Chapter 3: Exploring Quantitative Data

These flashcards cover key concepts related to the exploration and summarization of quantitative data.

Quantitative Data

Data that represents numerical values and can be measured.

Histogram

A graphical display that shows the distribution of a quantitative variable by using bars to represent the frequency of values within specified ranges (bins).

Bins

Equal-width intervals into which the range of a quantitative variable is divided for the purpose of creating a histogram.

Relative Frequency Histogram

A type of histogram that displays the percentage of cases in each bin rather than just the counts, maintaining the area principle.

Stem-and-Leaf Display

A graphical representation that shows the distribution of a quantitative variable while preserving individual data values.

Dotplot

A simple display that places a dot for each case along an axis to represent data points.

Mode

The value or values that appear most frequently in a dataset; a histogram with one peak is unimodal, two peaks is bimodal, and three or more peaks is multimodal.

Symmetric Distribution

A distribution where the left and right sides are mirror images; it has identical left and right tails.

Skewed Distribution

A distribution that is not symmetric; it has one tail longer or fatter than the other.

Outliers

Data values that are significantly different from other observations in a dataset, often appearing far away from the main body of data.

Median

The middle value of a dataset when arranged in ascending order; it divides the dataset into two equal halves.

Interquartile Range (IQR)

A measure of statistical dispersion that is the difference between the upper quartile (Q3) and lower quartile (Q1), representing the middle 50% of data.

Five-Number Summary

A summary of a dataset that includes the minimum, first quartile (Q1), median, third quartile (Q3), and maximum.

Boxplot

A graphical representation of the five-number summary that shows the distribution of a dataset and highlights outliers.

Standard Deviation

A measure of the amount of variation or dispersion in a set of values, indicating how much individual data points deviate from the mean.

Variance

The average of the squared deviations from the mean, a measure of spread that is expressed in squared units.

Quantitative Data Condition

A prerequisite condition ensuring that the data being analyzed is quantitative and suitable for certain statistical methods.