Hw: CH 1 INTRODUCTION TO STATISTICS - CH 1.1 Overview
Why is a sample used more often than a population?
It is usually impossible to count the entire population.
Determine whether the data set is a population or a sample. Explain your reasoning. The salaries of 5 baseball players on a team of 25
Sample, because the collection of salaries for 5 baseball players is a subset of all baseball players on the team.
The two main branches of statistics are?
descriptive statistics and inferential statistics.
Determine whether the underlined value is a parameter or a statistic. The average score for a class of 28 students taking a calculus midterm exam was 72% - Is the value a parameter or a statistic?
parameter
A parameter is a numerical description of a _______ characteristic. A statistic is a numerical description of a ______ characteristic.
population, sample
In a recent study, volunteers who had 8 hours of sleep were three times more likely to answer questions correctly on a math test than were sleep-deprived participants. (a) Identify the sample used in the study. (b) What is the sample's population? (c) Which part of the study represents the descriptive branch of statistics? (d) Make an inference based on the results of the study.
(a) The sample is the responses of the volunteers in the study. (b) The population is the collection of the responses of all individuals who completed the math test. (c)The statement "three times more likely to answer questions correctly" is an example of descriptive statistics. (d) Individuals who are not sleep deprived will be more likely to answer math questions correctly than individuals who are sleep deprived.
In a poll, 1,004 men in a country were asked whether they favor or oppose the use of "federal tax dollars to fund medical research using stem cells obtained from human embryos." Among the respondents, 46% said that they were in favor. - Identify the population and the sample. -Identify the sample for the given problem
- Population: All men in the country - Sample: The 1,004 men selected
How is a sample related to a population?
A sample is a subset of a population.
T/F: A statistic is a measure that describes a population characteristic.
False. A statistic is a measure that describes a sample characteristic
T/F: A sample statistic will not change from sample to sample.
The statement is false. A sample statistic can change from sample to sample.