Statistics Ch.2

Which of the following are example(s) of qualitative data? Select all that apply.

- Brand of jeans - Cell phone service provider - Major of a student

Which of the following is are true about class widths? Select all that apply.

- Class widths should be the same for each interval. - Class widths should be easy to recognize and interpret. - Each value should fit into only one class.

Stem-and-leaf diagrams can be used to (Select all that apply)

- Determine how dispersed the data are. - Analyze the shape of the data. - Observe individual data points.

Which of the following are example(s) of quantitative data?

- Lifetime of a light bulb - Miles per gallon

A pie chart is a segmented circle whose segments add up to ______ degrees.

360

With respect to a bar chart, which of the following statements is MOST accurate?

A bar chart is a useful graphical tool for qualitative data.

A ______ is a way to organize qualitative data into categories and record the number of observations in each category.

Frequency Distribution

In order to approximate the class width for a frequency distribution of quantitative data, we calculate:

Largest Value - Smallest Value / Number of Classes

Histograms can be used for all of the following EXCEPT to

Observe individual data points.

Which of the following is NOT true about the total number of classes in a frequency distribution?

The number of classes should be between 15 and 20.

The frequency for a class such as '12 up to 25' is

The number of data points that are at least 12, but less than 25.

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

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

Which of the following are example(s) of quantitative data?

- Temperature of coffee - Wait time at a doctor

Which of the following levels of measurement are typical of qualitative data? Select all that apply.

- Nominal - Ordinal

A scatterplot is a type of graph that allows researchers to examine the relationship between two variables. It helps to identify

- Positive relationships. - Nonlinear relationships. - Negative relationships. - Linear relationships.

Which of the following is true regarding the shape of a histogram?

- Positively skewed distributions have a cluster of tall bars with several bars to the right that are much shorter. - Negatively skewed distributions have a cluster of tall bars with several bars to the left that are much shorter.

Which of the following statements is LEAST accurate?

- The height of each rectangle represents cumulative frequency or cumulative relative frequency.

Histograms and polygons are graphical depictions that display which of the following? Select all that apply.

- The location where the data clusters. - The spread in a set of data. - The shape of a set of data.

Which of the following are true about bar charts? Select all that apply.

- They can display relative frequencies. - The bars don't touch. - They can display frequencies.

One of the primary goals when constructing a frequency distribution for 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

One method of graphical presentation for qualitative data is a _____.

Bar Chart

When a researcher examines 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

A category's relative frequency is found by

Dividing its frequency by the number of observations.

The sum of the frequencies for a relative frequency distribution should always be

Equal to 1

A useful tool for summarizing qualitative data is is a(n) ______.

Frequency Distribution

For quantitative data, a ______ groups data into classes and records the number of observations that falls into each class.

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.

There are several guidelines to follow when constructing graphs that summarize statistical data. Which of the following statements is LEAST accurate?

Graphs should have a lot of adornments.

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

Histogram

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; digit to the right of the stem

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.

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.

Each piece of a pie chart represents a category's

Relative Frequency

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

Scatter Plot

When constructing classes for a frequency distribution for quantitative data, which of the following statements is LEAST accurate?

The number of classes should equal the number of observations.

The cumulative frequency for the last class should always equal

The number of observations

Which one of the following is true about ogives?

The only difference in ogives that plot cumulative frequencies and those that plot cumulative relative frequencies is the scale on the y-axis.

An ogive is a graph that plots the cumulative frequency, or cumulative relative frequency, at the

Upper limit of the corresponding class.

A polygon uses

Uses a continuous line to represent the shape of the distribution of a data set.

When two variables exhibit a negative relationship,

Y decreases as X increases.