BAN 122: Practice Questions

A continuous random variable may assume a. all values in an interval or collection of intervals b. only integer values in an interval or collection of intervals c. only fractional values in an interval or collection of intervals d. all the positive integer values in an interval

A

A normal probability distribution a. is a continuous probability distribution b. is a discrete probability distribution c. can be either continuous or discrete d. always has a standard deviation of 1

A

A numerical measure, such as a mean, computed from a population is known as a a. population parameter b. sample parameter c. sample statistic d. sample mean

A

Data collected over several time periods are a. time series data b. time controlled data c. cross-sectional data d. time cross-sectional data

A

Exhibit 3-1 A researcher has collected the following sample data. 5 12 6 8 5 6 7 5 12 4 Refer to Exhibit 3-1. The mode is a. 5 b. 6 c. 7 d. 8

A

Exhibit 6-3 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. Refer to Exhibit 6-3. What is the random variable in this experiment? a. the weight of football players b. 200 pounds c. 25 pounds d. the normal distribution

A

For ease of data entry into a university database, 1 denotes that the student is an undergraduate and 2 indicates that the student is a graduate student. In this case data are a. qualitative b. quantitative c. either qualitative or quantitative d. neither qualitative nor quantitative

A

If the variance of a data set is correctly computed with the formula using n 1 in the denominator, which of the following is true? a. the data set is a sample b. the data set is a population c. the data set could be either a sample or a population d. the data set is from a census

A

In a standard normal distribution, the range of values of z is from a. minus infinity to infinity b. -1 to 1 c. 0 to 1 d. -3.09 to 3.09

A

Mu (greek u) is an example of a a. population parameter b. sample statistic c. population variance d. mode

A

The collection of all elements of interest in a particular study is a. the population b. the sampling c. statistical inference d. descriptive statistics

A

The uniform probability distribution is used with a. a continuous random variable b. a discrete random variable c. a normally distributed random variable d. any random variable

A

The variance of the sample a. can never be negative b. can be negative c. cannot be zero d. cannot be less than one

A

The weight of an object, measured in grams, is an example of a. a continuous random variable b. a discrete random variable c. either a continuous or a discrete random variable, depending on the weight of the object d. either a continuous or a discrete random variable depending on the units of measurement

A

A standard normal distribution is a normal distribution with a. a mean of 1 and a standard deviation of 0 b. a mean of 0 and a standard deviation of 1 c. any mean and a standard deviation of 1 d. any mean and any standard deviation

B

An experiment consists of measuring the speed of automobiles on a highway by the use of radar equipment. The random variable in this experiment is speed, measured in miles per hour. This random variable is a a. discrete random variable b. continuous random variable c. complex random variable d. None of the answers is correct.

B

Exhibit 3-1 A researcher has collected the following sample data. 5 12 6 8 5 6 7 5 12 4 Refer to Exhibit 3-1. The median is a. 5 b. 6 c. 7 d. 8

B

Exhibit 3-2 A researcher has collected the following sample data. The mean of the sample is 5. 3 5 12 3 2 Refer to Exhibit 3-2. The standard deviation is a. 8.944 b. 4.062 c. 13.2 d. 16.5

B

Exhibit 6-3 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. Refer to Exhibit 6-3. The probability of a player weighing more than 241.25 pounds is a. 0.4505 b. 0.0495 c. 0.9505 d. 0.9010

B

Exhibit 6-3 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. Refer to Exhibit 6-3. What is the minimum weight of the middle 95% of the players? a. 196 b. 151 c. 249 d. None of the alternative answers is correct.

B

For the standard normal probability distribution, the area to the left of the mean is a. -0.5 b. 0.5 c. any value between 0 to 1 d. 1

B

Given that z is a standard normal random variable, what is the value of z if the area to the left of z is 0.9382? a. 1.8 b. 1.54 c. 2.1 d. 1.77

B

Qualitative data a. are always nonnumeric b. may be either numeric or nonnumeric c. are always numeric d. indicate either how much or how many

B

Temperature is an example of a. a qualitative variable b. a quantitative variable c. either a quantitative or qualitative variable d. neither a quantitative nor qualitative variable

B

The ages of students at a university are normally distributed with a mean of 21. What percentage of the student body is at least 21 years old? a. It could be any value, depending on the magnitude of the standard deviation b. 50% c. 21% d. 1.96%

B

The process of analyzing sample data in order to draw conclusions about the characteristics of a population is called a. descriptive statistics b. statistical inference c. data analysis d. data summarization

B

The standard deviation of a standard normal distribution a. is always equal to zero b. is always equal to one c. can be any positive value d. can be any value

B

A numerical measure computed from a sample, such as sample mean, is known as a a. population parameter b. sample parameter c. sample statistic d. population mean

C

Data collected at the same, or approximately the same, point in time are a. time series data b. approximate time series data c. cross-sectional data d. approximate data

C

Excel's NORMDIST function can be used to compute a. cumulative probabilities for a standard normal z value b. the standard normal z value given a cumulative probability c. cumulative probabilities for a normally distributed x value d. the normally distributed x value given a cumulative probability

C

Exhibit 3-1 A researcher has collected the following sample data. 5 12 6 8 5 6 7 5 12 4 Refer to Exhibit 3-1. The mean is a. 5 b. 6 c. 7 d. 8

C

For a standard normal distribution, a negative value of z indicates a. a mistake has been made in computations, because z is always positive b. the area corresponding to the z is negative c. the z is to the left of the mean d. the z is to the right of the mean

C

Quantitative data a. are always nonnumeric b. may be either numeric or nonnumeric c. are always numeric d. are always labels

C

The numerical value of the standard deviation can never be a. larger than the variance b. zero c. negative d. all of these statements are correct

C

The population variance can never be a. zero b. larger than the standard deviation c. negative d. all of these are correct

C

The sample variance a. is always smaller than the true value of the population variance b. is always larger than the true value of the population variance c. could be smaller, equal to, or larger than the true value of the population variance d. can never be zero

C

A portion of the population selected to represent the population is called a. statistical inference b. descriptive statistics c. a census d. a sample

D

Excel's __________ function can be used to compute the population variance. a. VARIANCE b. STDEV c. VAR d. None of the other answers are correct.

D

Excel's __________ function can be used to compute the sample standard deviation. a. STDEVP b. STANDARDIZE c. STANDARD d. STDEV

D

Exhibit 3-2 A researcher has collected the following sample data. The mean of the sample is 5. 3 5 12 3 2 Refer to Exhibit 3-2. The variance is a. 80 b. 4.062 c. 13.2 d. 16.5

D

Exhibit 6-3 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. Refer to Exhibit 6-3. The probability of a player weighing less than 250 pounds is a. 0.4772 b. 0.9772 c. 0.0528 d. 0.5000

D

Exhibit 6-3 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. Refer to Exhibit 6-3. What percent of players weigh between 180 and 220 pounds? a. 34.13% b. 68.26% c. 0.3413% d. None of the alternative answers is correct.

D

For any continuous random variable, the probability that the random variable takes on exactly a specific value is a. 1.00 b. 0.50 c. any value between 0 to 1 d. zero

D

Larger values of the standard deviation result in a normal curve that is a. shifted to the right b. shifted to the left c. narrower and more peaked d. wider and flatter

D

Since a sample is a subset of the population, the sample mean a. is always smaller than the mean of the population b. is always larger than the mean of the population c. must be equal to the mean of the population d. can be larger, smaller, or equal to the mean of the population

D

Since the population size is always larger than the sample size, then the sample statistic a. can never be larger than the population parameter b. can never be equal to the population parameter c. can never be zero d. None of the other answers are correct.

D

The mean of a sample is a. always equal to the mean of the population b. always smaller than the mean of the population c. computed by summing the data values and dividing the sum by (n -1) d. computed by summing all data values and dividing it by the number of items

D

The mean of a standard normal probability distribution a. is always equal to 1 b. can be any value as long as it is positive c. can be any value d. None of the alternative answers is correct.

D

The mean of the sample a. is always larger than the mean of its' population b. is always smaller than the mean of its' population c. can never be zero d. None of the other answers are correct.

D

The sum of deviations of the individual data elements from their mean is a. always greater than zero b. always less than zero c. sometimes greater than and sometimes less than zero, depending on the data d. always equal to zero

D

The value of the sum of the squared deviations from the mean, i.e., must always be a. less than the mean b. negative c. either positive or negative depending on whether the mean is negative or positive d. at least zero

D

Which of the following is not a characteristic of the normal probability distribution? a. The mean, median, and the mode are equal b. The mean of the distribution can be negative, zero, or positive c. The distribution is symmetrical d. The standard deviation must be 1

D

Z is a standard normal random variable. The P(1.41 < z < 2.85) equals a. 0.4772 b. 0.3413 c. 0.8285 d. None of the alternative answers is correct.

D

Z is a standard normal random variable. The P(z > 2.11) equals a. 0.4821 b. 0.9821 c. 0.5 d. 0.0174

D