Basis of Statistical Calculations in Classified Data
In statistical calculations on classified (grouped) data, which values are used instead of the actual values of observations?
- The actual values of each observation
- The upper class limits
- The lower class limits
- The class mark (mid-point) values — Correct Answer
Explanation:
Correct Answer Explanation
In a frequency distribution, further statistical calculations are based only on the class mark (mid-point) values, not on the actual values of observations.
Key Points:
- Once raw data is grouped into classes, individual observations lose significance.
- All values in a class are assumed to be equal to the class mark.
- Example: Class 20–30 contains 6 observations (25, 25, 20, 22, 25, 28). In calculations, all are treated as 25 (the class mark).
- This is the 'Loss of Information' inherent in classification.
📚 About this Topic — CH-3: Organisation of Data
This multiple choice question is from CH-3: Organisation of Data, NCERT Books, Statistics for Economics. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from CH-3: Organisation of Data to strengthen your preparation.