Confidence intervals and levels of significance

Assignment Help Basic Statistics
Reference no: EM13106069

In a statistics lecture, students are asked whether or not they enjoyed doing statistics. Random sample of 50 students was taken and 30 of them said that they enjoyed doing statistics. The lecturer claimed that more than 50% of the students enjoyed doing statistics.

(i) Test, at the 5% level of significance, whether or not the lecturer's claim is reasonable. State the null and alternative hypotheses of the test.

(ii) Find a 95% and a 99% confidence intervals for the true proportion of students who enjoyed doing statistics. Which one is wider? Why?

(iii) If the lecturer would like the difference between the true proportion and the sample
proportion to be less than 5%, what is the minimum number of students he should ask Use alpha = 0.05

Reference no: EM13106069

Questions Cloud

What is the magnitude of the initial velocity : A projectile is red from level ground at an angle of 30 degree above the horizon. It hits the ground at t = 4 s. What is the magnitude of the initial velocity, v?
Confidence intervals and standard deviation : In a manufacturing process, the diameter of the steel rods is the product characteristic. A random sample of 25 steel rods is taken and sample mean is 8.88 cm.
Importance of collecting information about competitors : Discuss the importance of collecting information about competitors? Distinguish between ethical and unethical methods of gathering competitive intelligence.
How much energy will be stored in the capacitor : A parallel-plate capacitor is made from two plates 12.5 cm on each side and 4.20 mm apart. Half of the space between these plates contains only air, but the other half is filled with Plexiglas of dielectric constant 3.40.
Confidence intervals and levels of significance : In a statistics lecture, students are asked whether or not they enjoyed doing statistics. Random sample of 50 students was taken and 30 of them said that they enjoyed doing statistics.
Detailed explanation of confidence intervals : You are given the sample mean and the sample standard deviation. use this information to construct the 90% and 95% confidence intervals for the population mean.
Describe an approach to business diversity program : Describe an approach to a business diversity program that would be pragmatic and ethical. he definition of diversity rests on a valuation of differences across different groups.
Explain brand which uses multiple media sources : Choose a brand which uses multiple media sources. What do you like/dislike about marketing message? Does their message appear consistent throughout different media sources used?
Mean score confidence interval : A nursing professional conducts an analysis to examine scores on the mental health service and treatment outcome questionnaire.

Reviews

Write a Review

Basic Statistics Questions & Answers

  Describing name of parts of regression equation

Write down the name of 4 parts of the regression equation.

  Probabilities and expected values

Sarah is a 60 year old Anglo female in reasonably good health. She wants to take out a $50,000 term life insurance policy until she is 65.

  Homogeneity of variance assumption

For each of the following problems, assume that the homogeneity of variance assumption has not been met and that you will need to use the adjusted Welch statistic.

  Determining sample proportion

Suppose that 15% of all adults jog. An opinion poll asks a simple random sample of 500 adults if they jog. What is the sampling proportion in the sample who jog?

  Determining health maintenance services

An auditor for a Health Maintenance service of Georgia reports 40% of policyholder 55 years or older submit a claim during the year. Fifteen policyholders are randomly selected for company records.

  Probability of observing an event

Two airlines fly to Memphis. according to airport data for the past year, wings airlines planes arrived on time 330 times and were late 60 times. Global airlines planes arrived on time 430 times and were late 50 times.

  Show the steps in hypothesis test procedure

Steps in hypothesis test procedure - conducting a hypothesis test for some general statistic, ? say.

  Formulating the hypotheses for a given problem

The average age of the students in the sample was 23 with a standard deviation of 3.5: a) Formulate the hypotheses for this problem.

  Chebyshev inequality

Household income does not tend to follow a normal distribution in a particular state, yet average income is approximately $45,000/year in this state, with a standard deviation of about $9000.

  Probability for student with master-s degree in english

Compute the probability that randomly chosen student with a Master's degree majored in English or mathematics?

  Purpose of developing frequency distribution

Critically discuss the purpose of developing a frequency distribution? What is the relationship between the relative frequency and the cumulative frequency? Could a frequency distribution contain qualitative data? Why?

  Determining confidence interval for the mean number

Find a 98% confidence interval for the mean number of days required for successful completion of physical therapy for patients in the average group. Discuss the results.

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd