Term
|
Definition
| The value of a statistic that estimates the value of a parameter |
|
|
Term
|
Definition
| An interval of numbers for an unknown parameter |
|
|
Term
|
Definition
| The expected proportion of intervals that will contain the parameter if a large number of different samples is obtained |
|
|
Term
| Level of confidence is denoted |
|
Definition
|
|
Term
| The form of confidence intervals for a population mean |
|
Definition
| Point estimate +/- margin of error |
|
|
Term
|
Definition
| A measure of how accurate the point estimate is |
|
|
Term
| Margin of error depends on 3 factors |
|
Definition
1. Level of confidence
2. Sample size
3. Standard deviation of the population |
|
|
Term
| Inequality with mew in the middle |
|
Definition
| xbar-z(alpha/2)x(sigma/n^0.5) |
|
|
Term
|
Definition
|
|
Term
| A 95% confidence interval for a parameter means |
|
Definition
| 95% of all possible samples will result in an interval that includes the unknown parameter and 5% will not |
|
|
Term
|
Definition
| xbar-z(alpha/2)x(sigma/n^0.5) |
|
|
Term
|
Definition
| xbar+z(alpha/2)x(sigma/n^0.5) |
|
|
Term
|
Definition
| Minor departures from normality will not seriously affect the results |
|
|
Term
| Margin of error, E, in a confidence interval in which sigma is known = |
|
Definition
|
|
Term
| Sample size required to estimate the population mean mew with a 95% level of confidence |
|
Definition
| n = [(z(alpha/2)xsigma)/E]^2 |
|
|
Term
| 3 requirements for constructing CI's about mew if sigma is known |
|
Definition
1. Data must be obtained from a simple random sample
2. Data must be obtained from a population that is normally distributed or n>30
3. Population sd sigma is assumed to be known |
|
|
