LESSON 3 Flashcards
the group defined by the researcher’s specific interests.
Target Population
Individuals in a target population typically share ____ _______
one characteristic
the part of the target population that can be accessed by the researchers.
Accessible Population
[HOW DO WE MAKE SURE THAT THE STATISTICS AND INFERENCES CAN BE GENERALIZED TO THE POPULATION?]
The _______ of a sample refers to the extent to which the characteristics of the sample accurately reflect the characteristics of the population
representativeness
A _______ _______ is a sample with the same characteristics as the population.
representative sample
A ____ _____ is a sample with different characteristics from those of the population.
biased sample
[HOW DO WE MAKE SURE THAT THE STATISTICS AND INFERENCES CAN BE GENERALIZED TO THE POPULATION?]
_____ _____ or _____ _____ occurs when participants or subjects are selected in a manner that increases the probability of obtaining a biased sample.
Selection bias , sampling bias
The process of selecting
individuals for a study is
called _______.
sampling
Researchers have developed
a variety of different sampling methods (also called ____ _____or _____ ______).
sampling techniques , sampling procedures
TWO TYPES OF SAMPLING TECHNIQUE
probability sampling
non-probability sampling
the entire population is known, each individual in the population has a specifiable probability of
selection, and sampling occurs by a random process based on the
probabilities.
probability sampling,
the population is not completely
known, individual probabilities cannot be known, and the sampling method is based on factors such as commonsense or ease, with an effort to maintain representativeness and avoid bias.
non-probability sampling,
PROBABILITY SAMPLING TECHNIQUES
- Simple random sampling
- Systematic Sampling
- Stratified Random Sampling
- Proportionate Stratified Random Sampling
- Cluster Sampling
[SIMPLE RANDOM SAMPLING]
The basic requirement for ____ ______ is that each individual in the population has an equal chance of being selected.
random sampling
[SIMPLE RANDOM SAMPLING]
_____ means that no individual is more likely to be chosen than another.
Equality
[SIMPLE RANDOM SAMPLING]
A second requirement that is sometimes added is that each selection is ______ of the others.
independent
[SIMPLE RANDOM SAMPLING]
______ means that the choice of one individual does
not influence or bias the probability of choosing another
individual.
Independence
The basic requirement for random sampling is that each individual in the population has an equal chance of being selected. Equality means that no individual is more likely to be chosen than another. A second requirement that is sometimes added is that each selection is independent of the others. Independence means that the choice of one individual does not influence or bias the probability of choosing another individual.
SIMPLE RANDOM SAMPLING
The process of simple random sampling consists of the
following steps:
- Clearly define the population from which you want to select a
sample. - List all the members of the population.
- Use a random process to select individuals from the list.
TWO PRINCIPAL METHODS OF RANDOM SAMPLING
- Sampling with replacement
- Sampling without replacement
____ ______ is a type of probability sampling that is
very similar to simple random sampling.
Systematic sampling
____ ______
begins by listing all the individuals in the population, then randomly picking a starting point on the list. The sample is then obtained by moving down the list, selecting every nth name.
Systematic sampling
[STRATIFIED RANDOM SAMPLING]
We first identify the specific ______ (__ ____) to be
included in the sample.
subgroup (or strata)
[STRATIFIED RANDOM SAMPLING]
Then we select ______ random
samples from each of the pre-identified subgroups, using the same steps as in simple random sampling.
equal-sized
