Frequency Distribution and Histogram

  • Data is the raw material while Information derived from this data is finished product 
  • Data represents numbers and facts in the format in which was collected from the source
  • Data can be Qualitative or Quantitative:
    • Qualitative like 
      • Food is tasty, Movie was worth the money, etc.
      • It cannot be computed
    • Quantitative like
      • Numeric data
        • Discreet - Whole number
        • Continuous - Real or Float number  
  • Data can also be Categorical or Discreet:


  • Information is derived out of this data to help decision making by the stakeholders

Frequency Distribution
  • Frequency Distribution is a table in which raw data is arranged into classes and corresponding frequencies.
  • Here raw data is classified into information
  • Most widely used data reduction technique in descriptive statistics
  • Frequency Distribution can be visually represented using Histogram

Histogram
  • Histogram is a visual representation of Frequency Distribution in which the X-axis is represents the classes while the Y-axis represents the frequencies 
  • Histogram can be also called as Frequency Histogram
  • In practicality, Histogram can be used to 
    • Assess the material strength
    • Estimate process capability
    • Indicate the need for corrective measures
    • Measure effects of corrective measure taken
    • Estimate Machine Capability
    • Compare operators, vendors, materials or product

  • Grouping of data is called Binning and each group is called Bin 
 

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