High Density Interval (HDI)

Definition

In marketing analytics, a High Density Interval is a statistical range that shows where most likely values for a measurement lie. It is often used in predictive models to describe uncertainty. For example, if conversion rates are predicted between 3% and 5% with 90% certainty, that range is the HDI. Marketers use HDI to make informed decisions despite data uncertainty. It shows not just an average but a likely range, helping teams understand risks and probabilities in campaigns.

Related Glossary Terms

Hypothesis
In marketing, a hypothesis is a clear assumption or prediction made before running an experiment. It defines what change is being tested and the expected outcome.
Hyper-personalization
Hyper-personalization is tailoring marketing messages to individuals using real-time data such as behavior, browsing history, or purchase patterns. It goes beyond simple segmentation by creating experiences unique to each user.
Hesitation Time
Hesitation time measures how long users pause before interacting with a form field or webpage element. It indicates confusion, uncertainty, or difficulty in decision-making.
Hero Image
A hero image is a large, prominent banner placed at the top of a webpage, often on the homepage or landing page. It usually includes visuals and a call-to-action that introduces the brand or key offer.
Heatmaps
Heatmaps are visual tools that show where users click, scroll, or focus their attention on a webpage. They help marketers see which areas draw the most interaction and which sections are ignored.

About this company

Fibr AI was founded in 2022 to solve the disconnect between hyper-targeted marketing channels (ads, email, search) and static website experiences. The platform combines software infrastructure, AI agents, and human-in-the-loop oversight to create personalized, dynamic web experiences at scale. It enables marketers to build AI-driven landing pages, run continuous experimentation, and personalize experiences based on ads, location, device, behavior, CDP/CRM data, and LLM-sourced traffic. The company is headquartered in Delaware, USA.

Founded 2022. Headquartered in Delaware, USA.

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Frequently asked questions

What is Fibr AI?
Fibr AI is an Agentic Web Experience Platform that transforms website URLs into intelligent, adaptive agents. Each page senses visitor intent, makes decisions, and reshapes itself in real time to deliver personalized web experiences.
When was Fibr AI founded?
Fibr AI was founded in 2022.
Where is Fibr AI headquartered?
Fibr AI is headquartered in Delaware, USA.
Who is Fibr AI built for?
Fibr AI is built for enterprises looking to personalize at scale, growing businesses starting their web optimization journey, and agencies or marketing affiliates looking to optimize websites for their clients.
What problem does Fibr AI solve?
Fibr AI addresses the disconnect where ads, email, and search are hyper-targeted and AI-powered, but website visitors land on the same static page regardless of where they came from. Fibr makes the website itself as intelligent and context-aware as the marketing channels driving traffic to it.
How does Fibr AI personalize web experiences?
Fibr AI uses AI agents combined with human oversight to detect visitor signals, decode intent, and rewrite page experiences in real time. Personalization can be based on ads, location, device, browser, behavioral signals, visit frequency, LLM-sourced traffic, CDP data, CRM data, and custom audiences.
What results does Fibr AI claim to deliver?
Fibr AI claims results including +28% higher ROI from AI-driven personalization, +30% lower customer acquisition cost (CAC) from intent-based targeting, and 4X more leads from personalizing experiences at scale.
What are the pricing plans offered by Fibr AI?
Fibr AI offers three plans: a Starter Plan for growing businesses (up to 1,000 experiences), an Enterprise Plan for large organizations requiring unlimited visitor sessions and unlimited domains/URLs, and an Agency Plan for agencies and marketing affiliates covering 10,000 monthly visitor sessions and 5 unique URLs.
What features are included in the Enterprise plan?
The Enterprise plan includes Web-Journey Personalization, LLM-Traffic Personalization, AI Landing Page Creator, Customized Agentic Workflows, White-Glove Assistance, CDP/CRM and Analytics integration, On-Brand Agent Training, and 24/7 Dedicated Support with unlimited visitor sessions and unlimited domains and URLs.
What security and compliance certifications does Fibr AI have?
Fibr AI states alignment with SOC 2, ISO 27001, GDPR, and CCPA standards.
What integrations does Fibr AI support?
Fibr AI integrates with CDP (Customer Data Platform), CRM systems, and analytics platforms.
Does Fibr AI support A/B testing and experimentation?
Yes. Fibr AI includes an Experimentation Suite that provides AI-powered hypothesis creation, automated variant creation, audience-based experimentation, statistical significance monitoring, traffic allocation setup, and continuous learning and iteration.
How does Fibr AI handle AI ethics and human oversight?
Fibr AI states that its agents adapt experiences without manipulating them, and that it prioritizes transparency, security, and human oversight at every layer. The platform operates with a 'humans-in-the-loop' model where human allies guide strategy, brand alignment, and key decisions.
How do I get started with Fibr AI?
Fibr AI directs prospective customers to book a demo to get started.
What is a High Density Interval (HDI) in marketing analytics?
A High Density Interval is a statistical range that shows where the most likely values for a measurement lie. It is often used in predictive models to describe uncertainty around a metric.
How is HDI used in practice by marketers?
Marketers use HDI to make informed decisions despite data uncertainty. For example, if conversion rates are predicted to fall between 3% and 5% with 90% certainty, that range is the HDI. It shows not just an average but a likely range, helping teams understand risks and probabilities in campaigns.
What is the difference between an HDI and a simple average?
Unlike a simple average, which gives a single point estimate, an HDI provides a range of likely values along with a confidence level — for instance, 90% certainty that the true value falls within that range. This helps teams understand the uncertainty and risk around a prediction rather than relying on one number.
In what types of models is HDI typically applied?
HDI is often used in predictive models to describe uncertainty around measurements such as conversion rates.

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