STILL MORE 9.1. VI. CORRELATION & CAUSATION Just because there is a strong relationship, this does NOT imply cause and effect!

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Presentation transcript:

STILL MORE 9.1

VI. CORRELATION & CAUSATION Just because there is a strong relationship, this does NOT imply cause and effect!

A RESEARCHER MUST CONSIDER THE FOLLOWING POSSIBILITIES: 1.Is there a direct cause and effect relationship between the variables? 2.Is there a reverse cause and effect relationship between the variables? 3.Is it possible the relationship is caused by a 3 rd variable or combination of variables? 4.Is it possible the relationship is a coincidence?

V. HYPOTHESIS TESTING FOR A POPULATION CORRELATION COEFFICIENT

BACK TO 5 STEP HYPOTHESIS TESTING! WOOHOO! 1.State hypotheses 2.Find test statistic 3.Find critical value 4.Make a decision 5.Interpret in context

NOW DO PG 472 #23 WITH 5 STEPS! 1) 2) 3) 4) 5)

CLASS WORK TO BE TURNED IN!!! Pg 473 #27 (show all 5 steps) HOMEWORK: Pg 473 #28