Introduction
This analysis explores the drivers of employee attrition using HR
data including:
- Satisfaction levels
- Performance evaluations
- Number of projects
- Working hours
- Tenure
- Other workplace factors
Exploratory Data Analysis - Numerical Variables
Key observations:
- Satisfaction shows a trimodal distribution
- Last evaluation scores are slightly right-skewed
- Project count clusters around 3-4 projects
- Monthly hours show peaks at ~150 and ~250 hours
Exploratory Data Analysis - Categorical Variables
Key observations:
- Sales and technical departments have highest employee counts
- Most employees are in low salary bracket
- Low incidence of work accidents (only 14% had accidents)
- Very few promotions in last 5 years (less than 2% promoted)
Attrition Analysis - Satisfaction and Evaluation
T-Test Results:
Satisfaction Level:
- Mean difference: 0.25 (Stayed = 0.67, Left = 0.42)
- t-value = -33.259, p < 0.001
- Conclusion: Significantly lower satisfaction among those who
left
- Employees who stay are 50% more satisfied
Last Evaluation:
- Mean difference: 0.02 (Stayed = 0.71, Left = 0.73)
- t-value = 0.127, p > 0.001
- Conclusion: There is no difference in last evaluation between those
that stay vs. those that left
Attrition Analysis - Workload
T-Test Results:
Number of Projects:
- Mean difference: -0.46 (Stayed = 3.79, Left = 4.25)
- t-value = 2.006 , p > 0.001
- Conclusion: Number of projects has no effect on employee status
Monthly Hours:
- Mean difference: -18.21 (Stayed = 199.31, Left = 217.52)
- t-value = 5.869, p < 0.001
- Conclusion: Significantly longer hours worked by those who left
(+3%)
Correlation Analysis

Key Correlation Findings:
Strongest Positive Correlations:
- Projects & Hours: r = 0.53 (p < 0.001)
- Evaluation & Hours: r = 0.42 (p < 0.001)
- Projects & Evaluation: r = 0.45 (p < 0.001)
Strongest Negative Correlations:
- Time at Company & Satisfaction: r = -0.14 (p < 0.001)
- Satisfaction & Projects: r = -0.15 (p < 0.001)
Department and Salary Analysis
Chi-Square Test Results:
Department & Attrition:
- χ² = 15.878, df = 9, p > 0.001
- Conclusion: No significant relationship between department and
attrition
- Sales and technical departments show highest attrition rates
Salary Level & Attrition:
- χ² = 106.5, df = 2, p < 0.001
- Conclusion: Significant relationship between salary and
attrition
- Lower salary levels associated with higher attrition
Additional Categorical Analysis
Chi-Square Test Results:
Work Accidents & Attrition:
- χ² = 173.76, df = 1, p < 0.001
- Conclusion: Significant relationship between accidents and
attrition
- Lower attrition among those who had accidents
Promotions & Attrition:
- χ² = 31.295, df = 1, p < 0.001
- Conclusion: Significant relationship between promotions and
attrition
- Lower attrition among those who received promotions
Key Findings
Satisfaction Level
- Strong predictor of attrition
- Employees who left had significantly lower satisfaction
Workload
- Much higher number of projects associated with attrition
- Longer working hours among those who left
Career Growth
- Very low promotion rates overall
- Salary level significantly associated with attrition
Departmental Differences
- No significant variation in attrition across departments
- Sales and technical departments show higher attrition
Recommendations
Workload Management
- Monitor and balance project assignments
- Address excessive working hours
Career Development
- Increase promotion opportunities
- Develop clear career progression paths
Department-Specific Initiatives
- Focus retention efforts on high-risk departments
- Address department-specific satisfaction drivers
Satisfaction Monitoring
- Regular satisfaction surveys
- Early intervention for declining satisfaction