Video Tutorial – Allelic Frequencies Remain Constant From Generation to Generation Under the Hardy-Weinberg Equilibrium

The Hardy-Weinberg law is a fundamental principle in statistical genetics.  If its 7 assumptions are fulfilled, then it predicts that the allelic frequency of a genetic trait will remain constant from generation to generation.  In this new video tutorial in my Youtube channel, I explain the math behind the Hardy-Weinberg theorem.  In particular, I clarify the origin of the connection between allelic frequencies and genotyopic frequencies in the second generation – I have not found a single textbook or web site on this topic that explains this calculation, so I hope that my explanation is helpful to you.


Presentation on Statistical Genetics at Vancouver SAS User Group – Wednesday, May 28, 2014

I am excited and delighted to be invited to present at the Vancouver SAS User Group‘s next meeting.  I will provide an introduction to statistical genetics; specifically, I will

  • define basic terminology in genetics
  • explain the Hardy-Weinberg equilibrium in detail
  • illustrate how Pearson’s chi-squared goodness-of-fit test can be used in PROC FREQ in SAS to check the Hardy-Weinberg equilibrium
  • illustrate how the Newton-Raphson algorithm can be used for maximum likelihood estimation in PROC IML in SAS

Eric Cai - Official Head Shot








You can register for this meeting here.  The meeting’s coordinates are

9:00am – 3:00pm

Wednesday, May 28th, 2014

BC Cancer Agency Research Centre

675 West 10th Avenue.

Vancouver, BC


If you will attend this meeting, please feel free to come up and say “Hello!”.  I look forward to meeting you!

A New Job at the British Columbia Centre for Excellence in HIV/AIDS

Dear Readers of The Chemical Statistician,

You may have noticed that I have blogged less frequently in the past few months; this has been due to a major change in my career: I recently accepted a new job in the Laboratory Program at the British Columbia Centre for Excellence (BC-CFE) in HIV/AIDS in Vancouver!

Eric Cai - Official Head Shot

A bioinformatician who works in this group recommended me for this position to his supervisors during this past summer.  Having lived in Vancouver before, I have heard a lot about the work that the BC-CFE in HIV/AIDS has done for many years to improve the lives of HIV and AIDS patients and prevent HIV transmission.

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