Estimating Parameters
The best estimate for the population mean
What is sample mean?
Of 94 adults selected randomly from one town, 62 have health insurance. A 90% confidence interval for the proportion of all adults in the town who have health insurance with have this as the point estimate.
In a survey of 100 people, 56 said they like pepperoni on their pizza. This is the point estimate for a 95% confidence interval for the population proportion.
What is 0.56?
What are the four assumptions about your sample necessary to make inferences about the Population using the Normal Model?
Random, Independent, 10% Rule, Sufficiently Large
The best estimate for the population proportion
What is the sample proportion?
Of 94 adults selected randomly from one town, 62 have health insurance. A 90% confidence interval for the proportion of all adults in the town who have health insurance will have this as the critical value.
What is 1.645?
The critical value for this level of confidence is 1.96 when constructing a confidence interval for the population proportion
What is 95%?
The condition for a sample to be sufficiently large to estimate the population proportion.
nhatp>=10 and nhatq>=10
The point estimate of students who have jobs when 200 are surveyed and 140 answer yes to having a job
What is p = 0.70?
Of 94 adults selected randomly from one town, 62 have health insurance. A 90% confidence interval for the proportion of all adults in the town who have health insurance will have this as the standard error.
The level of confidence for this critical value is 99% when constructing a confidence interval for the population proportion
What is 2.576?
The conditions for a sample to be sufficiently large to estimate the population mean, given population standard deviation.
Population is assumed to be Normally distributed OR
n >= 30
These are the values needed to find the standard error of the population proportion
What is n and "p hat"?
Of 94 adults selected randomly from one town, 62 have health insurance. A 90% confidence interval for the proportion of all adults in the town who have health insurance is this.
What is (0.579, 0.740)?
This is the interpretation of a confidence interval of (0.154, 0.354) with a 99% level of confidence about adults in a town that smoke.
What is we are 99% confident that the true proportion of all adults in a town that smoke falls between 0.154 and 0.354?
The population proportion is believed to be 20%. What sample size is necessary for a 95% confidence interval to confirm this proportion within 3%.
A minimum sample of 683.
The standard error will reduce by a factor of 2 when we do this to the sample size
What is quadruple the sample size?
Of 94 adults selected randomly from one town, 62 have health insurance. A 90% confidence interval for the proportion of all adults in the town who have health insurance is interpreted as this.
What is we are 90% confident that the true proportion of all adults in the town who have health insurance falls between 0.579 and 0.740?
In a survey of 25 people, 10 said they don't like to listen to music while studying. This is a 95% confidence interval for the population proportion.
What is (0.208, 0.592)?
The confidence interval does this as the confidence level gets higher
What is the confidence interval gets wider?