Statistics, chapter 5,6 quiz

Statistics is the science of collecting, organizing, analyzing, and interpreting data in order to make ________

Decisions

A population is a collection of ______ outcomes, responses, measurements or counts that are of interest.

All

A sample is a representative ________of the population.

Subset

A parameter is a numerical measurement from a _________.

Population

A statistic is a numerical measurement from a __________.

Sample

A statistic describes ___________ data.

Sample

A parameter describes ___________ data.

population

The best point estimate of a population parameter is a _________ __________.

Sample Statistic

The __________ of a data set is effected by extreme values and is a measurement of the center of the data.

Mean

The three characteristics need to describe a data set are _________ __________ _________.

Mean, Median, Mode

The Standard deviation measures the ___________ of the data.

Spread

The standard deviation is the measurement of the _________ deviation from the _________.

Average, Mean

In a nirmal distribution, _________% of the data is within one standard deviation.

68%

In a ___________ distribution 99.7 of the data is within three standard deviations of the mean.

Normal

In a skewed distribution _________% of the data is within 3 standard deviations of the mean.

88.9

The best point estimate of the population mean is the ____________.

Sample Mean

The sample standard deviation, s, is the best point estimate of the _______ ________ -_________

Population, Standard, Deviation

P(hat) is the best _________ estimate of the population parameter, _____.

Point, P

The best point estimate of the population standard deviation is the sample mean. , True or False

False

A 95% confidence interval is larger than a 90% confidence interval.

True

The CLT is a theorem that studies a collection of a sample statistics.

True

Delores wants to construct a 94% confidence interval around the mean using a z-score. Her critical value would be 1.88 True or False

True

A sample of 400 applicants for law school included 75 women. 74/400 describes a population parameter.
True or False

False

What is the best point estimate of the mean of the population?

Mean of the sample

Which of the following percents would be the smallest confidence interval? 99%, 95%, 90%, 98,%.

90%.

John wants to find a 95% confidence interval around the mean using the t-distribution when n= 18. What would the critical value be?

InvT(.025,17) = 2.110

The sampling distribution of the mean can be approximated by the normal distribution.

As the sample size (number of observations in each sample) gets large enough.

Which of the following is true regarding the sampling distribution of the mean for a large sample size?

It has a normal distribution with the same mean as the population.

For a sample of n=35, the sampling distributin of the mean will be approximately normally distributed.

Regardless of the shape of the population.

For a sample of n = 20, the sampling distributrion of the mean will be normally distributed.

Only if the population is normally distributed.

A 99% confidence interval estimate can be interpreted to mean that:

If all possible samples are taken and confidence interval estimates are developed. 99% of them would included the true population mean somewhere in their interval.

Sampling distributions describe the distribution of

Statistics

In the construction of confidence intervals, all other quantities are unchanged, an increase in the sample size will lead to _________interval.

a narrower

Other things being equal, as the confidence level for a confidence interval increases, the width of the interval increases. True or False.

True