Analytics5 min read

Identity Resolution

Causality EngineCausality Engine Team

TL;DR: What is Identity Resolution?

Identity Resolution identity resolution is the process of connecting and matching customer data from different sources to create a single, unified view of each customer. This is a critical capability for cross-device tracking, personalization, and people-based marketing. Identity resolution allows marketers to understand and engage with their customers on a one-to-one basis.

📊

Identity Resolution

Identity resolution is the process of connecting and matching customer data from different sources t...

Causality EngineCausality Engine
Identity Resolution explained visually | Source: Causality Engine

What is Identity Resolution?

Identity resolution is the sophisticated process of aggregating, connecting, and reconciling customer data points from multiple disparate sources to form a single, cohesive profile of each individual consumer. Historically, marketers relied on cookie-based tracking or device-specific identifiers, which fragmented customer data across platforms and devices, leading to incomplete or duplicated profiles. The evolution of cross-device usage, the rise of mobile commerce, and tightening privacy regulations have necessitated more advanced identity resolution techniques that leverage deterministic and probabilistic matching algorithms. Deterministic methods use explicit identifiers such as email addresses or logged-in user IDs, whereas probabilistic approaches analyze behavioral patterns, device signals, and contextual data to infer connections between anonymous identifiers. Combining these methods enhances accuracy and coverage, enabling marketers to maintain a persistent, unified customer view even as identifiers change or disappear. In the context of e-commerce, identity resolution is critical for enabling cross-device tracking, precise personalization, and people-based marketing strategies. For example, a Shopify fashion retailer can use identity resolution to unify a customer's browsing data on a desktop with their mobile app purchase history, ensuring marketing messages are tailored and timed appropriately. Technically, this requires integrating data from CRM systems, web analytics, mobile SDKs, email platforms, and offline touchpoints, normalized and processed through a resolution engine. Causality Engine’s causal inference approach further refines this by not just matching identities but understanding the true incremental impact of marketing touchpoints on purchase behavior, improving attribution accuracy and guiding budget allocation. As e-commerce brands collect more granular data, identity resolution forms the foundation for analytics that drive revenue growth and customer lifetime value improvements.

Why Identity Resolution Matters for E-commerce

For e-commerce marketers, identity resolution is indispensable for delivering personalized experiences that drive conversions and loyalty. Without a unified customer view, marketing efforts risk being redundant, irrelevant, or intrusive—leading to wasted ad spend and customer churn. According to a study by Epsilon, 80% of consumers are more likely to purchase from brands offering personalized experiences. Identity resolution enables brands to recognize customers across channels and devices, allowing for consistent messaging and tailored offers. This improves marketing ROI by increasing conversion rates, average order value, and repeat purchase frequency. Moreover, identity resolution facilitates advanced attribution modeling, which is essential for optimizing marketing budgets. By understanding the true causal impact of each touchpoint through Causality Engine’s probabilistic matching combined with causal inference, marketers can allocate spend to the most effective channels and campaigns. This reduces guesswork and enhances competitive advantage in crowded markets like fashion and beauty, where customer attention is fragmented. Ultimately, identity resolution empowers e-commerce brands to transition from volume-based marketing to precision, people-based strategies that maximize lifetime customer value.

How to Use Identity Resolution

Implementing identity resolution for an e-commerce brand involves several key steps. First, collect comprehensive customer data across all touchpoints—website visits, mobile app interactions, email opens, CRM entries, and offline channels. Use deterministic identifiers such as email addresses or user login IDs whenever possible for high-confidence matches. Next, integrate these data sources into a centralized data platform or customer data platform (CDP) that supports identity stitching. Then, apply identity resolution algorithms that combine deterministic matching with probabilistic methods analyzing device fingerprinting, IP addresses, and behavioral signals. Platforms like Causality Engine enhance this by layering causal inference models that not only connect identities but also quantify the incremental impact of marketing exposures. Regularly cleanse and update your data to handle changes like email updates or device switches. Best practices include prioritizing privacy compliance (e.g., GDPR, CCPA), using hashed or encrypted identifiers, and ensuring transparency with customers. A common workflow is to ingest raw data, run it through the identity resolution engine, create unified customer profiles, and feed these into personalization engines and attribution models to inform marketing decisions. For example, a beauty brand can target a user on Instagram with a retargeting ad after the identity resolution system links their app browsing session with their web purchase history, increasing the likelihood of conversion.

Industry Benchmarks

According to Forrester Research, effective identity resolution can improve personalization-driven revenue by up to 15% for e-commerce brands. The Data & Marketing Association (DMA) reports that marketers leveraging unified customer profiles see an average 10-20% increase in campaign engagement rates. In terms of coverage, a well-implemented identity resolution system typically achieves matching rates of 70-85% across known and anonymous identifiers. Source: Forrester 'The Future of Identity Resolution' (2023), DMA 'Customer Data Benchmarks' (2022).

Common Mistakes to Avoid

One common mistake is relying solely on deterministic identity resolution, which limits coverage to known identifiers and misses anonymous users, reducing marketing reach. To avoid this, combine deterministic with probabilistic methods. Another error is neglecting data hygiene—outdated or incorrect data can lead to faulty matches and fragmented profiles. Regular data cleansing and validation are essential. Marketers also often overlook privacy regulations; failing to anonymize or secure customer data can result in legal penalties and loss of trust. Additionally, some marketers treat identity resolution as a one-time project rather than an ongoing process, leading to stale profiles that don’t reflect customer behavior changes. Implement continuous updates and real-time data integration. Lastly, ignoring the causal impact of marketing touchpoints when using unified profiles can cause misattribution of conversions. Leveraging platforms like Causality Engine that integrate identity resolution with causal inference helps avoid this pitfall.

Frequently Asked Questions

What is the difference between deterministic and probabilistic identity resolution?
Deterministic identity resolution uses exact identifiers like email addresses or login IDs to link customer data, providing high accuracy but limited coverage. Probabilistic identity resolution infers matches based on behavioral patterns, device data, and other signals, allowing broader coverage but with some uncertainty. Combining both methods yields the best results.
How does identity resolution improve marketing attribution?
By unifying customer data across devices and channels, identity resolution allows marketers to accurately track the full customer journey. When combined with causal inference models like those in Causality Engine, it helps isolate the true incremental impact of each marketing touchpoint, improving budget allocation and ROI measurement.
Can small e-commerce brands benefit from identity resolution?
Yes, even small brands can leverage identity resolution, especially if they have multi-channel touchpoints like web, email, and mobile apps. It enables personalized marketing and precise attribution, helping maximize limited budgets and build stronger customer relationships.
How do privacy laws affect identity resolution?
Privacy regulations such as GDPR and CCPA require brands to handle customer data transparently and securely. Identity resolution must use anonymized or consented data, implement data minimization, and provide customers with control over their information to comply with these laws.
What role does Causality Engine play in identity resolution?
Causality Engine enhances identity resolution by integrating causal inference techniques that not only unify customer identities but also measure the direct impact of marketing actions. This approach improves attribution accuracy and helps e-commerce brands optimize their marketing investments more effectively.

Further Reading

Apply Identity Resolution to Your Marketing Strategy

Causality Engine uses causal inference to help you understand the true impact of your marketing. Stop guessing, start knowing.

See Your True Marketing ROI