Distinguish between probability and nonprobability sampling techniques. Provide examples
for each. What is one problem with nonprobability sampling that might influence external
validity?
What will be an ideal response?
In probability sampling, one obtains a sampling frame, or list of all people representing
the study population, such as the names of all children attending public schools in a
community. In order to draw a research sample, the investigator may recruit using a
random method, such as sending parental permissions letters to every 5th child named
on the list. In nonprobability sampling, we recruit whoever we can. For example, a
researcher may post flyers throughout the community advertising the study. The chief
risk is that the research sample may not be representative of the broader population,
which influences confidence regarding external validity.
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Which term refers to enduring changes to the brain's perceptual system that allow us to improve our responses to the environment?
A. memory B. perceptual adaptation C. environmental response D. perceptual learning
What is the evidence for structural damage in the brains of patients with schizophrenia? a. All patients with schizophrenia have smaller ventricles in their brains
b. In some patients with schizophrenia, there is an excess amount of "gray matter" in the cerebral cortex. c. The majority of patients with schizophrenia have enlarged ventricles in their brains. d. Many patients with schizophrenia have increased activity in the frontal lobes of the brain.
Darwin proposed that the facial expressions and emotions seen in both humans and animals were based on a common physiological system and thus reflected
a. social referencing. c. continuity of function. b. emotional recognition d. primary emotions
Bob is nine months old. Carol is nine years old. Ted is twenty-nine years old. Alice is ninety years old. Whose brain is most likely overproducing synapses?
A. Bob B. Carol C. Ted D. Alice