Unit 3 Vocab Flashcards
When a significant number of participants do not return their surveys. This could
result in bias.
Nonresponse bias
Every person or object of interest in a study
Population
Pick a sample and gather data about their past
Retrospective Study
The control treatment used in medical experiments.
Placebo
We must __________ aspects of the experiment that we believe will effect
response.
Control
A sample in which each group of n units has an equal chance of being selected
Simple Random Sample
When you randomly pick a starting point on a list and select every 5th person
thereafter.
Systematic Sampling
When individuals from a subgroup of the population are not represented
Undercoverage
When both those influencing the results and evaluating the results of an
experiment don’t know which treatment was applied to the participants.
Double Blind
When entire groups, which are representative of the population are chosen
randomly for a survey.
Cluster Sampling
A hopefully representative subset of the population
Representative Sampling
A combination of specific levels of the factors in an experiment. For example, a
new medication plus a high level of exercise.
Treatment
In an experiment, you need many subjects in order to assess the variation in
response and be confident our results are not just due to chance or other
variables.
Replication
Pick a sample and follow them into the future, observing and collecting data about
the sample.
Prospective Study
A data value (such as mean) attributed to the population or used as a value to
model the population.
Parameter
When the population is subdivided and random samples drawn from each group.
The groups should each represent a group characteristic which may influence
response.
Stratified Sampling
A variable that is used to group participants in an experiment before assigning
treatments.
Blocking Variable
When you can’t determine which variable is effecting the difference in the outcomes of an experiment, then the variables are …..
Counfounded
Anything in a survey design that influences the response
Response Bias
When the sample is the entire population, we call this a _______________
Census
A data value (such as mean) calculated from the sample.
Statistic
In this experimental design, you first divide the participants into groups based on a variable or characteristic that you believe will affect the response. Then you randomly assign to subjects from each group to treatments.
Randomized Blocking
Design
The individual persons or objects in the population or sample
Participant, Units, Subjects
The variables that are manipulated in an experiment are called the …
Factors
In an experiment, this evens out the effects of variables we cannot control or that we haven’t even thought of.
Randomization
The participants assigned to a baseline treatment level (not necessarily no
treatment) used for comparison purposes in an experiment are the
Control Group
The natural tendency of random samples to differ from each other
Sampling Variability
When either those influencing the results or evaluating the results of an
experiment don’t know which treatment was applied to the participants.
Single Blind
Conducting a survey when you have no control over who responds such as phone- in surveys
Voluntary Response Bias
Polls, questionnaires, interviews of a sample of the population are examples of
this.
Survey
Generic term for the participants, subject, or objects in an experiment.
Experimental Unit
When an observed difference is too large to be attributed to chance, we say that the difference is __________.
Statistically Significant
Manipulate the environment and study the effects on individuals or objects. This is
the only way to prove a cause and effect relationship between variables.
Experiment
A sample in which the statistics gathered mirror the population. The best way to
get this kind of sample is through a design that incorporates randomness
Representative Sample
When one variable influences another, we say that they have what kind of
relationship?
Cause and Effect
In this experimental design, all experimental units have an equal chance of
receiving any treatment. We do not group them by any common variable.
Completely Randomized
Design
A poor sampling method in which you choose subjects that are easy to find
Convenience Sampling
The list of individuals representing the population from which a sample is chosen
Sampling Frame
This type of variable is also called the factor in an experiment.
Explanatory Variable
