Week 6 Assignment: Confidence Intervals for Population Propor- tion Calculate the Mean and Standard Deviation of...
Confidence Intervals: A group of 50 randomly selected JWU students have a mean age of 20.5 years. Assume the population standard deviation is 1.5 years. Construct a 99% confidence interval for the JWU population mean age. State your answer. (Zc 2.57) 1. 2. Construct a 90% confidence interval for the population mean, . Assume the population has a 2 normal distribution. A random sample of 20 JWU college students has mean annual earnings of 0 $3310 with a standard deviation...
Week 6 Assignment: Confidence Interval for Population Mean- Population Standard Deviation Known Question supplement bottle is 16 pills. If we want to be 95 % confident The population standard deviation for the number of pills that the sample mean is within 5 pills of the true population mean, what is the minimum sample size that should be taken? in a Zo,01 Z0,005 Zo.10 Zo.05 Zo025 2.576 2.326 1.645 1.960 1.282 Use the table above for the z-score, and be sure...
3) Find the indicated confidence interval. Assume the standard error comes from a bootstrap distribution that is approximately normally distributed. A 95% confidence interval for a difference in means μ1-μ2 if the samples have n1=80 with x¯1=269 and s1=48and n2=120 with x¯2=229 and s2=49, and the standard error is SE=6.99. Round your answers to three decimal places. The 95% confidence interval is ______________ to ____________ ______________________________________________________________________ 5) How Much More Effective Is It to Test Yourself in Studying? We have...
Question 2 Based on the 1988 National Survey of Families and Households, it was re- ported that men spent a mean of 18.1 hours per week doing housework. Suppose the standard deviation was 13.1 hours a normal distribution, sketch the approximat a Assuming e distribution of the number of hours that a randomly selected man spent doing housework in 1988 b Based on the graph in part (a), explain why the population distribution is very unlikely to be normal and...
Question 2 Based on the 1988 National Survey of Families and Households, it was re- ported that men spent a mean of 18.1 hours per week doing housework. Suppose the standard deviation was 13.1 hours. a Assuming a normal distribution, sketch the approximate distribution of the number of hours that a randomly selected man spent doing housework in 1988 b Based on the graph in part (a), explain why the population distribution is very unlikely to be normal and why...
This problem demonstrates how to calculate the confidence interval for a population proportion. After, you will be asked to redo the calculations (with small variations). A survey was conducted to determine how many people were in favor of a proposed law to criminalize texting while driving. Response options included strongly disagree, disagree, neither agree or disagree, agree, and strongly agree. The survey asked a random sample of 800 18- to 25-year-olds, and 648 indicated agreeing or strongly agreeing with the...
2010 Week 6 Assignment: Confidence Interval for Mean - Population Stan- dard Deviation Known Home Sylabus Announcements Question Resources Modules The heights of dogs in inches, in a city are normally distributed with a population standard devion of 4 inches and an unknown population mean, If a random sample of 18 does is taken and results in a sample mean of 32 inches, find the error bound (BM) of the confidence interval with a 90% confidence level 1.282 1645 1.960...
Use standard normal and t-Distribution tablesYou are expected to use the Standard Normal and the t-Distribution Tables for all answers on this quiz. You must algebraically calculate the Margin or Error by hand for problems requiring that. Calculator-produced probabilities or confidence intervals will receive minimal credit. 1. (1.5 points) A survey of 177 fatal accidents showed that, in 42 cases, the driver at fault was inadequately insured. Find a point estimate for the population proportion, p, of accidents where the...
Assume the grades has Normal distribution with the mean of 70, and the standard deviation of 15. Answer the following questions 1. Calculate 10t 25t* 50 75t and 90* percentiles once by converting to the standard Normal distribution, and again directly (using the non-standard Normal distribution) 2. What percentage of students score between 80 and 90 in the exam? 3. What percentage of students fail? 4. What percentage of students pass with A? 5. Generate a sample of size 16...
Research question: In the population of all American adults, how strong is the relationship between age and reaction time? Data were collected from a representative sample of 500 American adults concerning their ages (in years) and reaction times (in milliseconds). What procedure should be used to estimate the strength of this relationship in the population? CI for single mean CI for single proportion CI for difference in means CI for difference in proportions CI for correlation 2Research question: To what...