Ch. 2 Tabular and Graphical Methods

A new dining plan was implemented in a residence hall at State University. Residents were asked to assess the new plan and give a grade of A, B, C ,D or F to the new dining plan. Of 480 residents, 234 gave a grade of B, 85 a grade C, 13 a grade of D and 4 a grade of F. The proportion of A grade is _____.

0.30 [480-(234+85+13+4)=144. Then 144/480=0.30

Assume that a professor gives an exam to a class of 50 students. The high score is 98 points and the low score is 48 points. The professor wants to create a frequency distribution that is divided into five classes for that exam scores. The class width for the data is approximately ____ points.

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A new dining plan was implemented in a residence hall at State University. Residents were asked to assess the new plan and give a grade of A, B, C, D, or F to the new dining plan. Of 480 residents, 234 gave a grade of B, 85 a grade of C, 13 a grade of D, and 4 a grade of F. The number of A grads is ____.

144 [480-(234+85+13+4) = 144

One of the primary goals when constructing a frequency distribution of quantitative data is to summarize the data in a manner that ____.

accurately depicts the data as a whole

A(n) ______ depicts the frequency or the relative frequency for each category of a qualitative variable as a series of horizontal or vertical bars, the lengths of which are proportional to the values that are to be depicted.

bar chart

When a researcher examine quantitative data and wants to know the number of observations that fall below the upper limit of a particular class, the researcher is BEST served by creating a ______.

cumulative frequency distribution.

In order to summarize qualitative data, a useful tool is a (n) ____.

frequency distribution

In descriptive statistics, a polygon is best described as a _____.

graph that connects the midpoints of each class and its associated frequency or relative frequency.

A steam-and-leaf diagram has two parts: The seam and the leaf. The steam consists of the _____ and the leaf consists of the _____.

leftmost digits, last digit

Steam-and-leaf diagrams can be used to

observe individual data points analyze the shape of the data determine how dispersed the data are

A (n) _____ is a segmented circle whose segments portray the relative frequencies of the categories of some qualitative variable.

pie chart

One method of graphical presentation for qualitative data is a (n) ______.

pie chart

A cumulative relative frequency distribution for quantitative data identifies the ____.

proportion of observations that fall below the upper limit of each class.

A relative frequency distribution for quantitative data identifies the _____.

proportion of observations that occur in each class.

What graphical tool is best used to display the relative frequency of grouped, quantitative data?

Histogram

Which of the following graphical depictions is useful for observing the spread of the data for a single variable?

Histogram

Which of the following BEST describes a frequency distribution for qualitative data?

It groups data into categories, and records the number of observations in each category.

Which of the following graphical depictions displays cumulatve data?

Ogive

Which of the following graphical depictions are useful to observe the shape (distribution) of a data set for a single variable?

Polygon Stem-and-leaf diagram Histogram

When constructing a histogram, what values/labels go on the horizontal (x) axis and the vertical (y) axes?

Quantitative class limits on the horizontal axis; frequency or relative frequency on the vertical axis.

Which of the following graphical depictions allows you to examine the relationship between two variables?

Scatterplot

Which of the following graphical depictions allows you to examine the relationships between two variables?

Scatterplot

When constructing a graph, which of the following statements is MOST accurate?

The simplest graph should be used for a given set of data.

The accompanying frequency distribution summarizes the colors of cars in a mall parking lot. There are ____ cars in the parking lot. Color - Frequency Black - 12 Blue - 4 Silver - 6 White - 12 Other - 16

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