What measures central location for data

Mean, median mode

When computing the mean of a set of values, the sum of the values

Can be any value

In computing the mean of a sample, the value of the sum is divided by

n

A numerical value used as a summary measure for a sample, such as sample mean, is known as a

sample statistic

Since the population size is always larger than the sample size, then the sample statistic

can be smaller, larger, or equal to the population parameter.

The greek symbol, μ is an example of a

population parameter

The mean of a sample

is computed by summing all the data values and dividing the sum by the number of items

The median of a sample will always equal

the 50th percentile

The median is a measure of

central location

The 50th percentile is

the median

The 75th percentile is referred to as the

third quartile.

The pth percentile is a value that at least p percent of the observations are

less than or equal to this value

The difference between the largest and the smallest data values is the

range

The first quartile

is the same as the 25th percentile

In computing the hinges for data with an odd number of items, the median position is included

both in the computation of the lower and upper hinges.

What are the measures of dispersion?

Variance, range, interquartile range, and standard deviation

The interquartile range is

the difference between the third quartile and the first quartile.

When the data are skewed to the right, the measure of skewness will be

positive.

When data are positively skewed, the mean will usually be

greater than the median.

The interquartile range is used as a measure of variability to overcome what difficulty of the range?

The range is influenced too much by extremes.

If the variance of a data set is correctly computed with the formula using n-1 in the denominator, what is true?

The data set is a sample.

In computing descriptive statistics from grouped data,

data values are treated as if they occur at the midpoint of a class

The measure of dispersion that is influenced by extreme values is

the range

When should measures of location and dispersion be computed from grouped data rather than from individual data values?

Only when individual data values are unavailable

The descriptive measure of dispersion that is based on the concept of a deviation about the mean is?

The standard deviation

The measure of location which is the most likely to be influenced by extreme values is the data set is the?

Mean

The numerical value of the standard deviation can never be

Negative.

The counting rule that is used for counting the number of experimental outcomes when n objects are selected from a set of N objects were order of selection is not important is called?

Combination

The counting rule that is used for counting the number of experimental outcomes when n objects are selected from a set of N objects were order of selection is important is called?

Permutation

Each individual outcome of an experiment is called

a sample point

The collection of all possible sample points is an experiment is

the sample space

The graphical method of representing the sample points of an experiment is

a tree diagram

In statistical experiments, each time the experiment is repeated

a different outcome may occur.

When the assumption of equally likely outcomes is used to assign probability values, the method used to assign probabilities is referred to as the

classical method

The range of probability is

zero to one

Two events, A and B, are mutually exclusive and each have a nonzero probability. If event A is known to occur, the probability of the occurrence of even B is

zero.

The addition law is potentially helpful when we are interested in computing the probability of

the union of two events

The multiplication law is potentially helpful when we are interested in computing the probability of

the intersection of two events.

If two events are mutually exclusive, then their intersection

will be equal to zero

The union of events A and B is the even containing

all the sample points belonging to A or B, or both

If a penny is tossed three times and comes up heads all three times, the probability of heads on the fourth trial is

one-half

Which of the following is a required condition for a discrete probability function?

Σf(x) = 1

A measure of the average value of a random variable is called an

expected value

The standard deviation is the

positive square root of the variance

The variance is the measure of the dispersion or variability of a random variable. It is a weighted average of the

squared deviations from the mean

A weighted average of the value of a random variable, where the probability function provides weights is known as

the expected value

The weight of an object is an example of

A continuous random variable

When sampling without replacement, the probability of obtaining a certain sample is best given by a

hypergeometric distribution

In the textile industry, a manufacturer is interested in the number of blemishes or flaws occurring in each 100 feet of material. The probability distribution that has the greatest chance of applying to this situation is the

poisson distribution

The poisson probability distribution is a

discrete probability distribution

The binomial probability distribution is used with

a discrete random variable.

What are the characteristics of an experiment where the binomial probability distribution is applicable?

The experiment has a sequence of n identical trials, exactly two outcomes are possible on each trial, the probabilities of the outcomes do not change from one trial to another.

What is a characteristic of a binomial experiment

the trials are independent.

What are the properties of a binomial experiment?

The experiment consists of a sequence of n identical trials, each outcome can be referred to as a success or failure, the trials are independent.

When dealing with the number of occurrences of an event over a specified interval of time or space, the appropriate probability distribution is a

poisson distribution

The key difference between the binomial and hypergeometric distribution is that with the hypergeometric distribution

the probability of success changes from trial to trial

A random variable that may take on any value in an interval or collection of intervals is known as

A continuous random variable.