--%>
Assignment Help - homework help

State the hypotheses

At Western University the historical mean of scholarship examination score for freshman applications is 900. Population standard deviation is assumed to be known as 180. Each year, the assistant dean uses a sample of applications to determine whether the mean examination score for the new freshman applications has changed.

a) State the hypotheses.

b) What is the 95% confidence interval estimate of the population mean examination score if a

sample of 100 applications provided a sample mean 935?

c) Use the confidence interval approach to conduct a hypothesis test. What is your conclusion?

d) Assuming α = .05, conduct p-value based and critical-value based hypothesis tests. How do the results compare in all the three cases?

 

E

Expert

Verified

(a)

Null Hypothesis H0: µ =900

Alternative Hypothesis H1: µ ≠ 900

(b)

C.I for mean = [X-bar - Z*SD/  < µ < X-bar + Z*SD/  ]

                       = [935 - 1.96*180/10 < µ < 935 + 1.96*180/10]

                       = [899.72, 970.28]

(c)

900 is just within the interval at lower end, so we can't reject null hypothesis.

(d)

Z-statistic = (935-900)/180/

                   = 1.94

1.94 is neither greater than 1.96 nor smaller than -1.96 so we can not reject null hypothesis. P-value will be slightly greater than level of significance α.

 

   Related Questions in Basic Statistics

  • Q : Compare the test results The grade

    The grade point averages of 61 students who completed a college course in financial accounting have a standard deviation of .790. The grade point averages of 17 students who dropped out of the same course have a standard deviation of .940. Do the data indicate a

    		•
  • Q : Networks of queues Networks of queues •

    Networks of queues • Typically, the flow of customers/request through a system may involve a number of different processing nodes.– IP packets through a computer network– Orders through a manufactur

    		•
  • Q : Sample z test and Sample t test A

    A random sample X1, X2, …, Xn is from a normal population with mean µ and variance σ2. If σ is unknown, give a 95% confidence interval of the population mean, and interpret it. Discuss the major diff

    		•
  • Q : Time series what are the four

    what are the four components of time series?

    		•
  • Q : OIL I need to product when oil will

    I need to product when oil will finish time (by years) for 6 countries if the keep their production (per day) in the same level. So, the 6 countries have fixed reserves and production 1. statistics for Bahrain Crude oil reserves (million barrels) = 124.6 be careful in million Crude oil producti

    		•
  • Q : Define Service Demand Law

    Service Demand Law:• Dk = SKVK, Average time spent by a typical request obtaining service from resource k• DK = (ρk/X

    		•
  • Q : Average think time Software monitor

    Software monitor data for an interactive system shows a CPU utilization of 75%, a 3 second CPU service demand, a response time of 15 seconds, and 10 active users. Determine the average think time of these users?

    		•
  • Q : Data Description 1. If the mean number

    1. If the mean number of hours of television watched by teenagers per week is 12 with a standard deviation of 2 hours, what proportion of teenagers watch 16 to 18 hours of TV a week? (Assume a normal distribution.) A. 2.1% B. 4.5% C. 0.3% D. 4.2% 2. The probability of an offender having a s

    		•
  • Q : Define Utilization Law Utilization Law

    Utilization Law: • ρk = XK . SK = X . DK • Utilization of a resource is the fraction

    		•
  • Q : Building Models Building Models • What

    Building Models • What do we need to know to build a model?– For model checking we need to specify behavior • Consider a simple vending machine – A custome rinserts coins, selects a beverage and receives a can of soda &bul

    		•