Online T Test Tutors

Online T Test Tutors Definition:-Many times the size of the sample that is used to make a test of hypothesis about population mean is small that is (n30), when population standard deviation is unknown, if the population is normally distributed then the appropriate distribution is t test. This may be the case because we have limited resources and cannot afford to take a large sample or because of nature of the experiment itself. For example:- To test a new car model of a car for fuel efficiency (miles per gallon), the company may prefer to use a small sample, All cars included in such a test must be sold as used cars. In the case of a small sample, if the population from which the sample is drawn is (approximately) normally distributed and the population standard deviation is known, we can still use the normal distribution to make the test of hypothesis about population mean . However if the population is (approximately) normally distributed, the population standard deviation is not known, and the sample size is small (n 30), then the normal distribution is replaced by the t test. Condition under which the t distribution is used to make test of hypothesis about : The t test is used to conduct a test of hypothesis about if The sample size is small (n30) The population from which sample is drawn is approximately normally distributed. The population standard deviation is unknown. Test statistic:- The value of the test statistic t for the sample mean x? is computed as t= (x?- )/ (s/n) Where s= sample standard deviation.