condition at one time and in a second treatment condition at a different time?
internal validity
A study is ____ if it produces only one explanation for the results.
internally valid
research design
is a general plan for implementing a research strategy. A research design specifies whether the study will involve groups or individual participants, will make comparisons within a group or between groups and how many variables will be included in the study
confounding variable
is an extraneous variable (usually unmonitored) that changes systematically along with the two variables being studied. A confounding variable provides an alternative explanation for the observed relationship between the two variables and, therefore, is a threat to internal validity
When research is conducted in a ____, participants are not influenced by ____.
laboratory; reactivity
generality across response measures
many variables can be defined and measured in different ways
A researcher designs a study to determine whether female preschoolers prefer sweetened or unsweetened cereal. The researcher first presents the children with the sweet cereal and measures how much they ate. Later, during the same session, the researcher presents the children with the unsweetened cereal and measures how much they ate. The research finds that the group of preschoolers ate more of the sweetened cereal and therefore prefers the sweetened cereal. Is this conclusion justified?
no; this conclusion is not justified. Time-related variables could threaten the results
this threat to external validity occurs whenever a study uses participants who share similar characteristics
participant characteristics
participant reactivity
participants act differently or unnaturally because they know someone is watching them
lab
participants are fully aware that they are participating in a study
experimental research
produce a cause-and-effect explanation for the relationship between two variables DATA: create two treatment conditions by changing the level of one variable. Then measure a second variable for the participants in each condition
descriptive research
produce a description of individual variables as they exist within a specific group DATA: a list of scores obtained by measuring each individual in the group being studied
Nonexperimental
produce a description of the relationship between two variables but do not attempt to explain the relationship DATA: measure scores for two different groups of participants or for one group at two different times
correlational research
produce a description of the relationship between two variables but do not attempt to explain the relationship DATA: measure two variables (two scores) for each individual in the group being studied
selection bias
sampling procedure favors the selection of some individuals over others
Single Blind vs. Double Blind
single= participants don't know which group they are assigned to double= resarchers nor participants know
A research ____ is a general approach that is intended to address a specific question.
strategy
volunteer bias
the concept that people who volunteer to participate in research studies often differ from those who do not volunteer they are not a perfect representation of the general population either
multiple treatment interference
the effects of one treatment on a subject's behavior being confounding by the influence of another treatment administered in the same study
external validity
the extent to which the results of a study can be generalized to other situations and to other people
A journal article reports that a new teaching strategy is very effective for 1st grade students. A teacher wonders if the same strategy would be effective for a class of 3rd grade students. What is the teacher questioning?
the external validity of the report
descriptive research strategy
the goal of the descriptive strategy is to obtain a snapshot of specific characteristics of a specific group of individuals. Concerned with the description of individual variables
individual differences
the individuals in a research study differ on a variety of participant variables such as age, height, weight, IQ, and personality. The differences from one participant to another
sensitization or assessment sensitization
threat to external validity because it raises the question of whether the results obtained in a research study using assessment are different from results in the real world, where the treatment is used without assessment
pretest sensitization
threat to external validity; the situation that occurs when completing a pretest affects participants' responses on the posttest