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How do you find the 95% confidence interval for the population proportion?

How do you find the 95% confidence interval for the population proportion?

This can also be found using appropriate commands on other calculators, using a computer, or using a Standard Normal probability table. The 95% confidence interval for the true binomial population proportion is ( p′ – EBP, p′ + EBP) = (0.810, 0.874).

How do you construct a confidence interval?

There are four steps to constructing a confidence interval.

  1. Identify a sample statistic. Choose the statistic (e.g, sample mean, sample proportion) that you will use to estimate a population parameter.
  2. Select a confidence level.
  3. Find the margin of error.
  4. Specify the confidence interval.

What are the three conditions for constructing a confidence interval for estimating a population proportion?

There are three conditions we need to satisfy before we make a one-sample z-interval to estimate a population proportion. We need to satisfy the random, normal, and independence conditions for these confidence intervals to be valid.

How do you find the population proportion?

Formula Review p′ = x / n where x represents the number of successes and n represents the sample size. The variable p′ is the sample proportion and serves as the point estimate for the true population proportion.

What is the formula for calculating a confidence interval for a population proportion?

To use the standard error, we replace the unknown parameter p with the statistic p̂. The result is the following formula for a confidence interval for a population proportion: p̂ +/- z* (p̂(1 – p̂)/n)0.5.

When a confidence interval for a population mean is constructed from sample data we can conclude?

we can conclude that the population mean is not in the interval B. we can conclude, for an infinite number of samples and corresponding confidence intervals, that the population mean is in a stated percentage of the intervals C.

How do you construct a 95 confidence interval for the population mean?

  1. Because you want a 95 percent confidence interval, your z*-value is 1.96.
  2. Suppose you take a random sample of 100 fingerlings and determine that the average length is 7.5 inches; assume the population standard deviation is 2.3 inches.
  3. Multiply 1.96 times 2.3 divided by the square root of 100 (which is 10).

How large a random sample is needed to construct a 95 percent confidence interval for the mean of this population with a margin of error equal to 1?

Therefore, 385 random samples is needed to construct 95% confidence interval for the mean of the population with a margin of error equal to 1.

How do you find the confidence interval for a proportion?

To calculate the confidence interval, we must find p′, q′. p′ = 0.842 is the sample proportion; this is the point estimate of the population proportion. Since the requested confidence level is CL = 0.95, then α = 1 – CL = 1 – 0.95 = 0.05 ( α 2 ) ( α 2 ) = 0.025.

What Z value is used to construct a 98% confidence interval for the population mean when the population standard deviation is known quizlet?

4. The z score corresponding to a 98 percent confidence level is 1.96. x =z_α/2*σ/n , where σis the population standard deviation and n is the sample size.