Notes on Biostat Exam 2 

  1. We have done our best to create a fair, consistent, and accurate answer key. We look carefully at each response. This takes many hours, but I feel this is are primary from of communication, given the large n of the class. I hope you will review your exams carefully.  This is a good learning opportunity.  
  2. I believe the value of a college education is in its encouragement of higher levels of thinking. Can we speak of a moral obligation to be intelligent? I think so, and I believe you are all capable of developing your scholarship. The requires commitment. It also requires more than a mechanical or formulaic approach. This is why I spend some time setting up questions and establishing terminology before setting upon answers. 
    Beware the quick answer which is 
    the right answer to the wrong question.
  3. I will describe in lecture a good example of the Law of the Farm I observed in a couple of students. 
  4. What I expect from each of you:
    1. Attendance (lectures & labs)
    2. Attentiveness
    3. Diligence 
    4. Labs completed before HW completed 
    5. HW completed before the last minute
  5. Indicators of poor performance - and what to do about it
    1. Missing points on Lab Workbook - physical presence in lab; diligence; start lab early
    2. Missing more than 4 point on short answer exams - attentiveness to definitions and concepts, memorization of definitions, focus on concepts
    3. Missing more than 7 points on open ended exams - better Procedure notebook preparation; stress-reduction; more practice of HW exercises
  6. Your first awareness of an issue will to a large extent determine the quality of thought thereafter. Make small and fine distinctions at inception. Avoid jumping to the answer too quickly. Understand the context before seeking solutions. Analyze context carefully.
    1. Example 1: Question 1 in Part B asked about the sampling distribution of means from your classmates (lab 5). It did not ask about your sample mean as such. Many students proceeded to tell me about their data, which was irrelevant.
    2. Example 2: What does the phrase "sigma known" really mean? Some students still think that if a problem provides the standard deviation, then sigma is known. They fail to make the distinction that if the standard deviation was calculated from a data set, sigma is not known. (By definition, any standard deviation that comes from a sample is not sigma.)
  7. Strong correlation between HW diligence and test performance (r = 0.67, p < .0005)
  8. Results were STRONG, with a median of 89