Please help me with this. Wha is the difference between all these definitions and there place in the hypothesis t-test z-test t-statistic test-statistic z-statistic f-test chi-square test. I can calculate, but why so many phrase, do they over lap?? UHG!!! Thanks for the help
yep, been there…pulled out my hair already so I’ll try to help - test statistic: these are the calculated values that are then compared to critical values. We can use ‘z’ or ‘t’ statistics depending on sample size, known pop. mean. z-statistic & t-statistic are two kinds of test statistics. calc are pretty much the same - use pop std. dev for z and sample std. dev for t (since pop std. dev is unknown in this case). check out the t-statistic vs. z-statistic chart to see when to use which (there are also some concept questions around this info so it’s a must-know). The critical values are the table values based on significance level, df’s, etc. if test values lie outside the critical value area then reject Ho. For my sanity’s sake I’m choosing to ignore f-test and chi-square test except for the following facts: use f-test to test equality of variances of two populations use chi-square test for variance of single population - both of these distributions are bound by zero on the left and are asymmetrical. hope I helped even a small bit. HATE this.
It is late and you have helped. Thanks I will keep note of this thread for reference