Statistics Quiz 3

Name: _____________________________________

  1. To improve an experiment, we can always
    1. Reduce Type I error to 0
    2. Reduce Type II error to 0
    3. Eliminate some Type I error, but only by increasing Type II error
    4. All of the above
  2. We conduct scientific experiments to measure the heat produced by a chemical reaction. The average reading was 10 calories of heat produced. If the standard deviation was 2 calories, and the measurements are normally distributed...

    What percentage of measurements were less than 10 calories?
    1. 50%
    2. 10%
    3. 20%
    4. 100%
  3. What percentage of measurements were greater than 10 calories?
    1. 50%
    2. 10%
    3. 20%
    4. 100%
  4. What percentage of measurements were between 8 calories and 12 calories?
    1. 16%
    2. 95%
    3. 34%
    4. 68%
  5. What percentage of measurements were less than 6 calories?
    1. 2%
    2. 8%
    3. 16%
    4. 47%
  6. What percentage of measurements were greater than 16 calories?
    1. Less than 10%
    2. Over 50%
    3. Less than 0%
    4. Less than 1%
  7. What percentage of measurements were between 6 and 14 calories?
    1. Less than 1%
    2. About 95%
    3. About 5%
    4. About 50%
  8. If a scientist got a measurement of 2 calories, how should you regard that measurement?
    1. Very suspicious: it is massively unlikely.
    2. Nothing to see here; move along!
    3. It definitely confirms the scientists was faking their results.
    4. Not enough information.
  9. To a mathematician, the definition of probability is:
    1. a personal belief
    2. a real number between 0 and 1
    3. an integer greater than one
    4. a question Tornike will never get right
  10. There are four suits in a deck of cards: hearts, diamonds, spades, and clubs. Each suit has 13 cards. So if you draw 24 cards randomly, you should expect 6 of each suit.

    Here is your actual outcome when Kenneth deals you the cards:
    Suit fo fe
    Hearts 11 6
    Diamonds 2 6
    Spades 3 6
    Clubs 8 6

    In this situation, the null hypothesis should be:
    1. The deal is fair
    2. Kenneth looks like a card shark, so the deal is most likely unfair
    3. Why is the professor picking on Kenneth?
    4. Can't say
    11. Χ2 formula
  11. Using the above data, we get a chi-square score of:
    1. 90
    2. 18
    3. 9
    4. 1
  12. If we had set α at .05, we should:
    1. reject the null hypothesis
    2. fail to reject the null hypothesis
    3. conclude with certainty that Kenneth was cheating
    4. not enough information
  13. If we had set α at .01, we should:
    1. reject the null hypothesis
    2. fail to reject the null hypothesis
    3. conclude with certainty that Kenneth was cheating
    4. not enough information
  14. If we look at the above data for what might be interesting, we should conclude:
    1. why are there only four categories?
    2. all of those sixes look fishy
    3. too many clubs
    4. too many hearts; too few diamonds
  15. We run the same experiment with Davia dealing, and we get:
    Suit fo fe
    Hearts 6 6
    Diamonds 5 6
    Spades 4 6
    Clubs 9 6

    We get a Χ2 of:
    1. 3.8
    2. 2.3
    3. .7
    4. 12.8
  16. If we had set α at .05, we should:
    1. reject the null hypothesis
    2. fail to reject the null hypothesis
    3. conclude with certainty that Davia was cheating
    4. not enough information
  17. If we had set α at .01, we should:
    1. reject the null hypothesis
    2. fail to reject the null hypothesis
    3. conclude with certainty that Davia was cheating
    4. not enough information
  18. Chi-square is best for
    1. nominal data
    2. ordinal data
    3. ratio data
    4. interval data
  19. In the chi-square test we have been doing (one-sample), the degrees of freedom equals
    1. 7
    2. the number of categories
    3. the number of categories plus one
    4. the number of categories minus one
  20. If an experiment reports p > .05, and α = .05, we should
    1. reject the null hypothesis
    2. accept the null hypothesis
    3. do the experiment over; something went wrong
    4. conclude that Kenneth is cheating