It is approximately normal as long as np 5 and n(1-p) 5.
What describes the form of the sampling distribution of the sample proportion?
n-1
the degrees of freedom for the t distribution equals
becomes smaller
When the level of confidence decreases, the margin of error
The sample must have a normal distribution.
A sample of 20 items from a population with an unknown ? is selected in order to develop an interval estimate of ?. Which of the following is not necessary?
a population parameter
An interval estimate is a range of values used to estimate
the size of the confidence interval to increase
If we change a 95% confidence interval estimate to a 99% confidence interval estimate, we can expect?
Increase the sample size.
After computing a confidence interval, the user believes the results are meaningless because the width of the interval is too large. Which one of the following is the best recommendation?
becomes narrower
A 95% confidence interval for a population mean is determined to be 100 to 120. If the confidence coefficient is reduced to 0.90, the interval for ?
p=0.50
For which of the following values of P is the value of P(1 - P) maximized?
t distribution with 24 degrees of freedom
From a population that is normally distributed, a sample of 25 elements is selected and the standard deviation of the sample is computed. For the interval estimation of ?, the proper distribution to use is the?
normal distribution
A sample of 200 elements from a population with a known standard deviation is selected. For an interval estimation of ?, the proper distribution to use is the?
The sample size must be increased.
From a population that is not normally distributed and whose standard deviation is not known, a sample of 6 items is selected to develop an interval estimate for the mean of the population (?).
the sample standard deviation can be used
In developing an interval estimate, if the population standard deviation is unknown
the sample standard deviation is used to estimate the population standard deviation
In interval estimation, the t distribution is applicable only when?
0.9
If an interval estimate is said to be constructed at the 90% confidence level, the confidence coefficient would be?
Margin of error
The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as the?
The normal distribution
For the interval estimation of ? when ? is known and the sample is large, the proper distribution to use is?
Population
The set of all elements of interest in a study is?
is the probability distribution showing all possible values of the sample mean
The sampling distribution of the sample means?
reduce the standard error of the mean to approximately 70% of its current value
Doubling the size of the sample will?
A subset of a population
A sample is?
approximately normal if np 5 and n(1-P) 5
A sample of 25 observations is taken from an infinite population. The sampling distribution of p is
point estimate
A simple random sample of 28 observations was taken from a large population. The sample mean equaled 50. Fifty is a
Central limit theorem
A theorem that allows us to use the normal probability distribution to approximate the sampling distribution of sample means and sample proportions whenever the sample size is large is known as the?
a point estimate
A single numerical value used as an estimate of a population parameter is known as
standard error
The standard deviation of a point estimator is called the?
a sampling distribution
A probability distribution for all possible values of a sample statistic is known as?
The sampling distribution of x
The probability distribution of all possible values of the sample mean x is?
difference between the value of the sample mean and the value of the population mean
The sampling error is the?
normal distribution
As the sample size becomes larger, the sampling distribution of the sample mean approaches a?
Standard error of the mean
The standard deviation of all possible x values is called the?
The population mean
The sample mean is the point estimator of?
standard error of the mean decreases
As the sample size increases, the
the smaller the sampling error
The closer the sample mean is to the population mean
judgment sampling
Which of the following is an example of nonprobabilistic sampling?
Sampling distribution of p
The probability distribution of all possible values of the sample proportion p is the