The lecture Contingency Tables by David Spade, PhD is from the course Learn Statistics  Become Data Smart. It contains the following chapters:
What is a contingency table?
What statement below is correct about marginal distributions?
What is correct about conditional distribution?
Which of the following statements is correct?
What is Simpson’s Paradox?
What is another term for a contingency table?
What is true about the marginal frequency of the category corresponding to the row?
Relative frequencies should add up to which of the following?
Percentages we come up with for conditional distributions must add up to which of the following?
How may Simpson's Paradox be present in a contingency table?
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It is better than that I watched in other web site. I really recommend this lecture.
Clear explanations that makes understanding of concepts easy. Relevant examples too