1. The portion of the universe that has been selected for analysis is called:
Answer a sample
a frame
a parameter
a statistic
Question 2
One of the advantages of a pie chart is that it clearly shows that the total of all the categories of the pie adds to 100%.
Answer
True
False
Question 3
Which of the 4 methods of data collection is involved when a person counts the number of cars passing designated location on the Los Angeles freeway system?
Answer published sources
experimentation
surveying
observation
Question 4
The coefficient of variation is a measure of the central tendency in the data. Answer
True
False
Question 5
Which of the following is NOT a measure of central tendency?
Answer
the arithmetic mean
the geometric mean
the mode
the interquartile range
Question 6
A Pareto diagram is a bar chart in which the bars are naturally arranged with a decreasing pattern:
Answer
True
False
-Question 7
If two events are collectively exhaustive, what is the probabiltiy that one or the other occurs?
Answer
0
.50
1.00
Can not be determined with the information given
Question 8
The cross-tabulation of two categorical variables leads to a contingency table:
Answer
True
False
Question 9
A business venture can result in the following outcomes (with their corresponding chance of occuring in parenthesis); Highly Successful (10%), Successful (25%), Break Even (25%), Disappointing (20%), and Highly Disappointing (?). If these are the only outcomes possible for the business venture, what is the chance that the business venture will be considered Highly Disappointing?
Answer
10%
15%
20%
25%
4 points
Question 10
A population consists of all the possible objects to be studied:
Answer
True
False
4 points
Question 11
An economics professor bases his final grade on homework, two midterm examinations, and a final examination. The homework counts 10% toward the final grade, while each midterm counts 25%. The remaining porttion consists of the final exam. If a student scored 95% in homework, 70% on the first midterm, 96% on the second midterm, and 72% on the final exam, his final average is 79.8%
Answer
True
False
4 points
Question 12
If event A and Event B cannot occur at the same point in time, then events A and B are said to be
Answer
mutually exclusive
statistically independent
collectively exhaustive
none of the above
4 points
Question 13
Thirty-six of the staff of 80 teachers at a local intermediate school are certified in Cardio-Pulmonary Resuscitation (CPR). In 180 days of school, about how many days can we expect that the teacher on bus duty will likely be certified in CPR
Answer 5 Days
45 Days
65 days
81 Days
4 points
Question 14
If we randomly draw a ball from a bag with a finite number of balls in it, then put the ball back into the bag and randomly draw another ball from the bag, this is an example of sampling with replacement
Answer
True
False
4 points
Question 15
The Standard Normal distribution has a mean of 1 and a standard deviation of 1.
Answer
True
False
4 points
Question 16
Marginal probability is also called
Answer
Simple probability
Conditional probability
Joint probability
Bayes' theorem
4 points
Question 17
If n = 10 and p = 0.70, then the standard deviation of the binomial distribution is
Answer 0.07
1.45
7.00
14.29
4 points
Question 18
In its standardized form, the normal distribution
Answer has a mean of 0 and a standard diviation of 1.
has a mean of 1 and a variance of 0.
has an area equal to .05
cannot be used to aprroximate discrete probability distribution.
4 points
Question 19
The "empirical rule" for the bell-shaped curve states that the percentage of data points falling within three standard deviations away from the mean is 99.7%
Answer
True
False
4 points
Question 20
Distribution 1 is a skewed distribution and Distribution 2 is a symmetric distribution (not Normal distribution). Similar sample sizes will be required for the sample mean of random samples from the two distributions to have an approximate Normal distribution.
Answer
True
False
4 points
Question 21
The null hypothesis Ho always contains an equal sign
Answer
True
False
4 points
Question 22
If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected college student will find a parking spot in the library parking lot in less than 3 minutes.
Answer 0.3551
0.3085
0.2674
0.1915
4 points
Question 23
If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the point in the distiribution that 75.8% of the college students exceed when trying to find a parking spot in the library parling lot.
Answer
2.8 minutes
3.2 minutes
3.4 minutes
4.2 minutes
4 points
Question 24
The fact that the sample means are less variable than the population data can be observed form the standard error of the mean.
Answer
True
False
4 points
Question 25
In left-skewed distribution, the median is
Answer
equal to the mean
greater than the mean
less than the mean
none of the above