A business student is interested in estimating the 95% confidence interval for the proportion of students who bring laptops to campus. He wishes a precise estimate and is willing to draw a large sample that will keep the sample proportion within eight percentage points of the population proportion. What is the minimum sample size required by this student, given that no prior estimate of the population proportion is avallable? (You may find It useful to reference the z table. Round Intermediate calculations to at least 4 decimal places and " value to 3 decimal places. Round up your answer to the nearest whole number.) Minimum sample size

00 00 0 Chalkduster 07+lab+110 15 lılı @27% Part 2. Estimating Population Parameters 3. In a Harris poll of 2036 adults, 40% said that they prefer to get their news online. Construct a 95% confidence interval estimate of the percentage of adults who say that they prefer to get their news online. Can we safely say that fewer than 50% of adults prefer to get their news online? 4. The LA times printed the headline "Most California Voters Support Legalizing Recreational Marijuana." That headline was based on a survey of 1879 Californians, with 1090 of them supporting Proposition 64 (which passed during the November 2016 election and opened up the state for legal cannabis sales starting in 2018). Use the survey results to construct a 95% confidence interval estimate for the percentage of Californians who support legalization of recreational marijuana. Is the claim in the headline supported by the poll findings? X

You need to compute the a 90% confidence interval for the population mean. How large a sample should you draw to ensure that the sample mean does not deviate from the population mean by more than 1.5? (Use 9.2 as an estimate of the population standard deviation from prior studies.) (You may find it useful to reference the z table. Round intermediate calculations to at least 4 decimal places. Round "z" value to 3 decimal places. Round up your answer to the nearest whole number.) Sample size

a researcher wishes to develop an interval estimate for response scores on user surveys. She's not sure about the standard deviation, but in previous years the scores have ranged from 25 to 86. How large a sample should she draw if she wants to construct a 95% confidence interval level that will be within 3 points of the population mean score?

Suppose that you wanted to know if the percentage of people who will attend a sporting event this year will decrease. Last year, 43% of Americans attended a sporting event. After taking a sample, you attain a sample percentage of 18% with a margin of error of 3%. Construct a confidence interval and use that interval to determine if the number of Americans who will attend a sporting event has decreased. Show your calculation for the interval and then state your conclusion in complete sentences.

If you are given summary statistics for a sample and want to construct a confidence interval, this can be done through the Probability Calculator in Geogebra, or Stat>Basic Stats>1-sample Z in Minitab(web). For Minitab (web), see Tutorials in D2L. For Geogebra, follow the directions below: Open it and click the "Statistics" tab just above the graph. For a confidence interval for a population mean, with unknown o, click the drop-down menu near the top (default is "Z Test of a Mean") and choose "T Estimate of a Mean." Enter the confidence level (in decimal form), sample mean, sample standard deviation, and sample size. We'll use a sample with = 65.17, s = 3.654, n = 26. Based on this sample data, a 95% confidence interval for the population mean is: <μ< The margin of error for this 95% confidence interval is Based on this sample data, a 99% confidence interval for the population mean is: <μ< The margin of error for this 99% confidence interval is -

Ellie and Alec are each attempting to estimate the proportion of coffee drinkers who consume more than one cup of coffee per day. They each obtain a random sample of coffee drinkers, and, in each sample, the proportion who drink more than one cup of coffee per day is 0.40. Ellie and Alec each use their sample data to construct a confidence interval. Ellie’s interval is from 0.286 to 0.514, and Alec’s interval is from 0.346 to 0.474. One of these intervals was computed correctly, but the other was not. Which interval must be incorrect? A. Ellie’s interval must be incorrect. B. Alec’s interval must be incorrect. C. It’s impossible to answer this question without knowing the level of confidence used for each interval. D. It’s impossible to answer this question without knowing the sample sizes. E. It’s impossible to answer this question without knowing the sample sizes or the level of confidence used for each interval.

You would like to construct a 99% confidence interval to estimate today's population mean temperature, so you make a series of measurements (a random sample) throughout the day. The mean of these measurements is 58.5 degrees Fahrenheit, and their standard deviation is 3.0 degrees Fahrenheit. For each of the following sampling scenarios, determine which distribution should be used to calculate the critical value for the 99% confidence interval for the population mean.(In the table, Z refers to a standard normal distribution, and t refers to a t distribution.)