The following data represent a sample of 10 scores on a 20-point statistics quiz: 16, 16, 16, 16, 16, 18, 18, 20, 20, and 20 . After the mean, median, range and variance were calculated for the scores, it was discovered that one of the scores of 20 should have been an 18 . Which of the following will change when the calculations are redone using the correct scores?
a. mean and range
b. median and range
c. mean and variance
d. range and variance
e. mean, range, median and variance
Q. 2Which of the following is the name given to rejecting the null hypothesis when it is true?
a. Type A correct decision.
b. Type B correct decision.
c. Type I error.
d. Type II error.
Q. 3A random sample from an unknown population had a sample standard deviation of zero. Which one of the following is a reasonable conclusion?
a. The sample range must be zero.
b. An error was made in computing the sample standard deviation. It must always be greater than zero.
c. The population standard deviation must be zero.
d. The population standard deviation must be zero when the mean is zero.
e. None of these.
Q. 4You have rejected the null hypothesis when it is false, and therefore you have made a
a. Type A correct decision.
b. Type B correct decision.
c. Type I error.
d. Type II error.
Q. 5Which of the following statements about the median is correct?
a. It is a measure of center that divides an ordered array of data into two halves.
b. If data are arranged in ascending order from smallest to largest, all the observations below the median are smaller than or equal to it, while all the observations above the median are equal to it or larger.
c. If the total number of observations is odd, the median is the middle observation in an ordered array; if the total number of observations is even, the median is the average of the two middle values.
d. All of these.
e. None of these.
Q. 6The Type I error often results in what represents a lost opportunity.
Indicate whether the statement is true or false
Q. 7Consider the data set: 5, 6, 7, 11, and 15 . Its mean equals:
a. 7.0
b. 8.8
c. 8.1
d. 7.3
e. 9
Q. 8A Type II error is committed when we decide in favor of a null hypothesis that is actually false.
Indicate whether the statement is true or false
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