Frequency Distribution Calculator

Create frequency tables, cumulative distributions, and statistical summaries from your data

Data Input

Enter numeric values. Empty fields will be ignored.

Example: Test Scores Analysis

Sample Data

Student Test Scores: 85, 92, 78, 85, 90, 88, 85, 95, 82, 87

Sample Size: 10 students

Frequency Distribution

ScoreFrequencyPercentage
78110%
82110%
85330%
87110%
88110%
90110%
92110%
95110%

Analysis

Mean: 86.7 points

Median: 86.5 points

Mode: 85 (appears 3 times)

Interpretation: Most students scored around 85-90, with 85 being the most common score

Distribution Types

U

Ungrouped Data

Each unique value gets its own frequency count

Best for discrete data with few unique values

G

Grouped Data

Values are grouped into intervals (classes)

Best for continuous data or large datasets

C

Cumulative Frequency

Running total of frequencies

Shows total count up to each value

Key Concepts

FrequencyCount of occurrences
Relative FrequencyFrequency ÷ Total
Cumulative FrequencyRunning total
Class WidthInterval size
Class Midpoint(Lower + Upper) ÷ 2

Analysis Tips

Use ungrouped data for small datasets

Group data when you have many unique values

Mode shows the most common value

Cumulative frequency helps find percentiles

Understanding Frequency Distribution

What is Frequency Distribution?

Frequency distribution is a statistical method that shows how often each value appears in a dataset. It organizes data into a table or chart that displays the frequency (count) of each value or group of values, making it easier to understand the pattern and distribution of your data.

Types of Frequency Distribution

  • Ungrouped: Each unique value has its own frequency count
  • Grouped: Data is organized into class intervals
  • Cumulative: Shows running totals of frequencies
  • Relative: Shows frequencies as percentages

Key Statistical Measures

Measures of Central Tendency:

  • Mean: Average of all values
  • Median: Middle value when sorted
  • Mode: Most frequently occurring value

Measures of Dispersion:

  • Range: Difference between max and min
  • Variance: Average squared deviation from mean
  • Standard Deviation: Square root of variance

Frequency Formulas:

  • Relative Frequency: f/n
  • Percentage: (f/n) × 100
  • Cumulative Frequency: ∑f up to that point

Applications and Uses

Academic Research

Analyzing test scores, survey responses, and experimental data to understand distributions and patterns.

Business Analytics

Examining sales data, customer demographics, and performance metrics for business insights.

Quality Control

Monitoring manufacturing processes, tracking defect rates, and ensuring product consistency.

Best Practices

  • • Choose appropriate class intervals for grouped data (typically 5-20 classes)
  • • Ensure class intervals are equal width when possible
  • • Consider the data type when deciding between grouped and ungrouped distribution
  • • Use cumulative frequency to find percentiles and quartiles
  • • Visualize data with histograms or bar charts for better understanding