MSIS 3223 Exam 2 (Ch. 5, 8, 9)
it measures the uncertainty of a random variable. - -Which of the following is true about
variance?
-characterizes outcomes of a continuous random variable. - -A probability density
function:
-time-series - -Regression models of ________ data focus on predicting the future.
-uses a panel of experts, whose identities are typically kept confidential from one another,
to respond to a sequence of questionnaires. - -The Delphi method used for forecasting:
-noted the consumer response to similar previous products to marketing campaigns and
used the responses as a basis to predict how the new marketing campaign might fare. - -
Before launching a new line of toys, Toys Inc. used the method of historical analogy to
obtain a forecast. In this scenario, Toys Inc.:
-classical - -If the process that generates the outcome is known, probabilities can be
deduced from theoretical arguments; this is the _____ definition of probability.
-relative frequency - -The _____ definition of probability is based on empirical data. The
probability that an outcome will occur is simply the relative frequency associated with that
outcome.
-subjective - -The _____ definition of probability is based on judgment and experience as
sports experts might predict at the start of the football season—what is the probability of a
specific team winning the national championship?
-Random variable - -A _____ is a numerical description of the outcome of an
experiment. They can be continuous or discrete.
-discrete random variable - -A _____ is a random variable for which the number of possible
outcomes can be counted.
-continuous random variable - -A _____ is a random variable that has outcomes over one or
more continuous intervals or real numbers.
-expected value - -The _____ of a random variable corresponds to the notion of the mean, or
average for a sample. It can be helpful in making a variety of decisions.
-weighted average of the squared deviations - -The variance of a discrete random variable
may be computed as a _____ from the expected value. A common measure of dispersion.
, -variance - -_____ is the average of the squared deviations of the observations from the
mean, a common measure of dispersion. It measures the uncertainty of the random
variable; the higher it is, the higher the uncertainty of the outcome.
-Bernoulli Distribution - -The probability distribution of a random variable with two
possible outcomes, each with a constant probability of occurrence is referred to as _____.
-Binomial Distribution - -The _____ models n independent replications of a Bernoulli
experiment, each with a probability p of success. The _____ can assume different shapes and
amounts of skewness, depending on the parameters.
-normal distribution - -Perhaps the most important distribution used in statistics, _____ is a
continuous distribution by the familiar bell shaped curve.
-mean and the standard deviation - -Normal distribution is characterized by two
parameters: the _____ and the _____.
-Zero - -Normal distribution is symmetric, so its measure of skewness is _____.
-mean, median, mode - -In normal distribution, the _____, _____, & _____ are all equal. Thus,
half the area falls above the mean and half falls below it.
-unbounded - -In normal distribution, the range of X is _____, meaning that the tails of the
distribution extend to negative & positive infinity.
-empirical rules - -In normal distribution, the _____ apply exactly for it.
-probability density functions - -The distribution that characterizes outcomes of a
continuous random variable.
-x - -Probability Density Functions:
A graph of the density function must lie at or above the _____-axis.
-1 - -Probability Density Functions:
The total area under the density function above the x-axis is _____.
-continuous random variables - -Probability Density Functions:
For _____, there are an infinite number of values.
-probability - -Probability Density Functions:
Calculates the _____ of a random variable lying within a certain interval, such as between
two numbers, or to the left or right of a number.
-p - -Probability Density Functions:
_____ is the area under the density function between a & b.
it measures the uncertainty of a random variable. - -Which of the following is true about
variance?
-characterizes outcomes of a continuous random variable. - -A probability density
function:
-time-series - -Regression models of ________ data focus on predicting the future.
-uses a panel of experts, whose identities are typically kept confidential from one another,
to respond to a sequence of questionnaires. - -The Delphi method used for forecasting:
-noted the consumer response to similar previous products to marketing campaigns and
used the responses as a basis to predict how the new marketing campaign might fare. - -
Before launching a new line of toys, Toys Inc. used the method of historical analogy to
obtain a forecast. In this scenario, Toys Inc.:
-classical - -If the process that generates the outcome is known, probabilities can be
deduced from theoretical arguments; this is the _____ definition of probability.
-relative frequency - -The _____ definition of probability is based on empirical data. The
probability that an outcome will occur is simply the relative frequency associated with that
outcome.
-subjective - -The _____ definition of probability is based on judgment and experience as
sports experts might predict at the start of the football season—what is the probability of a
specific team winning the national championship?
-Random variable - -A _____ is a numerical description of the outcome of an
experiment. They can be continuous or discrete.
-discrete random variable - -A _____ is a random variable for which the number of possible
outcomes can be counted.
-continuous random variable - -A _____ is a random variable that has outcomes over one or
more continuous intervals or real numbers.
-expected value - -The _____ of a random variable corresponds to the notion of the mean, or
average for a sample. It can be helpful in making a variety of decisions.
-weighted average of the squared deviations - -The variance of a discrete random variable
may be computed as a _____ from the expected value. A common measure of dispersion.
, -variance - -_____ is the average of the squared deviations of the observations from the
mean, a common measure of dispersion. It measures the uncertainty of the random
variable; the higher it is, the higher the uncertainty of the outcome.
-Bernoulli Distribution - -The probability distribution of a random variable with two
possible outcomes, each with a constant probability of occurrence is referred to as _____.
-Binomial Distribution - -The _____ models n independent replications of a Bernoulli
experiment, each with a probability p of success. The _____ can assume different shapes and
amounts of skewness, depending on the parameters.
-normal distribution - -Perhaps the most important distribution used in statistics, _____ is a
continuous distribution by the familiar bell shaped curve.
-mean and the standard deviation - -Normal distribution is characterized by two
parameters: the _____ and the _____.
-Zero - -Normal distribution is symmetric, so its measure of skewness is _____.
-mean, median, mode - -In normal distribution, the _____, _____, & _____ are all equal. Thus,
half the area falls above the mean and half falls below it.
-unbounded - -In normal distribution, the range of X is _____, meaning that the tails of the
distribution extend to negative & positive infinity.
-empirical rules - -In normal distribution, the _____ apply exactly for it.
-probability density functions - -The distribution that characterizes outcomes of a
continuous random variable.
-x - -Probability Density Functions:
A graph of the density function must lie at or above the _____-axis.
-1 - -Probability Density Functions:
The total area under the density function above the x-axis is _____.
-continuous random variables - -Probability Density Functions:
For _____, there are an infinite number of values.
-probability - -Probability Density Functions:
Calculates the _____ of a random variable lying within a certain interval, such as between
two numbers, or to the left or right of a number.
-p - -Probability Density Functions:
_____ is the area under the density function between a & b.
