Stats Test 2 Prep

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Stats Test 2 Prep
2011-03-18 02:12:27
Stat test prep

Stat 1100Q preparation for test 2
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  1. Situation in which the outcome is unknown before
    it happens...give example
    • Random Experiment
    • rolling die
  2. This is the most basic outcome of a random experiment
    (simple event)..give example
    • Sample Point
    • head or tail for a coin toss
  3. This is a collection of sample points
  4. This is a collection of all sample points in the experiment
    Sample space
  5. The probability of an event (or simple event) is simply what you think it is , so long as the values of probability are observed...give example
    • Personal probability
    • flipping a coin and peaking
  6. The probability of a (simple) event happening is
    the “long-run” relative frequency of that event
    Relative frequency interpretation
  7. In the event that both A and B occur at the same time it is called an...
  8. The probability of either A or B happening is called a ?
  9. Give the 2 terms assigned for when two events CANNOT happen at the same time
    • Mutually exclusive
    • disjoint
  10. What is the formula for (A u B)
    P(A)+P(B)-P(A n B)
  11. What is the formula for (A u B) if A and B are mutually exclusive..explain
    • P(A)+P(B)-P(A n B)=P(A)+P(B)
    • this is because A n B can't happen together
  12. What is the formula for conditional probability? (A|B)
    P(A n B)/P(B)
  13. In the formula for A|B can you calculate A n B directly?
    No, it must be either given or extrapolated from a different formula
  14. If knowledge of one event happening does not change the probability of the other one happening, the two events are said to be...
  15. What does this mean: A u B u C...
    probability of at least one of these events have happening
  16. What does this notation mean: A n B n C..
    These events have all happened
  17. What does this mean: A u B n C
    Nothing..has no meaning...must know which one to do first
  18. What does this notation mean: (A u B) n C
    First the probability of the union of event A and B then the probability of the intersection of one of those with C
  19. Based on the distributive rule, what does this equal: A u (B n C)
    (A u B) n (A u C)
  20. Based on the distributive rule, what does this equal: A n (B u C)
    (A n B) u (A n C)
  21. This is a sample that represents our population well
    Representative sample
  22. If a sample is not representative of the entire population, it is called:
  23. What are the 3 types of sample bias?
    • Response bias
    • Non-response bias
    • Sampling bias
  24. What is a response bias..give example
    • Measurement obtained that is incorrect
    • lies in a survey
    • bad scale
  25. What is a non-response bias?..give example
    • Simply getting no response at all
    • anything involving volunteer answers
    • scale you can't use
  26. What is Selection bias?...give example
    • Taking a sample that is not from your general population
    • Wanting a survey of the UConn population but only surveying grad students
  27. How do you control sample bias
    by taking simple random samples
  28. A list of everything in your population is called a...
    population frame
  29. What is a convenience sample, and would it be a good representation?
    • Simply sampling those around you at the time
    • bad representation
  30. What is cluster sampling?...and is it a good representation
    • Breaking the population into groups and taking simple random samples of each group
    • good representation
  31. What is stratified sampling and how good of a representation is it?
    • Breaking the population into different groups which have members with similar properties then doing SRS
    • very good representation
  32. This type of random variable can on a particular value
    Discrete random variable
  33. This type of random variable can take on any value in one or more intervals
    Continuous random variable