Correlation Coefficient Formula:
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The correlation coefficient (r) measures the strength and direction of the linear relationship between two variables. It ranges from -1 to +1, where +1 indicates perfect positive correlation, -1 indicates perfect negative correlation, and 0 indicates no linear correlation.
The calculator uses the Pearson correlation coefficient formula:
Where:
Explanation: The formula calculates how much two variables change together relative to how much they vary individually.
Details: Correlation analysis is fundamental in statistics, research, and data science for identifying relationships between variables, though it does not imply causation.
Tips: Enter comma-separated values for both X and Y variables. Ensure both lists have the same number of values (minimum 2 pairs). The calculator will compute the correlation coefficient r.
Q1: What does the correlation coefficient value mean?
A: Values close to +1 indicate strong positive correlation, close to -1 indicate strong negative correlation, and near 0 indicate weak or no linear relationship.
Q2: Can correlation prove causation?
A: No, correlation only measures association. Causation requires additional evidence from controlled experiments or theoretical justification.
Q3: What's the difference between correlation and regression?
A: Correlation measures the strength of relationship, while regression models the relationship to make predictions.
Q4: When is correlation most useful?
A: When examining linear relationships between continuous variables and when assumptions of normality and linearity are met.
Q5: What are limitations of correlation analysis?
A: It only measures linear relationships, can be influenced by outliers, and doesn't account for confounding variables.