ISDS 1102 Final
If a data set has a standard deviation of 4 units and a mean of 10 units, the coefficient of variation is __
.4
Which of the following graphical depictions are useful for observing the spread of the data for a single variable?
-Stem-and-leaf diagram -Histogram -Polygon
A box plot is constructed using several different values. Which of the following values are included in a box plot?
-The second quartile -The third quartile -The smallest value
The _______ scale categorizes and ranks a qualitative variable.
ordinal
The square root of the average squared deviation of data values from their mean is known as the _______ _______.
standard deviation
List, in order, the process to detect outliers using a box plot.
1. Calculate the interquartile range. 2. Compute the "whiskers" by multiplying the interquartile range by 1.5 3. Draw the "whiskers" (a line). 4. Determine the outliers.
Place the following steps in order to explain how to construct a polygon.
1. Construct a frequency distribution 2. Find the midpoint for each class of the frequency distribution. 3. The midpoints are plotted based on the frequency or relative frequency for the respective class. 4. Neighboring midpoints are connected together by a straight line.
Beginning with the first step, in order, the step to constructing a cumulative frequency distribution.
1. Determine the appropriate number of classes. 2. Determine the class width. 3. Determine the frequency of the observations for each class. 4. Determine the relative frequency for each class. 5. Compute the cumulative relative frequencies.
Measurements that summarize and describe a particular data set are known as _________ statistics.
descriptive
Pat's time in the 1600 meter run placed Pat in the 85th percentile in the school. What percentage of students are faster than Pat?
15
Which of the following scenarios is an example of the interval scale?
A golfers score relative to par.
Sampling is necessary when it is effectively impossible to survey the entire population. Which of the following situations illustrates a situation where sampling, rather than surveying the entire population, is necessary?
A manufacturer of automobile tires wants to determine how long the tread of its tires will last.
Northern University's College of Business wants to determine the average starting salary for last year's graduates of its College of Business. What is the population from which the survey is taken?
All of last year's graduates from Northern's College of Business.
Qualitative Scenario
Diners at a restaurant are asked to rate the food based on the following scale: excellent, good, fair, poor.
Which of the following statements is an accurate statement about a bar chart?
Generally, there is space between the vertical bars.
What is the measure that is primarily used to indicate the central location of a data set?
Mean
Which of the following are measures of the central location of a data set?
Mean, Median, and Mode
In a neighborhood there are six houses listed for sale for the following amounts:$250,000;$275,000;$280,000;$295,000;$515,000. What is the best measure of central location for the price of a house in the neighborhood?
Median
A ________ includes all items of interest in a statistical problem.
Population
When constructing a histogram what values/labels go on the horizontal (x) axis and the vertical (y) axis?
Quantitative class limits on the horizontal axis; frequency or relative frequency on the vertical axis.
When comparing two data sets w/ different units of measurement, what is the relative measure of dispersion?
The coefficient of variation.
Continuous Scenario
The finishing times for running the 100 meter dash.
Which of the following characteristics of interest is a variable?
The number of pizzas ordered from Pizza Hut per day.
Discrete Scenario
The value on a six-sided die
Statistics is used
To make informed decision making in many areas of life when there is access to a data set.
True or False: The arithmetic mean is the primary measure of the central location of a data set.
True
True or False: The geometric mean is the appropriate measure to analyze multi-year investments.
True
One method of graphical presentation for qualitative data is
a bar chart
A significant weakness of the ordinal scale is
an inability to measure differences between the ranked values.
When calculating a percentile, the first step is to arrange the data set in
ascending order (from least to greatest).
To construct a frequency distribution for a qualitative data, the data is split into
categories
The nominal scale of measurement is used to
categorize unranked data
One method of graphical presentation for qualitative data is a bar chart; another graphical presentation for qualitative data is a ____ chart.
pie
The first step to determine the median is to
place the data in numerical order.
A relative frequency distribution for quantitative data identifies
the proportions of observations that occur in each class.
In a given cumulative frequency distribution, the "cumulative frequency" column value for the third class represents
the total number of observations in the first, second, and third classes combined.
Two widely used measures of dispersion are
the variance and the standard deviation.
When a quantitative data set is significantly affected by _______, then the arithmetic mean is usually not a good measure of central location.
outliers
Where a mean is calculated and some observations are given greater importance or value, the mean is known as a _______ mean.
weighted
Stem-and-leaf diagrams can be used to
-Observe individual data points. -Analyze the shape of the data. -Determine how dispersed the data is.
Which of the following are examples of inferential statistics?
-Professor Stats randomly selects 50 female students at State University to estimate the average height of all female students at State University. -A manufacturer of light bulbs randomly selects 100 light bulbs to test the longevity of all light bulbs that the manufacturer produces.
Box plots can be used to
-compare -detect outliers
When a researcher wants to know how many observations of quantitative data fall below a particular class, the researcher must create a
cumulative frequency distribution
The _______ distribution is a way to organize qualitative data into categories and record the actual number of occurrences.
frequency
A ________ mean is the multiplicative average of a data set.
geometric
The _______ mean is the appropriate measure to use when evaluating growth rates.
geometric
The appropriate measure for evaluating investment returns over several years is the
geometric mean
The ______ measures the differences between the largest and smallest values in a data set.
range
A ______ is a subset of a population.
sample
Sampling, rather than surveying an entire population can offer some substantial benefits. Some of those benefits include
saving money and time
A _________ (one word) is a type of graph that allows researchers to examine the the relationship between two variables.
scatterplot
When drawing a graph the vertical axis should generally
should start at the value 0
An ogive is a graph that plots the cumulative frequency, or relative cumulative frequency against the
upper limit of the corresponding class.
A characteristic of interest that differs among various observations is known as a _______.
variable
The average squared distance of data values from their mean is the
variance
A variable that is described verbally rather than numerically is called a ______ variable.
qualitative
A variable that assumes meaningful numerical values is called a(n) _________ variable.
quantitative
Nadia purchased 200 shares of XYZ stock at $20 per share. When the stock decreased in value to $16 share, Nadia purchased 300 more shares of XYZ stock. The weighted average price per share that Nadia paid for XYZ stock is _____.
$17.60
When constructing classes for a frequency distribution of quantitative data, which of the following principles should generally be followed?
-Classes should be the same width. -The classes should be exhaustive. -Classes should be mutually exclusive.
All of the following are examples of cross-sectional data EXCEPT:
-Last month's unemployment rate for various cities in Ohio. **-Quarterly sales for a computer company for the last five years. -The hours worked last week by 50 employees at a factory. -Last years starting salary for 100 recent business graduates at Penn State University.
Which of the following are examples of descriptive statistics?
-The average variation of monthly sales for XYZ Corporations based on XYZ's previous sales data. -A basketball player's shooting percentage -The median price for a house in Normal, Illinois based on a survey of all houses in Normal, Illinois.
A box plot is constructed using several values. Which of the following values from a data set are included in a box plot?
-The largest value -The first quartile
The vertical (y axis) for an ogive can be labeled as
-relative cumulative frequency -cumulative frequency
The interquartile range of a data set
-represent the middle 50% of the data -is calculated by subtracting the first quartile from the third quartile
The process for collecting info about a quantitative issue:
1. Find the appropriate data. 2. Use the appropriate statistical tools. 3. Communicate the numerical info into written info.
Place the steps in order, from beginning to end, to calculate a mean for aggregated data
1. Find the midpoint for each class of grouped data 2. Multiply the midpoint of each class by the number of observations in its class. 3. Sum the products of the midpoints and observations 4. Divide by the total number of observations
The mean absolute deviation for the sample data set: 3,4,5, and 8 is ____
1.5
If the annual returns for a four year period are 8%, -5%, 10%, and 3%, what is the geometric mean rate of return?
3.84%
A pie chart is a segmented circle whose segments when summed equals ____ degrees.
360
Quartiles divide the data into __ equal parts.
4
If the median price for a home is $200,000 then ___% of homes cost less than $200,000
50
The median for the data set: 10,6,4,9,5 is __.
6
Assume that a professor gave an exam to a class of 50 students. The high score was 98 points and the low score was 53 points. The professor wants to create a frequency distribution that is divided into five classes for the exam scores. The approximate class width for the data is __ points but a class width of __ would be easier to read.
9;10
If Fund A has a coefficient of variation of 1.1, and Fund B has a coefficient of variation of .9. Fund __ has the greater relative dispersion.
A
The type of statistics that refers to drawing conclusions about a larger set of data based on a smaller set of data is known as _______ statistics.
inferential
Which scales of data measurement are associated with quantitative data?
interval and ratio
A stem-and-leaf diagram has two parts: The stem and the leaf. The stem consists of the ______ and the leaf consists of the _______.
leftmost digits; last digit
The average of the absolute differences between the values of the data set and the mean is the
mean absolute deviation
The summary measures for grouped data are
only approximate values
When a quantitative data set is significantly affected by _________, then the arithmetic mean is usually not a good measure of central location.
outliers
Generally, the _________ is the best measure of central location when outliers are present.
median
The measure of central location where half the values of the data set lie above this measure and half the values of the data set lie below this measure is known as the _______.
median
The _____ is the measure of central location that also is the most frequently occurring value in the data set.
mode
When summarizing a qualitative data set the _____ is the best measure of central location.
mode
There are several guidelines to follow when constructing graphs that summarize statistical data.. These include which of the following statements?
-Axes that are numerical should be to the appropriate scale. -Axes should be clearly labeled. -The simplest graph that effectively communicates the data should be used.
Nominal Scale Scenarios:
-Noting the racial composition of an undergraduate classroom. -Designating males as 1 and females as 2 to compare gender performance on an aptitude test.
When determining the approximate width of the classes for a frequency distribution of a quantitative data, the difference of what two values is divided by the number of classes?
-The largest value and smallest value.
Statistics can appropriately be used for which of the following?
-To make informed business decisions -To make predictions about tomorrow's weather -To differentiate between logical statistical conclusions and questionable statistical conclusions.
The interval scale of measurement
-allows for the meaningful use of addition and subtraction -is used to measure certain types of quantitative data. -allows for the use of negative values
The rectangles of a histogram
-are drawn with no space, or gaps, between them. -represent grouped data -represent the class width and frequency, or relative frequency, of the respective class.
Polygons
-can be used to determine the shape of the data -are plotted by using the midpoints of the frequency distribution classes.
Histograms can be used to
-determine the shape of the data -observe the spread or the variability of the data
When constructing a bar chart, the vertical axis (the y axis) is labeled with the
-frequency of the data -relative frequency of the data
When working with statistics, you need to find the right or appropriate, data. Which of the following are characteristics of the right data? The data
-lacks misrepresentation -is complete
Place the following list in order, from beginning to end, for the steps required to calculate a particular percentile for a data set.
1. Arrange data set in ascending order. 2. Determine the approximate location. 3. Determine whether the value provided by Lp is an integer. 4. Select or interpolate the appropriate value from the data set.
Place in order, from beginning to end, the steps to calculate the mean absolute deviation.
1. Calculate the arithmetic mean for the data set 2. Find the absolute difference between each data set value and the mean. 3. Sum the absolute differences 4. Divide by the sample (or the population) size
Place the following steps in order, from beginning to end, to create a new box plot
1. Calculate the five-number summary values 2.Plot the five-number summary values in numerical order on a horizontal axis. 3. Draw a box encompassing the first and third quartiles 4. Draw a vertical dashed line inside the box at the median (2nd quartile).
_____ Series data contain values of a characteristic of a subject over time.
Time
One of the primary goals of constructing a frequency distribution for quantitative data is to summarize the data
in a manner that accurately depicts the data as a whole.