An Obituary for Bar Charts Cross-Category Visualization & Interpretation Tools to Handle the Increasing Complexity in LCA Results Christoph Koffler, PhD - PE INTERNATIONAL
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An Obituary for Bar Charts
visualization
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interpretation
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An Obituary for Bar Charts
visualization
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An Obituary for Bar Charts Charts galore!
median across 6 random PE LCA reports
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Not very readable...
9/23/2013 http://scriptshadow.blogspot.com/2011/12/article-10-ways-to-bore-hell-out-of.html
An Obituary for Bar Charts
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An Obituary for Bar Charts Hierarchical structure in LCA is complex‌ LCIA results
AP
Manufacturing
Inbound transport
Raw materials
EP
GWP
Processing
Packaging
Waste treatment
Resource Use
ODP
Primary packaging
POCP
Use
Secondary packaging
End-of-Life
Distribution
Waste treatment
Transport
Plastics
Truck
Electricity
Recycling
Cardboard
Cardboard
Energy use
Truck
Recycling
Steel
Rail
Heat
Landfilling
Plastic
Plastic
Consumables
Rail
Landfill
Water
Incineration
Wood
Wood
Maintenance
Aluminum
Incineration
etc.
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An Obituary for Bar Charts ‌ and not easily displayed in bar charts.
x no. of impacts!
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An Obituary for Bar Charts Efficient Visualization of Quantitative Information • Edward Tufte – Yale Professor Emeritus of Political Science, Statistics, and Computer Science
• Multiple books on visual display of information • Promotes using one ‘super-chart’: • • • •
‘high-resolution data dump’ equivalent to 50-250 slides leverage the mbit/s capacity of the eye-brain-system information overload always a design failure
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An Obituary for Bar Charts ‘Treemaps’? • developed by Ben Shneiderman at the Department of Computer Graphics, University of Maryland
• looking for a way to effectively visualize hard drive utilization across complex folder structures
• first published in 1992 • ‘treemap’ describes the notion of turning a tree into a planar, spacefilling map http://www.cs.umd.edu/hcil/treemap-history/index.shtml
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Exemplary PCF Contribution Analysis Based on 44 data points - not actual LCA results
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Exemplary USEtox (HTPC) Contribution Analysis Based on 1,371 data points - not actual LCA results
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Exemplary Endpoint (ReCiPe H) Contribution Analysis Based on 500 data points - not actual LCA results
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An Obituary for Bar Charts Conclusions visualization • Treemap great tool for contribution analysis across complex structures • Can replace multiple bar charts and/or tables • LCA model needs to be structured accordingly to minimize effort
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An Obituary for Bar Charts
interpretation
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An Obituary for Bar Charts Interpretation more and more challenging • 4 disposal routes • 2 additional scenarios • 9 impact categories • with and without credits
108 data points weighting not allowed Montalbo et al (2013): Flick It or Ship It? A Comparative Life Cycle Assessment of Cigarette Waste Disposal Routes. LCA XIII, Oct 1-3, 2013, Orlando, FL
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An Obituary for Bar Charts Quo vadis?
Weighting not permitted
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Increasing complexity
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An Obituary for Bar Charts Rank scoring = weighting? • ISO 14044, section 4.4.3.1: “converting and possibly aggregating indicator results across impact categories using numerical factors based on valuechoices”
• Borda count • stems from voting theory • developed by Jean-Charles de Borda in 1770 • used to establish the MVP in MLB, the Heisman trophy winner, and to rank NCAA teams
• used in various elections at US colleges & universities
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An Obituary for Bar Charts Rank scoring ≠ weighting
• voters rank their candidates use category indicator results per impact • each rank associated with a certain score • the candidate with the most number of points wins
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An Obituary for Bar Charts Borda count LCA example
Scenarios that differed by less than 10% in a non-toxicity impact category and by less than the published thresholds for toxicity impacts were assigned the same rank. Montalbo et al (2013): Flick It or Ship It? A Comparative Life Cycle Assessment of Cigarette Waste Disposal Routes. LCA XIII, Oct 1-3, 2013, Orlando, FL
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An Obituary for Bar Charts Borda count LCA example
Scenarios that differed by less than 10% in a non-toxicity impact category and by less than the published thresholds for toxicity impacts were assigned the same rank. Montalbo et al (2013): Flick It or Ship It? A Comparative Life Cycle Assessment of Cigarette Waste Disposal Routes. LCA XIII, Oct 1-3, 2013, Orlando, FL
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An Obituary for Bar Charts Rank frequency analysis conclusions PROS:
• Enables cross-category evaluation • Does not perform weighting of indicator results as described by ISO (e.g., normalized category indicator result x weighting factor)
• Can inform, but not replace ‘human’ decision making CONS:
• Intrinsically assumes equal relevance of the impact categories for the overall conclusion
• Does not account for the difference between impact results beyond the defined thresholds
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An Obituary for Bar Charts
Thank you very much. c.koffler@pe-international.com
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ANNEX
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Resources Treemap • http://www.cs.umd.edu/hcil/treemap-history/index.shtml • http://www.cs.umd.edu/hcil/treemap/index.shtml • http://www-958.ibm.com/software/analytics/manyeyes/ • https://developers.google.com/chart/interactive/docs/gallery/treemap • http://www.tree-mapper.com/ • http://sparklines-excel.blogspot.com/
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Resources Borda count • http://en.wikipedia.org/wiki/Borda_count • http://en.wikipedia.org/wiki/Voting_system • http://www.deborda.org/
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