Quiz 6 Flashcards
A ______ allows the researcher to obtain measurements for all members of a population.
census
A ______ shows how random sampling error shapes the expected values of sampling statistics.
sampling distribution
A large group of people of particular interest that we desire to study and understand, such as the people in a city or persons with jobs, is called a ______.
population
A particular number of cases drawn from the entire group a researcher wishes to study is known as a ______.
sample
A public opinion poll reporting the president’s job approval rating is an example of a ______.
sample statistic
A researcher studying the height of college freshmen determines the average height of males to be 5’10 with a standard deviation of 1.5 inches. John has a Z score of +1.96, which means John is what height?
6’1
A researcher who wants to reduce the magnitude of random sampling error in her study by half should ______.
quadruple the sample size
A Z score is a method used to ______ the scores in a normal distribution.
standardize
In a normal distribution ______ percent of all scores fall with two standard deviations of the mean.
95
In a normal distribution the portion of the curve above 1.96 standard errors is ______.
2.5 percent
In a normal distribution, a Z score of 1.96 tells us what?
how many standard deviations from the mean a sample mean is located
In statistical notation, the letter n refers to the ______.
sample size
In statistical notation, the symbol σ refers to the ______.
standard deviation
Random sampling error is defined as the extent to which a sample statistic differs from a population parameter by ______.
chance
Researchers study small groups of units of analyses to learn about the characteristics of a ______.
population
The average amount given to a political candidate is an example of a ______.
population parameter
The interval within which 95 percent of all possible sample estimates will fall by chance is defined as ______.
the sample mean ±1.96 standard errors
The level of random sampling error in a study is directly related to the ______ in the population characteristic.
variation
The magnitude of random sampling error in a study depends upon the ______ of a sample and the amount of ______ in the population characteristic being measured
size; variation
The US Census is an example of a ______.
population
A normally distributed set of sample means resembles a standard bell curve.
True
A probability is defined as the likelihood of the occurrence of an event or set of events.
True
A researcher working with a sample size of 35 should use the Student’s t distribution to make inferences about the population mean.
True
A standardized value is called a Z value or Z score.
True