BNAD 276 Exam 1 Review

A population consists of:

All items of interest in a statistical problem.

What is a characteristic of the mass function of a discrete random variable X? A. The sum of probabilities P(X =x) over all possible values x is 1. B. For every possible value x, the probability P(X =x) is between 0 and 1. C. Describes all possible values x with the associated probabilities P(X =x) . D.All the above.

All the above

What are the two key properties of a discrete probability distribution? A. 0≤P(X = x)≤1 and ∑P (X = xi ) = 0 B. 0≤P(X = x)≤1 and ∑P (X = xi ) = 1 C. -1≤P(X = x)≤1 and ∑P (X = xi ) = 1 D. -1≤P(X = x)≤1 and ∑P (X = xi ) = 0

B. 0≤P(X = x)≤1 and ∑P (X = xi ) = 1

Which of the following is an example of time series data?

B. Quarterly housing starts collected over the last 60 years

For both qualitative and quantitative data, what is the difference between the relative frequency and the percent frequency? A. The relative frequency equals the percent frequency multiplied by 100. B. The percent frequency equals the relative frequency multiplied by 100. C. As opposed to the relative frequency, the percent frequency is divided by the number of observations in the data set. D. As opposed to the percent frequency, the relative frequency is divided by the number of observations in the data set.

B. The percent frequency equals the relative frequency multiplied by 100.

The intersection of events A and B, denoted by,

Contains outcomes that are both in A and B

What type of relationship is indicated in the scatterplot? A. No relationship B. A negative linear relationship C. A negative curvilinear relationship D. A positive linear or curvilinear relationship

D. A positive linear or curvilinear relationship

In what way(s) is(are) the concept of geometric mean useful? A. In evaluating investment returns B. In calculating average growth rates C. In assessing the dispersion of the data D. Both in evaluating investment returns and in calculating average growth rates

D. Both in evaluating investment returns and in calculating average growth rates

A qualitative variable assumes meaningful numerical values.

False

Headline of newspaper states "What global warming?" after record amounts of snow in 2010. Problem with Conclusion:

Incorrect to draw conclusion based on one data point.

The Fahrenheit scale of measuring temperature would be classified as a(n)

Interval scale

What is (are) characteristic(s) of the geometric mean?

It is always less than or equal to the arithmetic mean.

Which of the following statements about the mean absolute deviation (MAD) is the most accurate?

It is denominated in the same unites as the original data.

Why would median be used instead of mean?

Mean is influenced by outliers.

Give an example of qualitative data

Name, gender, political party, etc

What is the least sophisticated level of measurement?

Nominal

Differences between categories are meaningless with _________ data.

Ordinal

What level of measurement are differences between the categories meaningless?

Ordinal

What is the most sophisticated level of measurement?

Ratio

The sharpe ratio measure what?

Reward per unit of risk

What estimates a population parameter?

Sample Statistic

Correlation might also be described as

Standard Covariance

A Boston Globe poll reported a 15-point lead for Martha Coakley in the election for U.S. senator for Massachusetts, implying an easy win for Coakley. Nine days later, Scott Brown wins. Problem with conclusion:

The Globe's prediction was based on old information and included people that were unlikely to vote.

For which of the following population parameters is sampling not necessary? A. The average height of NBA players B. The average life of light bulbs produced by a manufacturer C. The average content of cereal boxes produced by a manufacturer D. The percentage of the U.S. public school teachers who support Democrats

The average height of NBA players

The Sharpe ratio measures

The extra reward per unit of risk

A gambler predicts that he will roll a 7 on his next roll of the dice since he was unsuccessful in the last three rolls. Problem with Conclusion:

The probability of rolling a 7 stays constant with each roll of the dice.

1) Which of the following can be represented by a continuous random variable? A. The time of a flight between Chicago and New York B. The number of defective light bulbs in a sample of five C. The number of arrivals to a drive-through bank window in a four-hour period D. The score of a randomly selected student on a five-question multiple-choice quiz

The time of a flight between Chicago and New York

What symbol represents an intersection?

Union

Which of the following is an example of qualitative data? A. Today's high temperature B. The class average of last test C. The amount of time you spent for your homework D. Your last name

Your last name