CBSE Applied Maths (2026-27) Unit V: Descriptive Statistics Weightage: ~10 Marks in Unit

Chapter 11: Correlation Analysis

Analyze relationships between bivariate variables using scatter plots, Karl Pearson's coefficient (r), and Spearman's rank correlation (ρ).

4 Exercises
CBSE Curriculum Aligned
Interactive Quizzes & Solutions

Chapter Exercises & Topics

Select any exercise to access theory notes, formulas, practice drills, and mini tests.

Exercise 11.1 45 mins

Introduction to Bivariate Data

  • Univariate vs. bivariate distributions
  • Positive, negative, zero, linear, and non-linear correlation
  • Applications in finance, science, and economics
Study Exercise Mini Test
Exercise 11.2 45 mins

Scatter Diagram Method

  • Graphical plotting and visual identification of degree/direction of relationship
  • Perfect positive/negative correlation patterns and zero correlation clusters
Study Exercise Mini Test
Exercise 11.3 45 mins

Karl Pearson’s Coefficient of Correlation

  • Assumptions and mathematical limits (-1 <= r <= +1)
  • Computation via direct formula, assumed mean, and step-deviation methods
  • Properties of r (invariance under change of origin and scale)
Study Exercise Mini Test
Exercise 11.4 45 mins

Spearman’s Rank Correlation Coefficient

  • Formula when ranks are distinct: ρ = 1 - 6∑d^2 / (n(n^2-1))
  • Adjustment formula for repeated/tied ranks using correction factor m(m^2-1)/12
Study Exercise Mini Test

Chapter 11 Core Formula Sheet

Quick-glance formula revision for examination and numerical problem-solving:

  • $$Positive: Both variables increase or decrease together$$
  • $$Negative: One variable increases while the other decreases$$
  • $$-1 ≤ r ≤ +1$$
  • $$Points on line sloping upwards from left to right \implies r = +1$$
  • $$Points on line sloping downwards from left to right \implies r = -1$$
  • $$r = ∑(x - \bar{x})(y - \bar{y})\sqrt{∑(x - \bar{x})^2 ∑(y - \bar{y})^2} = Cov(X, Y)σ_x σ_y$$
  • $$r = N∑ xy - ∑ x ∑ y√[N∑ x^2 - (∑ x)^2][N∑ y^2 - (∑ y)^2]$$
  • $$ρ = 1 - 6∑ d_i^2n(n^2 - 1) \quad where d_i = R_x - R_y$$
  • $$Tied Ranks: ρ = 1 - 6[∑ d^2 + ∑ m(m^2-1)12]n(n^2-1)$$
Ch 10: Measures of Dispersion and Percentiles All Chapters Syllabus Ch 12: Regression Analysis