Definition

Noun: A graphical representation of data using bars of different heights. In a histogram, the bars are placed next to each other to show the frequency distribution of numerical data. The height of each bar corresponds to the frequency or count of observations within a specific range (called a "bin" or "class interval").

Usage

A histogram is used in statistics to visualize the distribution of a dataset. It helps to show the central tendency, dispersion, and shape of the data's distribution (e.g., whether it is symmetric, skewed, etc.). It is specifically for continuous or interval data where the bars represent ranges of values.

Examples

• The researcher created a histogram to display the distribution of test scores for the class.
• By examining the histogram, we could see that most of the data was clustered around the mean.
• A histogram of daily temperatures revealed a bell-shaped curve.

Advanced Usage

• Bimodal Histogram: A histogram with two distinct peaks, suggesting the data may come from two different groups or processes.
  • The histogram of customer heights was bimodal, likely reflecting the mix of adult men and women in the sample.
• Skewed Histogram: A histogram where the data is not symmetrical, with one tail longer than the other.
  • The histogram of household income was right-skewed, with a few very high incomes pulling the mean upward.

Variants and Related Words

• Histogram Equalization (n): An image processing technique that improves contrast by adjusting the intensity distribution in a histogram.
• Frequency Polygon (n): A line graph created by connecting the midpoints of the tops of the bars in a histogram. It represents the same frequency distribution.

Synonyms

• Frequency Distribution Chart: A more descriptive term for a histogram.
• Bar Graph (for continuous data): While a bar graph is similar, it is typically used for categorical data with spaces between bars, whereas a histogram is for continuous data with adjacent bars.

Key Distinction (Not an Idiom, but a Critical Clarification)

• Histogram vs. Bar Chart: A common point of confusion. A histogram represents the frequency distribution of (e.g., ages, weights, scores), and its bars are adjacent. A bar chart represents (e.g., types of fruit, countries), and its bars are separated by gaps.

Noun

1. a bar chart representing a frequency distribution; heights of the bars represent observed frequencies