Chapter 1

A stem-and-leaf plot basically

· A frequency tally · A tool which uses the digits in each number to create stems and leaves · A toll used in exploratory data analysis

Cumulative frequency distribution show the

· Accumulated counts up to and including the current bin as the bin limits increase

There are several guidelines that once should follow when creating graphs. Which of the following describes these guidelines

· Aces should be clearly labeled · Axes that are numerical should be to the appropriate scale · Novelty graphs such as pyramids charts introduce ambiguity

Stem-and-leaf displays can be used to

· Analyze the small samples of integer data · Determine central tendency and dispersion

Polygons

· Are plotted by using the midpoints of the frequency distribution classes · Can be used to determine the shape of the data

One of the primary goals of contracting a frequency distribution for quantitative data is to summarize the date

· By showing frequency of values that lie within a class or bin

Place the following steps in order to explain how to construct a polygon

· Construct a frequency distribution · Find the midpoint for each interval of the frequency distribution · The midpoint are plotted based on the frequency or relative frequency for the respective class · Neighboring midpoints are connected together by a straight line

An ogive is useful for

· Finding percentiles · Comparing the shape of known distribution.

Based on the distribution below, the proportion (decimal form) of test scores that are 150or less is?

8

True or false: A dot plot displays individual values of qualitative data

False

Which type of data cannot be sorted?

Nominal

If the data were collected from a random sample, we must allow for _____ error.

sampling

Histograms can be used to

· Observe the spread or the variability of the data · Determine the shape of the data

Based on the pictured histogram the distribution of the data can be best be described as

· Positively skewed, or skewed right

When constructing a histogram that values/labels go on the horizontal (x) axis and the vertical (y) axis

· Quantitative bin limits on the horizontal axis; frequency or relative frequency on the vertical axis

When a researcher wants to know the proportion of all observations that fall within a particular bin they would need the

· Relative frequency distribution

Match the term with the histogram description Symmetric=> Right skewed=> Left skewed=>

· Symmetric=> A histogram with evenly distributed tails · Right skewed=> A histogram with a right tail that is longer than the left tail · Left skewed=> A histogram with a left tail that is longer than a right tail

When determining the approximate width of the bins for a frequency distribution of quantitative data, the difference of what two values is divided by the number of bins?

· The maximum value and the minimum value

A relative frequency distribution for quantitative data identifies

· The proportion of observations that occur in each bin.

Identify the problems with the pictured graph

· There is no 0 value on the vertical axis · The time range needs to be specified. The vertical axis limit is too high

Dot plot can show which features of a data set?

· Variability · Center · Shape

Sorting data is helpful because

· We can see the range of values · We can see the frequency of each data value