stats final
f the alternative hypothesis is that proportion of items in population 1 is larger than the proportion of items in population 2, then the null hypothesis should be:
.p1 -p2 =0
A tabular method that can be used to summarize the data on two variables simultaneously is called:
a crosstabulation
A boxplot is a graphical representation of data that is based on:
a five number summary
Categorical data can be graphically represented by using a(n):
bar chart
A graphical summary of data that is based on a five-number summary is a:
boxplot
Posterior probabilities are:
conditional probabilities
An exponential probability distribution is a _____ distribution.
continuous
Highway patrol officers measure the speed of automobiles on a highway using radar equipment. The random variable in this experiment is speed, measured in miles per hour. This is a ____ random variable.
continuous
As the sample size increases, the margin of error _____
decreases
The summaries of data, which may be tabular, graphical, or numerical, are referred to as:
descriptive statistics
A marketing manager instructs his team to make 80 telephone calls to attempt to sell an insurance policy. The random variable in this experiment is the number of sales made. This is a ___ random variable.
discrete
The symbol ∩ shows the _____ of events.
intersection
a university official collected a sample of 59 out of state plate vehicles because he believes that they are more likely to park without a valid permit
judgement
We can use the normal distribution to make confidence interval estimates for the population proportion, p, when:
np ≥ 5 and n(1 − p) ≥ 5
The number of degrees of freedom for the appropriate 𝜒^2 distribution in a test of independence is:
number of rows minus 1 times number of columns minus 1
Two approaches to drawing a conclusion in a hypothesis test are:
p value and critical value
The general form of an interval estimate of a population mean or population proportion is the _____ plus or minus the _____.
point estimate, margin of error
Which of the following is an example of quantitative data?
the number of people waiting in a line
The sample space refers to:
the set of all possible experimental outcomes
Which of the following is a characteristic of a binomial experiment?
the trials are independent
A graphical method of representing the outcomes of a multiple-step process is a(n):
tree diagram
A goodness of fit test is always conducted as a(n):
upper tail test
a university official selects every 5th vehicles that comes out of the university street garage to form a sample of 50 vehicles.
systematic
Which of the following is not a measure of variability?
50th percentile
The number of observations in a complete data set having 10 elements and 5 variables is:
10
What is the difference between a bar graph and a histogram?
A bar graph displays categorical data, while a histogram displays quantitative data.
A measure of the average value of a random variable is also called a(n):
A measure of the average value of a random variable is also called a(n):
Your investment executive claims that the average yearly rate of return on the stocks she recommends is at least 10%. You plan on taking a sample to test her claim. The correct set of hypotheses is
H0: μ = 10 Ha: μ < 10
The random variable X is the number of occurrences of an event over an interval of 10 minutes. It can be assumed the probability of an occurrence is the same in any two time periods of an equal length. It is known that the mean number of occurrences in 10 minutes is 5.3. The random variable X satisfies which of the following probability distributions?
Poisson
A random variable that can assume only whole number values is referred to as a(n):
discrete random variable
quantitative data that measures "how many" are___. quantitative data that measure "how much"
discrete, continuous
The purpose of statistical inference is to provide information about the:
population based upon information contained in the sample
the width of the confidence interval is decreased when ___ is increased
sample size
A probability distribution for all possible values of a sample statistic is known as a:
sampling distribution
The probability distribution of all possible values of the sample mean is called the:
sampling distribution of the sample mean
the university street garage has 5 floors. a university official chooses 15 vehicles from each floor
stratified