MSIS 3223 Exam 2 Review questions
and answers already passed
Classical Definition of Probability - correct answer ✔✔If the process that generates the outcome
is known, probabilities can be deduced from theoretical arguments
Relative Frequency definition - correct answer ✔✔Based on empirical data; The probability that
an outcome can occur is the relative frequency associated with that outcome.
Subjective definition of probability - correct answer ✔✔based on judgement and experience
Random Variable - correct answer ✔✔a numerical description of the outcome of an experiment
Discrete random variable - correct answer ✔✔a variable for which the number of possible
outcomes can be counted
continuous random variable - correct answer ✔✔has outcomes over one or more continuous
intervals or real numbers
Expected Value - correct answer ✔✔corresponds to the mean or average of a sample; can be
helpful in making a variety of decisions
Weighted average of the squared deviations from the expected value - correct answer ✔✔the
variance of a discrete random variable may be computed as a(an); is a common measure of
dispersion
, Variance - correct answer ✔✔Measures the uncertainty of a random variable; the higher the
_______, the higher the uncertainty of an outcome
binomial distribution - correct answer ✔✔can assume differences in the amount of skewness
depending on the parameters
Normal Distribution - correct answer ✔✔The most important distribution used in statistics,
_______ is a continuous distribution described by the familiar bell shaped curve
True - correct answer ✔✔T/F, The Normal distribution is characterized by two parameters: the
mean and standard deviation
True - correct answer ✔✔T/F The distribution is symmetric, so it's measure of skewness is zero
False - correct answer ✔✔in a normal distribution, the mean, median, and mode are not equal
True - correct answer ✔✔in a normal distribution, the range of x is unbounded, meaning the
tails of a distribution extend to negative and positive infinity
Probability density functions - correct answer ✔✔the distribution that characterizes the
outcomes of a continuous random variable
Properties of probability density functions - correct answer ✔✔•A graph of the density function
must lie at or above the x-axis.
•The total area under the density function above the x-axis is 1.
•For continuous random variables, there are an infinite number of values.
•Calculates the probability of a random variable lying within a certain interval such as between
two numbers, or to the left or right of a number.
•P is the area under the density function between a and b.
and answers already passed
Classical Definition of Probability - correct answer ✔✔If the process that generates the outcome
is known, probabilities can be deduced from theoretical arguments
Relative Frequency definition - correct answer ✔✔Based on empirical data; The probability that
an outcome can occur is the relative frequency associated with that outcome.
Subjective definition of probability - correct answer ✔✔based on judgement and experience
Random Variable - correct answer ✔✔a numerical description of the outcome of an experiment
Discrete random variable - correct answer ✔✔a variable for which the number of possible
outcomes can be counted
continuous random variable - correct answer ✔✔has outcomes over one or more continuous
intervals or real numbers
Expected Value - correct answer ✔✔corresponds to the mean or average of a sample; can be
helpful in making a variety of decisions
Weighted average of the squared deviations from the expected value - correct answer ✔✔the
variance of a discrete random variable may be computed as a(an); is a common measure of
dispersion
, Variance - correct answer ✔✔Measures the uncertainty of a random variable; the higher the
_______, the higher the uncertainty of an outcome
binomial distribution - correct answer ✔✔can assume differences in the amount of skewness
depending on the parameters
Normal Distribution - correct answer ✔✔The most important distribution used in statistics,
_______ is a continuous distribution described by the familiar bell shaped curve
True - correct answer ✔✔T/F, The Normal distribution is characterized by two parameters: the
mean and standard deviation
True - correct answer ✔✔T/F The distribution is symmetric, so it's measure of skewness is zero
False - correct answer ✔✔in a normal distribution, the mean, median, and mode are not equal
True - correct answer ✔✔in a normal distribution, the range of x is unbounded, meaning the
tails of a distribution extend to negative and positive infinity
Probability density functions - correct answer ✔✔the distribution that characterizes the
outcomes of a continuous random variable
Properties of probability density functions - correct answer ✔✔•A graph of the density function
must lie at or above the x-axis.
•The total area under the density function above the x-axis is 1.
•For continuous random variables, there are an infinite number of values.
•Calculates the probability of a random variable lying within a certain interval such as between
two numbers, or to the left or right of a number.
•P is the area under the density function between a and b.
