Question

Question 4: A study collected data for 1000 individuals in United States. This data indicates U.S. has an average life expectancy of 78.74 years with a standard deviation of 8.9 years. You would like to determine whether the U.S. has a life expectancy greater than the worldwide average, which is 71.5 years. Use this information and answer questions 4a to 4g. Question 4a: Define J p-the life expectancy of the U.S. population ?-the life expectancy of the worldwide population the life expectancy of the 1000 individuals measured from the U.S. population Question 4b What is your null and alternative hypothesis test? Ho : ?-7874 111 ; ? > 78.74 Ho : ? = 71.5 H1 : ? > 71.5 Ho : ?-71.5 H1 : ??71.5 Ho : ? = 78.74 H, ; ? 78.74 H1 : ? < 71.5 Ho78.74 H, ; ? < 78.74 Question 4c Determine the value of the test statistic. (Use 3 decimal places) Question 4d What would you conclude when a significance level of 0.05 is used? There is not enoueh information to conclude. O Reject H ? Accept Hu O Do not reject Ho- Question 4e How to interpret the hypothesis test conclusion when a significance level of 0.05 is used? O There is not enough statistical evidence show that the U.S. population has a life expectancy greater than the worldwide life expectancy at a 0.05 level of significance. O There is strong statistical evidence to sueeest that the U.S. population has a life expectancy greater than the worldwide life expectancy at a 0.05 level of significance The U.S. population has a life expectancy greater than the worldwide life expectancy at a 0.05 level of The U.5. population has a life expectancy the same as the worldwide life expectancy at a 0.05 level of significance

Answer 1

Answer Date: 17/04/2018 a) is population mean life expectancy of the worldwide population. b) To test the hypothesis is that the mean life expectancy is higher than 71.50 years at 5% significance level The null and alternative hypothesis is, H0:μ=71.50 Ha 71.50 c) The t-test statistics is,

孓ー山) 78.74-71.50 8.90/1000 25.725 The t-test statistics is 25.725. The t-critical value is, The sample size is small and right-tailed test. Look in the column headed α = 0.05 the row headed in the t distribution table by using degree of freedom is, and d,f.= n-1 1000 1 - 999 The t-critical value is 1.962 d)

Decision The statistical decision is that the t-test statistics which is 25.725 is higher than t-critical value which is 1 .962, so the null hypothesis is rejected at 5% level of significance. e) There is sufficient evidence to indicate that the mean life expectancy is higher than 71.50 years. The result is statistically significant