what is an interval estimate course hero

What is interval estimation?

Interval estimation is the use of sample data to calculate an interval of possible (or probable) values of an unknown population parameter, in contrast to point estimation, which is a single number.

How many measurements are needed for 95% interval estimation?

To achieve 95% interval estimation for the mean boiling point with total length less than 1 degree, the student will have to take 23 measurements.

What is the margin of error m of interval estimation?

The margin of error m of interval estimation is defined to be the value added or subtracted from the sample mean which determines the length of the interval: Suppose in the example above, the student wishes to have a margin of error equal to 0.5 with 95% confidence.

What is the critical value for 95% confidence interval?

The student calculated the sample mean of the boiling temperatures to be 101.82, with standard deviation σ = 0.49. The critical value for a 95% confidence interval is 1.96, where 1 − 0.95 2 = 0.025.

What is an interval estimate used to estimate?

An interval estimate is a single value used to estimate a population parameter. An interval estimate is a range of values used to estimate a population parameter. Approximately 96 out of 100 such intervals would include the true value of the population parameter.

Which of the following best describes the purpose of a confidence interval?

To estimate the sample statistic we would expect to get when taking = random sample from a population: To see ifan assumed value of a population parameter Is plausible or not; using an observed statistic value as evidence.

What is the confidence associated with an interval estimate?

For both continuous and dichotomous variables, the confidence interval estimate (CI) is a range of likely values for the population parameter based on: the point estimate, e.g., the sample mean. the investigator's desired level of confidence (most commonly 95%, but any level between 0-100% can be selected)

Which of the following best represents the point estimate of the population mean?

The best point estimate for the population mean is the sample mean, x . The best point estimate for the population variance is the sample variance, 2 s .

What is confidence interval quizlet?

A confidence interval measures the probability that a population parameter will fall between two set values. A confidence interval is the probability that a value will fall between an upper and lower bound of a probability distribution.

What is the purpose of a confidence interval quizlet?

The purpose of confidence intervals is to give us a range of values for our estimated population parameter rather than a single value or a point estimate. The estimated confidence interval gives us a range of values within which we believe, with varying degrees of confidence, that the true population value falls.

What is are the differences between random estimation and confidence interval estimate?

Point estimation gives us a particular value as an estimate of the population parameter. . Interval estimation gives us a range of values which is likely to contain the population parameter. This interval is called a confidence interval.

Why is the interval estimate a preferred value for the population parameter?

Interval estimation is the range of numbers in which a population parameter lies considering margin of error. Because there is a certain level of uncertainty, an interval estimate gives a range, rather than a single value, of the population parameters.

What does 95 confidence interval represent?

The 95% confidence interval defines a range of values that you can be 95% certain contains the population mean. With large samples, you know that mean with much more precision than you do with a small sample, so the confidence interval is quite narrow when computed from a large sample.

What best describes a point estimate?

Point estimators are functions that are used to find an approximate value of a population parameter from random samples of the population. They use the sample data of a population to calculate a point estimate or a statistic that serves as the best estimate of an unknown parameter of a population.

What is a point estimate in statistics?

point estimation, in statistics, the process of finding an approximate value of some parameter—such as the mean (average)—of a population from random samples of the population.

Which one of the following is an example of point estimate?

A population mean is an example of a point estimate.

Interval Estimation: An Overview, and a How-to Guide for Practitioners

Suppose you know the mean value of a sample and you want to use the sample mean to estimate the interval that the population’s mean will lie in. The Interval Estimation technique can be used to arrive at this estimate at some specified confidence level.

Estimating the interval for the population mean

Let’s illustrate the process of interval estimation using a real world data set.

Applicability of Interval Estimation to Regression Modeling

When you train a regression model, the coefficients of the regression variables acquire their ‘fitted’ values as follows:

Formula

Suppose a student measuring the boiling temperature of a certain liquid observes the readings (in degrees Celsius) 102.5, 101.7, 103.1, 100.9, 100.5, and 102.2 on 6 different samples of the liquid. He calculates the sample mean to be 101.82.

Margin of Error

The margin of error m of interval estimation is defined to be the value added or subtracted from the sample mean which determines the length of the interval: