what is an interval estimate course

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. Formula μ = x ¯ ± Z α 2 σ n Where − x ¯ = mean Z α 2 = the confidence coefficient α = confidence level σ = standard deviation

Full Answer

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 can I assess my understanding of point and interval estimations?

If you're in the process of studying point and interval estimations and want to find out how much you understand, these assessment tools can help! Take the short quiz or complete the printable worksheet to measure your comprehension of populations, mathematics tools and ranges of numbers as they relate to these estimations.

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 point estimate of the confidence interval?

The point estimate is simply the midpoint of the confidence interval. For more on mean, median and mode, read our tutorial Introduction to the Measures of Central Tendency .

What is interval estimation?

interval estimation, in statistics, the evaluation of a parameter—for example, the mean (average)—of a population by computing an interval, or range of values, within which the parameter is most likely to be located.

What is an example of interval estimates?

Interval estimates aim at estimating a parameter using a range of values rather than a single number. For example, the proportion of people who voted for a particular candidate is estimated to be 43% with a margin of error of three (3.0) percentage points based on a political poll.

How do you do interval estimates?

There are four steps to constructing a confidence interval.Identify a sample statistic. Choose the statistic (e.g, sample mean, sample proportion) that you will use to estimate a population parameter.Select a confidence level. ... Find the margin of error. ... Specify the confidence interval.

What does an interval estimate provide?

An interval estimate gives you a range of values where the parameter is expected to lie. A confidence interval is the most common type of interval estimate.

Why is interval estimation important?

A major advantage of using interval estimation is that you provide a range of values with a known probability of capturing the population parameter (e.g., if you obtain from SPSS a 95% confidence interval you can claim to have 95% confidence that it will include the true population parameter.

What are the two types of estimates?

There are two types of estimates: point and interval.

How does an interval estimate differ from a point estimate?

The main difference between point and interval estimation is the values that are used. Point estimation uses a single value, the statistic mean, while interval estimation uses a range of numbers to infer information about the population.

What is an interval estimate quizlet?

interval estimate. an estimate of population parameter that provides an interval believed to contain the value of the parameter.

What is the advantage of the interval estimate over the point estimate?

Advantages of Interval Estimation over Point Estimation An interval estimate (i.e., confidence intervals) also helps one to not be so confident that the population value is exactly equal to the single point estimate. That is, it makes us more careful in how we interpret our data and helps keep us in proper perspective.

Why do statisticians prefer interval estimates?

Statisticians prefer interval estimates because interval estimates are accompanied by a statement concerning the degree of confidence that the interval contains the population parameter being estimated. Interval estimates of population parameters are called confidence intervals.…

What is the interval of a population parameter?

Intervals are commonly chosen such that the parameter falls within with a 95 or 99 percent probability, called the confidence coefficient. Hence, the intervals are called confidence intervals; the end points of such an interval are called upper and lower confidence limits. The interval containing a population parameter is established by calculating ...

What is the difference between interval estimation and point estimation?

The main difference between point and interval estimation is the values that are used . Point estimation uses a single value, the statistic mean, while interval estimation uses a range of numbers to infer information about the population. Estimation is used in statistics to infer information on gathered data.

What are the two types of estimation?

There are two types of estimations used: point and interval. A point estimation is a type of estimation that uses a single value, a sample statistic, to infer information about the population. A sample is a part of a population used to describe the whole group.

What is point estimation?

A point estimation is a type of estimation that uses a single value, a sample statistic, to infer information about the population. Point estimation can be a sample statistic. The sample mean of age for the sample, 32, can be used as a point estimation.

What is a parameter in statistics?

A parameter is the characteristics used to describe a population. You can use a sample statistic to develop population parameters.

What is Cat's degree?

Cat has taught a variety of subjects, including communications, mathematics, and technology. Cat has a master's degree in education and is currently working on her Ph.D. Statisticians have to use estimation to describe and infer information from gathered data.

What is a statistic in statistics?

A statistic is the characteristics of a sample used to infer information about the population. For example, Anna may include questions on her survey such as age and number of pets. If the mean age for her sample is 32, then 32 is a sample statistic. She might infer that the average age of the people in town is also 32.

About This Quiz & Worksheet

If you're in the process of studying point and interval estimations and want to find out how much you understand, these assessment tools can help! Take the short quiz or complete the printable worksheet to measure your comprehension of populations, mathematics tools and ranges of numbers as they relate to these estimations.

Additional Learning

Accompanying this quiz and worksheet is a lesson called Point & Interval Estimations: Definition & Differences. By exploring this lesson, you can learn more about the following:

How to find the confidence interval?

The formula for all confidence intervals is: FROM the point estimate - the reliability factor * the standard error TO the point estimate + the reliability factor * the standard error.

What is the point estimate?

Now, about the relation between a confidence interval and a point estimate. The point estimate is simply the midpoint of the confidence interval.

How reliable are point estimators?

Point estimators are not very reliable, as you can guess. Imagine visiting 5% of the restaurants in London and saying that the average meal is worth 22.50 pounds. You may be close, but chances are that the true value isn’t really 22.50 but somewhere around it.

What is the level of confidence?

The Level of Confidence. There is one more ingredient needed: the level of confidence. It is denoted by: 1 - alpha, and is called the confidence level of the interval. Alpha is a value between 0 and 1. For example, if we want to be 95% confident that the parameter is inside the interval, alpha is 5%. If we want a higher confidence level of, say, ...

Is a point estimate a confidence interval?

A point estimate is a single number. Whereas, a confidence interval, naturally, is an interval. The two are closely related. In fact, the point estimate is located exactly in the middle of the confidence interval. However, confidence intervals provide much more information and are preferred when making inferences.

Do confidence intervals have an edge over point estimates?

That’s when you’ll realize that confidence intervals actually have an edge over point estimates.