Which test is used to find Population mean/median when the form of population is not known and sample size is small? and  Population mean when the form of population is not known and sample size is large???  Which non-perametric test is best for these tests? ... View more

If the magnitude of the earthquakes recorded in a region of a country follows an exponential distribution with parameter θ, show that obtained estimator is also sufficient estimator using invariance property of sufficiency. ... View more

In 90% confidence interval for 12 number of degrees of freedom , using Chi-square_(0.90)=5.226 and Chi-square_(0.05)=21.026 while in 95% confidence interval for 19 number of degrees of freedom we using Chi-suqare_(0.975)=8.907 and Chi-square_(0.025)=32.852.  How can selcet a Chi-square interval for given number of degrees of freedom of a confidence level? Hope question is understandable.   ... View more

In a state with a total population of 70,000 adults, 34, 000 are males and out of a total of 5000 graduates, 700 are females. Out of 1200 graduate employees of the state 200 are females. Is there any sex bias in education among people? The state holds that no distribution is made in appointments with respect of sex. How far this claim is substantiated by the data given above? ... View more

An ambulance agency claims that the standard deviation of the length of service times is 5 minutes. Investigator suspects that this claim is wrong. She takes a random sample of 20 services and finds the standard deviation as 6 minutes. Assume that the service time of the ambulance follows normal distribution. i) What is the probability that the standard deviation of the length of service times is more than and equal to 5 minutes. ii) Find the 95% confidence interval for the standard deviation of the length of service times. iii) Test, at  = 0.01, is there enough evidence to reject the agency’s claim? ... View more

For testing the pulse rate of one month old child is to be 120 per minute, a researcher measures (per minute) the pulse rate of 10 one month old children as 120,118,125,122,117,120,121, 126,125,115 and applies sign test and Wilcoxon signedrank test, then power of the Wilcoxon signed-rank test is more than the sign test. True or False!?   ... View more