Straighterline Business Stats
Final Exam/270 Q’s and A’s
The main purpose of descriptive statistics is to - - Summarize data in a
useful and informative manner
- Which word is NOT part of the definition of descriptive statistics? - -
Predicting
- A marketing class of 50 students evaluated the instructor using the
following scale: superior, good, average, poor, and inferior. The descriptive
summary showed the following survey results: 2% superior, 8% good, 45%
average, 45% poor, and 0% inferior. - - c. Most students rated the instructor
as poor or average.
- What type of variable is the number of robberies reported in your city? - -
Quantitative
- The Nielsen Ratings break down the number of people watching a
particular television show by age. What level of measurement is age? - -
Ratio
- What level of measurement is a person's "favorite sport"? - - Nominal
- The final rankings of the top 20 NCAA college basketball teams are an
example of which level of measurement? - - Ordinal
- What level of measurement is the Centigrade temperature scale? - -
Interval
- A survey includes a question regarding marital status that has the
following responses: single, married, divorced, separated, or widowed. What
is the scale of measurement for this question? - - Nominal
- A group of women tried five brands of fingernail polish and ranked them
according to preference. What level of measurement is this? - - Ordinal
- Shoe style is an example of what level of measurement? - - Nominal
- When TV advertisements report "2 out of 3 dentists surveyed indicated
they would recommend Brand X toothpaste to their patients," an informed
consumer may question the conclusion because the: - - Advertisement does
not include the total number of dentists surveyed
, - A sample of the paramedical fees charged by clinics revealed these
amounts: $55, $49, $50, $45, $52, and $55. What is the median charge? - -
51.00
- For a data set with an odd number of observations that have been sorted
from smallest to largest values, where is the median located? - - (n + 1)/2
- Assume a student received the following grades for the semester: History,
B; Statistics, A; Spanish, C; and English, C. History and English are 5 credit-
hour courses, Statistics a 4 credit-hour course, and Spanish a 3 credit-hour
course. If 4 grade points are assigned for an A, 3 for a B, and 2 for a C, what
is the weighted mean grade for the semester? - - 2.76
- A disadvantage of using an arithmetic mean to summarize a set of data is
that __________. - - It can be biased by one or two extremely small or large
values
- A survey item asked students to indicate their class in college: freshman,
sophomore, junior, or senior. Which measure(s) of central location would be
appropriate for the data generated by that questionnaire item? - - Mode and
median
- The times (in minutes) that several underwriters took to review
applications for similar insurance coverage are 50, 230, 52, and 57. What is
the median length of time required to review an application? - - 54.5
- For the most recent seven years, the U.S. Department of Education
reported the following number of bachelor's degrees awarded in computer
science: 4,033; 5,652; 6,407; 7,201; 8,719; 11,154; 15,121. What is the
annual arithmetic mean number of degrees awarded? - - About 8,327
- Which of the following measures of dispersion are based on deviations
from the mean? - - All apply
- From the easiest to the hardest "ease of interpretation," rank the measures
of dispersion. - - Range, mean deviation, variance
- The weights of a sample of crates ready for shipment to Moscow, Russia
are (in kilograms): 103, 97, 101, 106, and 103. What is the mean deviation? -
- 2.4 kg
- A sample of assistant professors on the business faculty at state-supported
institutions in Ohio revealed the mean income to be $72,000 for nine
months, with a standard deviation of $3,000. Using Chebyshev's Theorem,
what proportion of the faculty earns more than $66,000, but less than
$78,000? - - At least 75%
, - Based on the Empirical Rule, what percent of the observations will lie
between plus or minus two standard deviations from the mean? - - 95%
- What is the relationship between the variance and the standard deviation?
- - Variance is the square of the standard deviation.
- What statistics are needed to draw a box plot? - - The minimum,
maximum, median, first and third quartiles
- A box plot shows ___________. - - The relative symmetry of a distribution for
a set of data
- A dot plot can be used to show _________________. - - The distribution for a
quantitative variable
- If a student places in the 99th percentile on an exam, she performed better
than 99% of all students who completed the exam. Her performance is
similar to a statement based on a __________. - - Cumulative frequency
distribution
- To locate the percentile for a given observation in a data set, the data
must be ___________. - - Sorted and listed from the minimum to the
maximum values
- The test scores for a class of 147 students are computed. What is the
location of the test score associated with the third quartile? - - 111
- In a distribution, the second quartile corresponds with the __________. - -
Median
- A dot plot shows ____________. - - The general shape of a distribution
- The range of the coefficient of skewness is ____________. - - Both positive
and negative values
- A sample of experienced typists revealed that their mean typing speed is
87 words per minute and the median typing speed is 73 words per minute.
The standard deviation of typing speed is 16.9 words per minute. What is the
Pearson coefficient of skewness? - - +2.5
- If the coefficient of skewness is equal to zero, the shape of the distribution
is __________. - - Symmetric
- A large oil company is studying the number of gallons of gasoline
purchased per customer at self-service pumps. The mean number of gallons