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Scatter Diagram Generator

Analyze Relationships & Correlations Between Variables

Scatter Diagram Generator

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Temperature vs Pressure Relationship

10.019.028.037.046.055.020.026.432.839.245.652.0Temperature (°C)Pressure (bar)

Legend

Data Points
n = 10
Trend Line
r = 0.98
StrengthStrong

Correlation Analysis

Correlation (r): 0.9828

R-squared: 0.9659

Strength: Very Strong

Type: Positive

Linear Regression

Slope: 0.6945

Intercept: 13.7273

Equation: y = 0.69x + 13.73

Statistical Significance

Sample Size: 10

Significance: Not significant

Variance Explained: 96.6%

📊 Correlation Interpretation

Correlation Strength: Very strong relationship between variables

Direction: Positive correlation - as X increases, Y tends to increase

Practical Application: Strong predictive model - suitable for forecasting

📊 About Scatter Diagrams

Scatter diagrams (scatter plots) are graphical tools used to investigate the relationship between two variables and identify potential correlations.

Key Features

  • • X-axis: Independent variable
  • • Y-axis: Dependent variable
  • • Each point represents one data pair
  • • Pattern reveals relationship strength

Applications

  • • Process optimization
  • • Root cause analysis
  • • Predictive modeling
  • • Quality improvement

🔗 Correlation Types

Positive Correlation

As X increases, Y increases. Points form an upward trend.

Example: Temperature vs. Ice cream sales

Negative Correlation

As X increases, Y decreases. Points form a downward trend.

Example: Price vs. Demand

No Correlation

No apparent relationship. Points are randomly scattered.

Example: Shoe size vs. Intelligence

🏭 Practical Example

Scenario: Manufacturing Process Optimization

A chemical plant wants to optimize reaction temperature to maximize product yield:

Data Collection:
  • • X-variable: Reaction temperature (°C)
  • • Y-variable: Product yield (%)
  • • Sample size: 30 production batches
  • • Time period: 3 months of operation
Analysis Results:
  • • Strong positive correlation (r = 0.85)
  • • Optimal temperature range: 180-190°C
  • • Expected yield increase: 8-12%
  • • Action: Standardize temperature control

📏 Correlation Strength Guide

Correlation Coefficient (r)

±0.90 to ±1.00:Very Strong
±0.70 to ±0.89:Strong
±0.50 to ±0.69:Moderate
±0.30 to ±0.49:Weak
±0.00 to ±0.29:Very Weak

Interpretation Tips

  • Causation ≠ Correlation: Strong correlation doesn't prove causation
  • Outliers: Single extreme points can skew results
  • Sample Size: Larger samples give more reliable results
  • Non-linear: Some relationships aren't straight lines
  • Context: Always consider the practical significance

⚠️ Common Pitfalls

Spurious Correlation

Two variables may correlate due to coincidence or a hidden third variable. Always verify with domain knowledge.

Range Restriction

Limited data ranges can hide or artificially reduce correlations. Collect data across full operational ranges.

Confounding Variables

External factors may influence both variables. Control or account for these in your analysis.