W - 4: SOLVE & INTERPRET DECILES(GROUPED DATA)

• Grouped data

  Data formed by aggregating individual observations of a variable into groups, so that a frequency distribution of these groups serves as a convenient means of summarizing or analyzing the data
• Formula for Decile

  1. Dk class = kn/10

  2. Dk = LB + (kn/10 - <cfb)/fDk * i

  3. LB = lower boundary of the Dk class

  4. n = total frequency

  5. <cfb = less than cumulative frequency before the Dk class

  6. fDk = frequency of the Dk class

  7. i = size of the class interval

  8. k = nth decile
• Grouped Data Table

  • Class interval Scores (i)
  • Frequency (f)
  • LB (lower boundary)
  • <cf (less than cumulative frequency)
• Solving

  1. Step 1: Create additional column for the lower boundary and less than cumulative frequency

  2. Step 2: Fill in the table by identifying the lower boundary and less than cumulative frequency

  3. Step 3: Determine the Dk class

  4. Step 4: Apply the formula for DECILE to solve the decile value