Video Buzz | z-test Streaming Video You Should be Watching

July 3rd

Compare proportions from two samples of same population: Comparing Proportions From Two Independent Samples (Z-test) Used to compare two proportions created by two random samples or two subgroups of one random sample. eg: A survey was conducted of students from the Princeton public school system to determine if the incidence of hungry children was consistent in two schools located in lower-income areas. A random sample of 80 elementary students from school A found that 23% did not have breakfast before coming to school. A random sample of 180 elementary students from school B found that 7% did not have breakfast before coming to school.
Compare Sample Proportion to a Population: eg: Historical data indicates that about 10% of your agency's clients believe they were given poor service. Now under new management for six months, a random sample of 150 clients found that 15% believe they were given poor service.

June 9th