week 13 reveiw

week 13 reveiw Order Description Statistics Exam Practice Questions 2015 1.    different types of graphs 2.    box plots 3.    the different types of statistical tests 4.    how to distinguish between dependent and independent variables 5.    What does sampling actually mean (sampling theory)? 6.    What is the difference between "population" and "sample"? (Answered) Population is the population is ‘all of the people we are interested in’, but populations are not necessarily people it could be all of a high school, all people on a bus and Sample is the amount (metric) 7.    What is the formula for calculating Z-Scores? What are they used for? (Answered) The formula for a Z-score is  , where X is the observation value,  is the population mean and  is the population standard deviation. It is used to determine if the observation is "expected" or not, assuming it comes from the same population as  . If the value of Z is less than or greater than 2, this means that the value of X is more than 2 standard deviations away from the population mean, and there "unusual". Z=x-u divided by o