A standardized IQ test is known to be normally distributed and has μ=100 and σ=10. there is a common belief that students in wealthier school districts tend to have higher IQ scores. A researcher randomly selects a sample of 25 students from wealthy school districts. The average IQ of the sample is x̅=103. Conduct a test if the average score for students from wealthy districts is higher than 100, assuming α=0.05

A standardized IQ test is known to be normally distributed and has μ=100 and σ=10. there is a common belief that students in wealthier school districts tend to have higher IQ scores. A researcher randomly selects a sample of 25 students from wealthy school districts. The average IQ of the sample is x̅=103. Conduct a test if the average score for students from wealthy districts is higher than 100, assuming α=0.05

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.1: Measures Of Center

Problem 9PPS

See similar textbooks

Similar questions

If X1 and X2 constitute a random sample of size n = 2from an exponential population, find the efficiency of 2Y1relative to X, where Y1 is the first order statistic and 2Y1and X are both unbiased estimators of the parameter
Suppose a linear model y=β0+β1xy=β0+β1x is fit to a sample data set, and a test of the null hypothesis H0:β1=0H0:β1=0 against an alternative hypothesis HA:β1≠0HA:β1≠0 is performed; a PP-value of 0.4203 is obtained. Which of the following scatter plots depicts the data set on which this model was fit and the hypothesis test was performed?
A snack food manufacturer estimates that the variance of the number of grams of carbohydrates in servings of its tortilla chips is 1.33. A dietician is asked to test this claim and finds that a random sample of 24 servings has a variance of 1.37. At α=0.01, is there enough evidence to reject the manufacturer's claim? Assume the population is normally distributed. Complete parts (a) through (e) below. (a) Write the claim mathematically and identify H0 and Ha. A. H0: σ2≤1.33 (Claim) Ha: σ2>1.33 B. H0: σ2≠1.33 Ha: σ2=1.33 (Claim) C. H0: σ2≥1.33 Ha: σ2<1.33 (Claim) D. H0: σ2=1.33 (Claim) Ha: σ2≠1.33 (b) Find the critical value(s) and identify the rejection region(s). The critical value(s) is(are) enter your response here. (Round to two decimal places as needed. Use a comma to separate answers as needed.) Choose the correct statement below and fill in the corresponding answer boxes. A. The…
If our significant value falls below alpha, which is set at .05, we are over 95% confident that the results did not happen by chance. true or false?
Let X1, ..., Xn be a sample from an exponential population with parameter λ.(a) Find the maximum likelihood estimator for λ. (b) Is the estimator unbiased?(c) Is the estimator consistent?
A simple random sample of size 200 is taken from a much larger group of male wrestlers prior to a competition. The average weight in the sample is 190 pounds, with an SD of 20 pounds. The average weight of the population is estimated to be 190 pounds, and this estimate is likely to be off by about _______.
A fisheries biologist collected a random sample of fish from a lake and conducted a chi-square goodness-of-fit test to see if the distribution of fish changed over time. The table below shows the distribution of fish that were put into the lake when it was originally stocked. Fish Type Trout Bass Perch Sunfish Catfish Percent 25% 25% 20% 15% 15% The biologist found evidence to reject the null hypothesis in favor of the alternative hypothesis. Which of the following represents the alternative hypothesis of the test?
The germination rate of seeds is defined as the proportion of seeds that, when properly planted and watered, sprout and grow. A certain variety of grass seed usually has a germination rate of 0.80, and a company wants to see if spraying the seeds with a chemical that is known to change germination rates in other species will change the germination rate of this grass species. (a) Suppose the company plans to spray a random sample of 400 seeds and conduct a two-sided test of 0: 0.8Hpusing = 0.05. They determine that the power of this test against the alternative 0.75pis 0.69. Interpret the power of this test.(b) Describe two ways the company can increase the power of the test. What is a disadvantage of each of these ways? (c) The company researchers spray 400 seeds with the chemical and 307 of the seeds germinate. This produces a 95% confidence interval for the proportion of seeds that germinate of (0.726, 0.809). Use this confidence interval to determine whether the test described in…
b) Find the critical value of t for a 90% confidence interval with df=58.
Suppose X1,...,Xn are iid with PDF f(x | θ) = 2x/θ2, 0 < x < θ. (a) Write out the joint PDF f(x | θ), and write the likelihood function L(θ | x). (b) Find the MLE for θ. (c) Find the MLE for the median of the distribution.
If X follows a binomial distribution with p = 0.1 and n =100, find the approximate value of P(2 ≤ X ≤ 4) using the normal approximation. the Poisson approximation.
A researcher obtains t=2.25 for a repeated measures study using a sample of n=10 participants. Based on this t value, what is the correct decision for a two- tail test at .05 and .01 alpha level?