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Causal Inference

6 min readUpdated Sep 8, 2026

How LLMs Mishandle NULL Values in Marketing Data

LLMs struggle with missing marketing data. NULL values cause inaccurate attribution. Causality Engine uses causal inference for robust behavioral intelligence, sidestepping LLM limitations.

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How LLMs Mishandle NULL Values in Marketing Data: LLMs struggle with missing marketing data. NULL values cause inaccurate attribution. Causality Engine uses causal inference for robust behavioral intelligence, sidestepping LLM limitations.

Read the full article below for detailed insights and actionable strategies.

The attribution problem

One sale. Four channels. 400% credit claimed.

100
1 sale
Meta
100%
claimed
Google
100%
claimed
TikTok
100%
claimed
Klaviyo
100%
claimed

Reported revenue: 400 · Actual revenue: 100 · Gap: €300

Large language models (LLMs) aren't ready to handle the messy reality of marketing data, especially when NULL values are involved. Trying to use LLMs for attribution? Prepare for garbage in, garbage out. The problem isn't just a minor glitch; it's a fundamental flaw in how these models process information, leading to skewed insights and wasted ad spend. We'll show you why causal inference offers a superior approach.

Why LLMs Choke on Missing Data in Marketing

Marketing data is notoriously incomplete. Customer behavior is tracked across multiple platforms, and not every interaction is captured perfectly. This results in a high prevalence of NULL values, representing missing or unknown data points. LLMs, while impressive in their ability to generate text and perform some analytical tasks, struggle mightily with these gaps. They often make incorrect assumptions or simply ignore NULL values, leading to flawed conclusions about which marketing activities are actually driving sales.

LLMs: Impressive Text Generators, Terrible Data Analysts

LLMs excel at pattern recognition within the data they're trained on. However, when faced with missing information, they tend to extrapolate based on incomplete patterns, introducing bias. For example, if a customer's initial interaction with a brand is missing, an LLM might incorrectly attribute the final purchase to a later touchpoint, completely overlooking the crucial first step. This is not just theoretical. Benchmarks like Spider2-SQL (ICLR 2025 Oral) reveal the painful truth: GPT-4o solves only 10.1% of enterprise SQL tasks, and o1-preview only 17.1%. Marketing attribution databases have exactly this level of complexity. Expecting LLMs to magically handle missing data is, frankly, delusional.

The Illusion of Insights: Why LLM-Driven Attribution Fails

LLM-based attribution tools often mask their limitations with fancy visualizations and confident-sounding reports. But behind the curtain, they're making guesses based on incomplete data. These guesses are then presented as insights, leading marketers to make decisions based on faulty information. This can result in overspending on ineffective channels and underinvesting in strategies that truly drive incremental sales. The cost? A significant chunk of your marketing budget flushed down the drain.

What Problems Arise From LLM Misinterpretations of NULL Values?

Using LLMs without properly addressing the problem of NULL values creates a cascade of issues. It's not just about slightly inaccurate reports; it's about fundamentally misunderstanding customer behavior and misallocating resources.

Skewed Attribution Models

LLMs struggle to accurately weigh the impact of different touchpoints when data is missing. Imagine a scenario where a customer clicks on a Facebook ad, visits your website (but the session isn't tracked due to a cookie issue), and then makes a purchase after seeing a retargeting ad on Instagram. An LLM might incorrectly attribute the sale solely to the Instagram ad, ignoring the initial Facebook interaction and the crucial website visit. This leads to an overvaluation of Instagram and an undervaluation of Facebook, resulting in a misallocation of ad spend.

Inaccurate Customer Segmentation

Missing data can also distort customer segmentation. If key demographic information or behavioral data is missing for a group of customers, an LLM might misclassify them, leading to ineffective targeting. For example, if the age of a customer is NULL, the LLM may assume the age based on other demographic trends. This is a great way to alienate and annoy your target market.

Flawed Predictive Models

LLMs are often used to predict future customer behavior. However, if the historical data used to train these models contains a significant number of NULL values, the resulting predictions will be unreliable. Imagine trying to forecast sales based on past performance, but a large portion of your sales data is missing. The forecast will be wildly inaccurate, leading to poor inventory management and lost revenue.

How Does Causality Engine Handle Missing Data More Effectively?

See also: Causal Forests and Average Treatment Effects in Marketing Attribution

Causality Engine takes a fundamentally different approach to behavioral intelligence. Instead of relying on pattern recognition and correlation, we use causal inference to identify the true drivers of customer behavior. This approach is far more robust to missing data because it focuses on understanding the underlying causal relationships, rather than simply identifying correlations.

Causal Inference: The Solution to the Missing Data Problem

Causal inference allows us to determine the causal impact of different marketing activities, even when data is incomplete. By using techniques like do-calculus and instrumental variables, we can control for confounding factors and isolate the true effect of each touchpoint. This means that even if some data is missing, we can still accurately attribute sales to the right activities.

Building Robust Causality Chains

Causality Engine builds causality chains that model the entire customer journey, from initial awareness to final purchase. These chains capture the complex relationships between different touchpoints and allow us to understand how they interact to drive sales. By understanding these causal relationships, we can accurately attribute sales even when some data is missing.

Real-World Results: Causality Engine Delivers Accurate Insights

Our customers have seen significant improvements in their marketing performance by switching to Causality Engine. One beauty brand increased their ROAS from 3.9x to 5.2x, resulting in an additional 78,000 EUR per month in revenue.964 companies trust Causality Engine to drive their behavioral intelligence. These results demonstrate the power of causal inference to overcome the limitations of traditional attribution methods, especially when dealing with missing data.

Stop Letting NULL Values Ruin Your Marketing

LLMs are great for generating text, but they're terrible at handling missing data in marketing. If you're relying on LLM-based attribution, you're likely making decisions based on flawed insights. Causality Engine offers a better way. Our causal inference approach is robust to missing data and delivers accurate, actionable insights that can drive significant improvements in your marketing performance. It's time to ditch the broken attribution models and embrace the power of causality.

Ready to see how Causality Engine can transform your marketing? Request a demo and discover the power of causal inference.

Sources and Further Reading

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Key Terms in This Article

Attribution Model

An Attribution Model defines how credit for conversions is assigned to marketing touchpoints. It dictates how marketing channels receive credit for sales.

Causal Forests

Causal Forests are a machine learning method that estimates heterogeneous treatment effects, extending random forests for causal inference.

Causal Inference

Causal Inference determines the independent, actual effect of a phenomenon within a system, identifying true cause-and-effect relationships.

Customer journey

Customer journey is the path and sequence of interactions customers have with a website. Customers use multiple devices and channels, making a consistent experience crucial.

Instrumental Variable

Instrumental Variable is a causal analysis method that estimates a variable's true effect when controlled experiments are not possible, using a third variable that influences the outcome only through the explanatory variable.

Marketing Attribution

Marketing attribution assigns credit to marketing touchpoints that contribute to a conversion or sale. Causal inference enhances attribution models by identifying true cause-effect relationships.

Marketing Mix Modeling

Marketing Mix Modeling (MMM) is a statistical analysis that estimates the impact of marketing and advertising campaigns on sales. It quantifies each channel's contribution to sales.

Treatment Effect

Treatment Effect is the causal impact of an intervention on an outcome. In marketing, this means the change in a metric like conversion rate directly caused by a campaign or pricing adjustment.

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Frequently Asked Questions

Why are NULL values a problem for LLMs in marketing?

LLMs struggle with incomplete data, often making incorrect assumptions or ignoring NULL values entirely. This leads to skewed attribution models, inaccurate customer segmentation, and flawed predictive models, resulting in wasted ad spend.

How does Causality Engine handle missing data?

Causality Engine uses causal inference to identify the true drivers of customer behavior, even when data is incomplete. By building robust causality chains, we can accurately attribute sales to the right activities, overcoming the limitations of traditional methods.

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