Index Ideas

Robust index design

The case for sensitivity-aware methodologies

Andreas Schroeder

Head of Index Research and Design, EMEA

Tom Chan

Senior Research Analyst, Research and Analytics

Ely Klepfish

Manager, Research, FTSE Russell Index Research and Design - EMEA

Key takeaways:

  • Index sensitivity to data errors varies among data inputs, in particular sustainability data
  • Different index construction methodologies exhibit different sensitivity to data errors, underscoring the importance of methodology selection
  • Understanding the sensitivity to data errors is key to robust index construction

Points of differentiation:

  • We propose an original and efficient method of input-sensitivity analysis
  • We introduce a new and efficient methodology for assessing how index performance responds to variations in input data
  • The results are intuitive and expressed in terms of turnover/costs to correct data errors
  • Inclusion of data-sensitivity analysis facilitates enhanced index design

What does our research mean for investors?

  • We examine our index design to strike a balance between specificity to the signal vs. robustness against noise. This approach helps support more stable, transparent, and investable benchmarks that align with institutional performance and risk objectives
  • With this tool, choosing the most suitable methodology can be straightforward and intuitive for investors