Biostatistics Exam #3

  1. What are the two types of inferential statistics?
    • 1) Estimation
    • 2) Hypothesis Testing
  2. What are the two types of Estimation?
    • 1) Point Estimation
    • 2) Interval Estimation
  3. What is the difference between the two types of Estimation?
    A point estimate of a population parameter is a single value of a statistic. For example, the sample mean x is a point estimate of the population mean μ. Similarly, the sample proportion p is a point estimate of the population proportion P.

    An interval estimate is defined by two numbers, between which a population parameter is said to lie. For example, a < x < b is an interval estimate of the population mean μ. It indicates that the population mean is greater than a but less than b.
  4. The normal distribution is appropriate if what two conditions are valid?
    • 1) np ≥ 5
    • 2) n(1-p) ≥ 5
  5. What does it mean to fall in the shaded area labeled 95%?Image Upload 1
    The interval estimate of a confidence interval is defined by the sample statistic ± margin of error. For example, we might say that we are 95% confident that the true population mean falls within a specified range. This statement is a confidence interval. It means that if we used the same sampling method to select different samples and compute different interval estimates, the true population mean would fall within a range defined by the sample statistic ± margin of error 95% of the time.
  6. What are the confidence coefficients of the following confidence percentages:

    1) 90%
    2) 95%
    3) 99%
    • 1) ± 1.645
    • 2) ± 1.96
    • 3) ± 2.575
  7. What are the four steps involved in testing hypotheses about population parameters?
    • 1) Statement of the pair of hypothesis to be tested
    • 2) Test statistic (formula)
    • 3) Make a statistical decision
    • 4) Nonstatistical decision
  8. What are the three possible pairs of hypotheses and their corresponding key terms?
    • 1) H0 H0 affect, difference vague
    • 2) H0 > H0 increase, more than, greater, takes directon
    • 3) H0 < H0 decrease, less than, lower, takes direction
Card Set
Biostatistics Exam #3
All information leading up to the third examination for PHCY 4600.