Part 1: Identity Resolution: Navigating the Landscape for Marketing in the Modern World

Part 1: Navigating the Identity Resolution Landscape for Marketing in the Modern World - The critical elements to grasp the concept of identity resolution. The quest for a "single view of the customer"

Part 1: Identity Resolution: Navigating the Landscape for Marketing in the Modern World
Photo by Girl with red hat / Unsplash


In the labyrinthine world of digital marketing, one of the most elusive yet critical elements to grasp is the concept of identity resolution. The quest for a "single view of the customer" often feels like the marketing equivalent of the Holy Grail. We have discussed it now for nearly 30 years across the Martech industry. But why is identity resolution so important, and what challenges do marketers often face when implementing it? This is the first of a set of short articles to help summarize many of the points other product marketers and product managers try to complicate in their writings - they are less comprehensive than some other articles and summarize to help guide you to those more detailed points.

Importance of Identity Resolution: A Seamless Customer Experience

In today's competitive marketplace, customer experience is the linchpin that often determines a business's success or failure. With the proliferation of digital touchpoints—mobile apps, social media, or e-commerce platforms—consumers interact with brands in myriad ways. The challenge lies in unifying these fragmented interactions into a cohesive customer journey. That's where identity resolution steps in, supporting a seamless and personalized experience across various channels and platforms.

The concept of identity resolution isn't merely about avoiding duplicate profiles or streamlining data; it's a strategic approach to profoundly understanding each customer. By consolidating data from different sources into a single, deduplicated profile, businesses can gain an incredibly nuanced understanding of individual consumer behaviors, preferences, and patterns. This granular level of detail enables hyper-personalized marketing initiatives, targeted product recommendations, and even tailor-made customer service interactions. The ultimate goal is to foster individualized and thoughtful engagement rather than generic and one-size-fits-all.

By mastering identity resolution, businesses can go beyond superficial personalization tactics like using a customer's first name in an email. The stakes are higher now; consumers expect brands to understand their needs even before they articulate them. It is about the Customer Experience and their journey across your brand. Inaccurate identity resolution can lead to missed opportunities, such as showing irrelevant ads or recommending the wrong products, diminishing the customer experience, and potentially losing a sale. On the other hand, accurate identity resolution can facilitate real-time decision-making and dynamic content customization, setting the stage for meeting and exceeding customer expectations. Therefore, in the grand scheme of delivering a world-class customer experience, identity resolution isn't just beneficial—it's critical.

Unified Marketing Efforts

Without identity resolution, your marketing strategies can feel like shooting arrows in the dark. Each marketing channel - email, social media, or paid search; functions in isolation, lacking the context and cohesion from understanding the customer's journey across multiple touchpoints. You might be blasting emails to a segment already engaged through social media or missing out on retargeting opportunities because the data from your online store isn't integrated with your advertising platforms. The inefficiency of such a scattered approach can lead to wasted resources and, ultimately, a diluted brand message.

Identity resolution enables a marketer to recognize a customer from one touchpoint to another, forming the basis for a coherent omnichannel or multi-channel strategy. With a unified customer profile that aggregates data from various sources, you can ensure that your marketing messages are consistent but also relevant and timely. For example, if a customer bought a pair of running shoes on your e-commerce site, your email marketing can shift from product promotion to tips on maintaining the new purchase. Meanwhile, social media ads could focus on complementary products like fitness trackers or athletic apparel. In this way, each channel builds upon the other, creating a more compelling and engaging customer experience. This approach is true omnichannel personalization.

Moreover, unified marketing efforts powered by accurate identity resolution can provide invaluable insights into the customer lifecycle. By tracking a customer's interactions across channels, marketers can identify critical touchpoints that lead to conversion or, conversely, points where customers typically drop off. These insights can guide strategic decisions, such as where to allocate budget or which channels need optimization, thus driving ROI more effectively. Therefore, identity resolution isn't just a tool for cohesion; it's an essential component for the intelligence and effectiveness of your overall marketing strategy.

Regulatory Compliance

The landscape of digital marketing is a minefield of regulations, including the General Data Protection Regulation (GDPR) in Europe, the California Consumer Privacy Act (CCPA) in the United States, and many other similar laws across the globe. These regulations have specific requirements for collecting, storing, and using consumer data. A robust identity resolution strategy can help businesses navigate this complex regulatory environment by ensuring that all customer data is accurately tagged, mapped, and stored in compliance with regional laws. Furthermore, a solid identity resolution process can aid in record-keeping, making it easier for companies to demonstrate compliance during an audit or inquiry.

Aside from assisting with general compliance, identity resolution tools often have features that specifically address these regulatory requirements. For example, they may include options for data anonymization or pseudonymization, which can help companies use valuable customer data for analytics without violating privacy rules. Some solutions also offer built-in consent management, allowing businesses to track which customers have agreed to what types of data usage, an essential feature in the age of GDPR and similar regulations. In this way, an identity resolution strategy enhances marketing efforts and serves as a cornerstone for responsible and compliant data management.

Challenges in Identity Resolution

  • Data Fragmentation: Modern customers interact with brands across various platforms and devices, often leaving scattered data fragments. Collating this data into a single identity is a massive challenge.
  • Real-Time Expectations: Customers today expect real-time, seamless interactions across all touchpoints, which poses a unique challenge to identity resolution strategies. While matching and merging various identifiers may not necessarily need to be conducted in real-time, the finalized, holistic customer profile must be available in real-time for any omnichannel content delivery solutions that rely on it. Once a profile is created or updated, it needs to be immediately accessible for personalization and targeting across all channels, whether that's a mobile app, an online store, or a physical retail location. This real-time availability requirement adds a layer of complexity to identity resolution, demanding both speed and accuracy in data processing and integration. Many vendors accommodate this challenge, but many cannot and say they can, so be careful in your analysis of what they do.
  • Quality of Data: Ensuring high-quality data is a significant hurdle in identity resolution. Raw data often arrives unstructured and riddled with errors like typos or duplications. These inaccuracies can compromise the effectiveness of later matching and merging steps. Therefore, the initial stages of identity resolution must focus on cleaning and standardizing data to prepare it for more advanced processes.

Core Components of Identity Resolution

The overall process can be summarized like this image.
  • Data Ingestion: The first stage involves collecting data from multiple sources, often in various formats and structures.
  • Data Cleaning and Transformation: The next step is to cleanse the data by eliminating errors and inconsistencies and transforming it into a standard format.
  • Data Standardization: Data standardization involves enforcing data consistency across the board, often by implementing machine learning algorithms and setting up rules-based frameworks. Some vendors will integrate services like Melissa for reverse append contact clean-up, or USPS to standardize address fields.
  • Indexes, Databases, and Identity Graphs: At this stage, data from different sources are matched and linked to create a unified customer profile. Probabilistic and deterministic methods often assist in this.
  • Final Deduplication and Identity Verification: Finally, any remaining duplicates are removed, and a single, verified identity is formed for each customer. Often called the GOLD Profile or GOLD Customer Record (GCR). Some vendors add another option to combine multiple profiles into a household. You will see terms like Grouping or Householding - this process helps reduce cost for companies with multi-year print catalog drops or reduce the amount of marketing messages a single household would consume.

Types of Identity Resolution Models

Summary of how each approach might work. The nodes can be different from vendor to vendor based on their process and customization of the approach. See the definitions below.
  • Medallion Approach: This model consists of Bronze, Silver, and Gold stages, each with tasks like data ingestion, light transformation, and data enrichment. MDM(master data management) started the foundation of this approach. It is a core approach for most data management and CDP vendors. Typically, it is a staged, non-real-time resolution approach that is very accurate. In most cases, it deploys a deterministic algorithm or a hybrid with probabilistic.
  • Real-Time Index Approach: This approach focuses on real-time data ingestion and indexing, allowing immediate query and matching. This approach has a trade-off in that it has a high comparison collapse with more profiles involved. It is nearly 100% deterministic. Accuracy, precision, and latency all degrade as more profiles need matching. See image courtesy of Note: Zingg provides a Probabilistic approach and is not real-time but integrates with Spark and Snowflake. A real-time vendor would benefit by building in a hybrid model and leveraging Zingg as a value add with probabilistic/fuzzy match algorithms.
Courtesy of - As you can tell, if a single attribute deterministic model had to parse through 1m rows, it's really 500b rows it needs to compare. Imagine 30m or 60m - a large Fortune 500 company could severely deteriorate accuracy.
  • Graph dB-Based Approach: This approach stands out for its unique handling of relationships between various data entities. Unlike linear database structures, a graph database visualizes these relationships as interconnected nodes and edges, capturing more nuanced interactions and affiliations. The advanced algorithms traverse the rich network to resolve identities. Many vendors often integrate a graph database within a Medallion-style system, adding an extra layer of identity resolution at the end of the matching process. In many cases, it is probabilistic, but if Medallion is incorporated, it will include deterministic and become a hybrid approach.
  • Vector dB-Based Approach: The approach uses high-dimensional vectors representing identifiable features like email or device ID. These vectors are stored in a specialized database designed for quick similarity searches. Using machine learning algorithms like k-NN(k-Nearest Neighbors, a type of instance-based learning algorithm used in machine learning and statistics. It's often used for classification and regression tasks), this method offers fast and accurate matching for incoming queries. It's a flexible and dynamic approach that fits well within a broader identity resolution strategy. Nearly, 100% probabilistic every time it's used, but it would be better used in a hybrid approach.
  • Blockchain-Based Approach: The approach utilizes blockchain's secure and unchangeable nature for identity resolution. It employs smart contracts for automated matching and offers globally unique identifiers called a DID (Decentralized ID). This method is beneficial for high-security and compliance-driven use cases. Always deterministic from my research, but it is the new kid on the block. haha, puns, right? I am encouraged by this approach as it could solve many regulatory and privacy issues and put the data back into the hands of the consumer.
  • Hybrid Approach: A combination of one or more of the above models designed for specific needs. It would deploy variations of deterministic and probabilistic within the 5 various approaches and in different configurations of math algorithm models. In other words, it's a customized approach by the ISV(Independent software vendor).

Best Practices for Effective Implementation

  • Audit your Current Capabilities: Knowing where you stand is essential for deciding where you want to go. Perform an audit of your existing identity resolution capabilities.
  • Choose the Right Approach: Select the best approach(s) based on your specific needs and abilities.
  • Continuous Monitoring and Updates: Identity resolution is not a "set it and forget it" tool. Constant monitoring and regular updates are crucial.
  • Test and Optimize: Regularly test your system for efficiency and make necessary adjustments for optimization.


Identity resolution is not just a need but a necessity in today's ever-complicated digital marketing world. Businesses that can master the art of identity resolution stand to gain a significant competitive edge through improved customer experience, better ROI, and compliance with regulatory norms.

By understanding the importance, challenges, and different types of identity resolution models, organizations can better prepare themselves to navigate the complex landscape of modern digital marketing. Choose your path wisely.

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