Statistics True/False with corrections
(Sample statistics) are represented by letters from the Greek alphabet
False, population parameters
When r is positive, b1 will always be negative
False, positive
When the calculated value of r is positive, the calculated value of b1 will be (negative)
False, positive
The "number of rotten apples per shipping crate" is an example of a (qualitative) variable
False, quantitative
A (frequency) sample is obtained in such a way that all possible samples of a given size have an equal chance of being selected
False, random
A (representative) sample is a sample obtained in such a way that all individuals had an equal chance to be selected
False, random
(Correlation) analysis is a method of obtaining the equation that represents the relationship between two variables
False, regression
When using the notation Z(0.05), the number in parentheses is the measure of the area to the (left) of the z-score
False, right
A statistic is the calculated measure of some characteristic of a (population)
False, sample
The standard error of the mean is the standard deviation of the (sample selected)
False, sample distribution of the mean
A (probability) distribution of a sample statistic is a distribution of all the values of that statistic that were obtained from all possible samples
False, sampling
The value found for experimental probability will (always be) exactly equal to the theoretical probability assigned to the same event
False, seldom
The sample points of a sample space are (equally likely) events
False, simple
Probability distributions of (all) continuous random variables are normally distributed
False, some (many)
The histograms of (all) sampling distributions are symmetrically shaped
False, some (many)
The linear correlation coefficient is used to determine the (equation that represents) the relationship between two variables
False, strength of the
The probabilities of complementary events always (are equal)
False, sum to 1.0
Failing to reject the null hypothesis when it is false is a (correct decision)
False, type II error
The standard deviation for the set of values 2,2,2,2, and 2 is (2)
False, zero
Standard normal scores have a mean of (one) and a standard deviation of (zero)
False, zero, 1
A correlation coefficient of (zero) means that the two variables are perfectly correlated
False, +1 or -1
Correlation coefficients range between 0 and +1
False, -1 and +1
(1−α) is known as the level of significance of a hypothesis test
False, alpha
(Beta) is the probability of a type 1 error
False, alpha
The probability of an event is a (whole number)
False, any number value between 0 and 1, inclusive
The shape of the distribution of sample means is always that of a (normal) distribution
False, approximately normal
As a result of surveying 50 freshmen, it was found that 16 had participated in interscholastic sports, 23 had served as officers of classes and clubs, and 18 had been in school plays during their high school years. This is an example of (numerical data)
False, attribute or qualitative
If the noncritical region in the hypothesis test is made wider (assuming σ and n remain fixed), (α) becomes larger
False, beta
The formula μ = np may be used to compute the mean of a (discrete) population
False, binomial
If events A and B are (mutually exclusive), the sum of their probabilities must be exactly one
False, complementary
The number of hours you waited in line to register this semester is an example of a (discrete) random variable
False, continuous
Rejection of a null hypothesis that is false is a (type 2 error)
False, correct decision
To conclude that the mean is higher (or lower) than a claimed value, the value of the test statistic must fall in the (acceptance region)
False, critical (rejection) region
The standard error of the mean (increases) as the sample size increases
False, decreases
If two events are mutually exclusive, they are also (independent)
False, dependent
(Inferential) statistics is the study and description of data that result from an experiment.
False, descriptive
A measure of (central tendency) is a quantitative value that describes how widely the data are dispersed about a central value
False, dispersion
The standard error of the mean is the standard deviation of the population (from which the samples have been taken)
False, divided by the root of n
A binomial experiment always has (three or more) possible outcomes to each trial
False, exactly two
On a test John scored at the 50th percentile and Jorge scored at the 25th percentile; therefore. John's test score was (twice) Jorge's test score.
False, higher than
(Descriptive statistics) is the study of a sample that enables us to make projections or estimates about the population from which the sample is drawn.
False, inferential
A sampling distribution (is) a distribution listing all the sample statistics that describe a particular sample
False, is not
The normal probability distribution is symmetric about (zero)
False, its mean
The Central Limit Theorem provides us with a description of the three characteristics of a sampling distribution of sample (medians)
False, means
The (mean) of a sample always divides the data into two equal halves (half larger and half smaller in value than itself)
False, median
A compound event formed by use of the word and requires the use of the (addition rule)
False, multiplication rule
We are able to add and subtract the areas under the curve of a continuous distribution because these areas represent probabilities of (independent) events
False, mutually exclusive events
If the sets of sample points belonging to two different events do not intersect, the events are (independent)
False, mutually exclusive or dependent
The sum of the squares of the deviations from the mean, Σ(x-x̄)², will (sometimes) be negative
False, never
The most common distribution of a continuous random variable is the (binomial) probability
False, normal
The sum of all the probabilities in any probability distribution is always exactly (two)
False, one
The unit of measure for the standard score is the (same as the unit of measure of the data)
False, one standard deviation
The binomial parameter p is the probability of (one success occurring in n trials) when a binomial experiment is performed
False, one success occurring on one trial
The value being predicted is called the (input) variable
False, output or predicted value
A parameter is a statistical measure of some aspect of a (sample)
False, population
A parameter is the measure of some characteristic of a (sample)
False, population
The mean of the sampling distribution of x̄'s equal to the mean of the (sample)
False, population
(Frequency distributions) are used in statistics to present large quantities of repeating values in a concise form
True
A (population) is typically a very large collection of individuals or objects about which we desire information.
True
All (normal) distributions have the same general probability function and distribution
True
Alpha is the measure of the area under the curve of the standard score that lies in the (rejection region) for the null hypothesis
True
For a bell-shaped distribution, the range will be approximately equal to (six standard deviations)
True
For any distribution, the sum of the deviations from the mean equals (zero)
True
The "thickness of a sheet of sheet metal" used in a manufacturing process is an example of a (quantitative) variable
True
The (sample space) is the theoretical population for probability problems
True
The (slope) of the regression line represents the amount of change expected to take place in y when x increases by one unit
True
The basic objective of (statistics) is that of obtaining a sample, inspecting the sample, and then making inferences about the unknown characteristics of the population from which the sample was drawn
True
The concepts of probability and relative frequency as related to an event are (very similar)
True
The frequency of a class is the number of pieces of data whose values fall within the (boundaries) of that class
True
The line of best fit is used to predict the (average value of y) that can be expected to occur at a given value of x
True
The maximum error of estimate is controlled by three factors: (level of confidence, sample size, and standard deviation)
True
The number of automobile accidents you were involved in as a driver last year is an example of a (discrete) random variable
True
The probability of event A or B is equal to the sum of the probability of event A and the probability of event B when A and B are (mutually exclusive)
True
The risk of making a (type 1 error) is directly controlled in a hypothesis test by establishing a level for α
True
The theoretical probability that a particular value of a (continuous) random variable will occur is exactly zero
True
The total area under the curve of any normal distribution is (1.0)
True
The unit of measure for the standard score is always in (standard deviations)
True
The various values of a random variable form a list of (mutually exclusive events)
True
We (do not need) to repeatedly sample a population in order to use the concept of the sampling distribution
True
Whenever the slope of the regression line is zero, the (correlation coefficient) will also be zero
True