A watershed is a complex network of tributaries all connecting to form a river. This network of stream segments and their connections can be seen as a kind of graph. This presentation uses Neo4j to analyze water quality data from the Rouge River collected by the volunteers from the Friends of the Rouge to find sections of the system that may be more susceptible to pollution flowing into the river.

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© 2022 Neo4j, Inc. All rights reserved.
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GraphSummit Detroit

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© 2022 Neo4j, Inc. All rights reserved.
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May 11, 2023
David J Corliss, PhD
Graph Analytics in Public
Service: Analyzing Water
Quality in Rivers and Streams

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Outline
• Introduction: Data For Good
• Applications in Graph Analytics
• A Watershed as a Graph
• Rouge River Graph Analysis
• Conclusions

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Introduction: Data for Good

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Statistical Volunteering:
Statisticians, Data
Scientists, and others…
…using our analytic
skills…
…to help people and a
make better world
Data For Good
…on volunteer projects…

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Why
Volunteer
?
• Learn New Analytic Methods
• Network, Get Help, Be A Mentor
• Career Development
• Make a Difference!

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Applications in Graph Analytics

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Relational vs. Graph Database
● Stores information in columns
and rows that are referred to
by a primary key
● Compute-heavy, memory
intensive and have an
exponential cost if many
relations are involved with
complex joins
Relational Database
● Stores information in nodes with
relationships between them that
are organized by type and
direction
● More flexibility because the
database model allows one to add
new nodes and relationships
without compromising existing
network
● Highly efficient queries
Graph Database

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Graph Analytics: Many Applications
Plant Floor
Work Flow
Computer
Network
Optimization
HR:
Organizational
Efficiencies
School / Training Curricula

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Analysis of a Watershed as a Graph

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Analysis of a Watershed as a Graph
Why A Graph Database for Stream Analysis?
Looking at individual data collection sites and their
characteristics could be done with a relational database
However, a graph database is needed to capture the
relationships between them
A graph database allows for easy traversal between nodes,
describing quality changes as the water flows downstream
Conclusion: A graph database supports a better description

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Analysis of a Watershed as a Graph
Map: Friends of the Rouge

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Analysis of a Watershed as a Graph
Map: Friends of the Rouge Plot: Peace-Work

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Analysis of a Watershed as a Graph

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Rouge River Graph Analysis

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Identifying High Risk Stream Segments

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Summary

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• Six high-risk stream segments in the Rouge River watershed
identified for further study
• Graph Analytics can be considered in many different
situations where a set of objects are connected by actions
• Think about opportunities where data science can be used
for community service projects
Summary

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© 2022 Neo4j, Inc. All rights reserved.
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