KNOWLEDGE NOTES

Knowledge Notes

Explore curated knowledge, course notes and methods, with their existing content and sources preserved.

This index lists complete English editions. Additional Chinese notes and bilingual updates remain available in the Chinese index.

350knowledge notes
Product Design & UX / AI Products and Assisted Design

AI-Assisted UX · Discovery and Research Phase (Prompts and Workflows for Using AI to Define Business/Experience Goals, MVP Metrics, Problem Framing, User Research Reports, and Background Infographics)

This is the prompt and workflow handbook for the first phase (Discover & Research) of Will’s "AI-Assisted UX Workflow". It covers 7 tasks in the discovery and research phase that can be accelerated by AI: ① Distill scattered project background into a professional "Project Background (PB) statement" ② Derive business goals × experience goals × plain-language driving logic from the background ③ Locate experience problems on old interfaces and quantify their metric impact ④ Rewrite vague problems into actionable problem statements + problem overview diagrams ⑤ Use MVP hypothesis/metric scripts for interview verbal delivery ⑥ Generate a fully structured product concept user research report (including simulated data + risk and objection signals) ⑦ Convert content into "chart prompts" for professional infographics. Each section provides reusable prompt skeletons + Why explanations + counterexamples + sample outputs. It also includes the underlying mental models (business outcome = traffic × conversion × cost, experience only acts on the behavioral layer, MVP dual hypotheses, four-dimensional demand scoring). It complements google-ux-research: that piece covers UX research methods themselves (how to conduct interviews/draw empathy maps/run usability tests), while this piece explains how to use AI to quickly turn these research outputs into deliverables suitable for reporting or inclusion in a portfolio. It is oriented toward non-technical PMs, with jargon explained in parentheses.

AI-Assisted ResearchUser researchProduct GoalsEnglish edition
Product Design & UX / Other Product, Design and Learning Materials

Curated Highlights of Medium UX Articles (Multi-Topic: GenAI UX Patterns / Research & Experiment Methods / Mobile Trends / Inclusivity / Information Architecture / Company Cases)

A curated compilation of highlights from 102 Medium UX articles (59 topics) saved by Will, compressed across 7 major clusters into one note that can replace an entire bookmarks folder. ① GenAI/AI UX Patterns — 21 GenAI UX Patterns (augmentation vs automation / three tiers of automation / CoT display / expressing model confidence and limitations / guardrails), seven AI UI layouts (floating window / inline / infinite canvas / centered chat / left panel / right panel / grid), predictive UX (context management controls), five-step framework for designing AI products. ② Research & Experiment Methods — five-step A/B testing method (define success → identify bottlenecks → build hypotheses → prioritize → test, including empirical evidence from the Obama campaign's $57 million and Haiti disaster relief's $1.02 million), macro vs micro vs vanity metrics. ③ Mobile & Trends — nine 2026 mobile trends (predictive / Zero-UI / Agentic / spatial 3D / glassmorphism / microinteractions / adaptive / ethics / passwordless). ④ Inclusivity/Accessibility — 11 tactics (4.5:1 contrast ratio / multi-channel coding / external form labels / alt text / heading hierarchy / touch targets ≥7–10 mm² / keyboard accessibility), including empirical revenue evidence from Tesco/Virgin. ⑤ Information Architecture/Flows/Complexity — collaboration framework (centralized → decentralized shared Commons), how complexity accumulates (feature bloat / process stacking / technical debt + Pareto cuts + complexity budget), value proposition canvas, globalization ≠ translation (Chevrolet Nova / Domino's vs Kellogg's). ⑥ Company Cases — breakdown index for Airbnb/Calm/Canva/Duolingo/Spotify/Uber/Slack/Gmail and more. ⑦ Career/Soft Skills — three types of designers in 2026 (block-shaped generalists / ultra-deep specialists / standout new graduates), real UX competence in the AI era (restraint and judgment > drawing UI), six psychology principles for landing page conversion. For AI product PMs: Why / when to use / counterexamples come first. Highly intertextual with [[shape-of-ai-patterns]] (AI UX Pattern Library), [[ai-ux-interactions]] (Seven AI Interaction Paradigms), [[laws-of-ux]] (Laws of UX), [[nngroup-ux-principles]] (UX Golden Quotes), [[nngroup-information-architecture]], [[nngroup-persuasive-design]], and [[ux-metrics-roi]]; this compilation only adds the checklists, numbers, and cases they do not cover, and does not rewrite them.

AI UXUser researchAccessibilityEnglish edition
Product Design & UX / Google UX Courses

Google UX Certificate / UX Research and Empathy - Define

The complete research craft collection from Google UX Certificate Course 2 (Empathize/Define) + Course 4 (Conduct UX Research). Covers 5-step interview SOP + 5 traits of research objectives/participants/questions + empathy map (Says/Thinks/Does/Feels) + persona vs user profile + problem statement (formula + 5W1H) + hypothesis statement (if-then / we believe) + 4-step value proposition + human factors engineering (WWI/WWII history) + design psychology (color/Von Restorff/serial position/Hick's Law/mental model/feedback loop + ethics) + 7 elements of a research plan + usability study (pros and cons of moderated vs unmoderated + best practices before/during/after + note-taking methods) + moderator/participant bias + affinity diagram analysis + patterns → themes + 5 criteria for strong insights + 7 presentation tips. Targeted at PMs, cross-referenced with Yitang research/user interview methodology.

User researchInterviewUsability testingEnglish edition
Product Design & UX / Other Product, Design and Learning Materials

Icon Design Research: Digital Icons That Work (Icon Association Survey: 10,700 Responses + Design Principles + High-Risk Icon Checklist)

Highlights from a large-scale Icon Association Ranking survey: 107 U.S. participants × 100 icons = 10,700 open-ended responses, covering the primary associated meaning, recognition rate percentage, and 95% confidence interval for each icon when presented alone, without text or context. Core finding: There is no such thing as a "Universal Icon" — no icon is consistently understood across all systems. Recognition rates fall into three tiers: 65–100% (high consensus, e.g., trash can = delete 98%, shopping cart = checkout 98%, pencil = edit 96%, envelope = mail 95%, circled question mark = help 91%, house = home 91%) / 50–64.9% (medium consensus, e.g., hamburger menu = menu only 59%, funnel = filter 53%) / 0–49.9% (weak consensus, e.g., share arrows, sparkles for AI, lifebuoy for help, AR cube). Coverage: survey methodology (two-stage testing: out-of-context vs. in-context) / three icon types (resemblance/metaphorical/arbitrary) and cognitive distance / 10 design principles (follow convention, single concept, consistent meaning, appropriate metaphor, etc.) + real-world counterexamples (Reddit wrench, TripIt star upgrade, Rippling heart for insurance, Lyft golf cart for shopping cart, DoorDash lifebuoy for help) / 8 factors affecting comprehension (consistency, interaction frequency, prior experience, proximity, text labels, orientation, placement, cultural background) / when text labels are mandatory / why emerging icons all fail (AI sparkles 0% recognition, heartbeat for data, lightning for charging 37%). Audience: product managers; jargon explained in plain language; every section includes Why + numbers + counterexamples.

Icon designUser researchUsabilityEnglish edition
Product Design & UX / NNGroup User Experience

NNGroup Usability Testing and the 10 Usability Heuristics (Complete table of 10 heuristics · Application to complex applications · User delight hierarchy · Testing methods: 5-user rule/recruitment/remote testing/task scenarios/stepped tasks/attitudinal vs behavioral/4-step analysis/small-sample error/competitive evaluation)

A curated knowledge base of 22 essential pieces from Nielsen Norman Group on usability testing and usability heuristics, organized around two core axes: ① The 10 usability heuristics proposed by Jakob Nielsen in 1994 (used for design self-checks and heuristic evaluations): Visibility of System Status / Match Between System and the Real World / User Control and Freedom / Consistency and Standards (including internal + external consistency · Jakob's Law) / Error Prevention (prioritize high-risk scenarios) / Recognition Rather than Recall / Flexibility and Efficiency of Use (accelerators) / Aesthetic and Minimalist Design (signal-to-noise ratio) / Help Users Recognize, Diagnose, and Recover from Errors / Help and Documentation — each entry includes core principles, do/don't guidance, and counterexamples, plus application notes for complex enterprise applications (ArcMap/Power BI/Salesforce/Revit/Solidworks/Jitterbit); User Delight is built on a four-level pyramid (Aarron Walter) of functionality-reliability-usability-delight, covering surface delight vs deep delight plus the negativity bias effect. ② Usability testing methods: the golden rule that 5 users uncover 85% of problems and its exceptions (quantitative studies ≥20 users · card sorting ≥15 users · eye tracking 39 users · agile 2–3 users · empirical evidence from 83 studies), participant recruitment ($171 per participant · agency vs internal recruitment · incentives · 11% no-show rate · survey of 201 people), 7 steps for moderated remote testing, three techniques for task scenarios (realistic/actionable/no leading hints), Stepped Tasks research for discoverability and findability, Attitudinal vs Behavioral research, 4-step qualitative data analysis method (collect/examine/understand/validate), large measurement error in small samples (true value + measurement error · confidence intervals · statistical significance · do not report raw numbers alone), competitive usability evaluation (select 2–4 competitors · expert review vs user testing). Intended audience: product managers; terms are explained in industry language, with decision-oriented guidance.

Usability testingDesign heuristicsUser researchEnglish edition
Product Design & UX / Other Product, Design and Learning Materials

UX Metrics and ROI (HEART/SUS/NPS… Metric System + Methods to Convert UX Value into Monetary Terms + Reporting Talking Points)

Highlights from Will's Design Notes *UX Metrics and ROI* (based on the NN/g research report of the same name + a 5-edition case library). It focuses on the three things PMs need most: ① Metric system checklist — what each UX metric (task completion rate / time on task / success rate / conversion rate / retention / CLV / bounce rate…) looks like, how to calculate it, when to use it, and what its limitations are; how to interpret standardized questionnaires SUS (System Usability Scale, full score 100), NPS (Net Promoter Score = %Promoters − %Detractors), and CSAT; the five dimensions of Google's HEART framework (Happiness / Engagement / Adoption / Retention / Task success) as a scaffold for metric selection; what questions each of the four major data sources (surveys / quantitative usability testing / analytics tools / customer service and marketing data) answers. ② UX→ROI conversion methodology — improvement score formula (positive metric = post-change ÷ pre-change − 1; negative metric = pre-change ÷ post-change − 1), three-step method (select KPI → convert UX metrics to KPI by unit → report responsibly), how to convert to monetary value for four types of business models (e-commerce by sales volume / content sites by PV-based advertising / intranets by person-day wages / sites with clear target actions by conversion × average order value), retaining all exact figures including health insurance site saving 1.5 million yuan/year, HR tool saving $6,112 per month / 60% of work hours, financial subscription trial increasing monthly revenue by $20,000 from 76 to 187, and intranet ROI reaching 8/20/50 times the cost for companies with 1,000/10,000/100,000 employees; also presents Athenahealth's chained correlation model of "usability → satisfaction → willingness to recommend → retention and paid referrals", teaching PMs to connect soft metrics to revenue KPIs using statistical correlation. ③ Expectation management and reporting talking points — the "narrowing improvement" pattern that UX redesigns deliver an average 75% lift (95% confidence interval 8%~104%), and that this figure shrank from 247% to 75% from 2006 to 2020 (p=0.017), broken down by metric category (effectiveness 131% / efficiency 104% / adoption & retention 93% / engagement 87% / satisfaction 19%); 5 iron rules for reporting to bosses (estimates are not financial reports / compare against R&D costs / tell stories instead of piling tables / be transparent about assumptions / extend the timeline to 2–5 years) plus counterexamples. It complements *nngroup-analytics-metrics*: that piece covers NN/g's "analytics and measurement perspective" (vanity metrics / confidence intervals / statistical significance / sampling / triangulation / four-step ROI principle), while this piece is a "complete metric system checklist + improvement score math + multi-business-model ROI conversion recipes + empirical baseline magnitude data + reporting talking points"; overlapping content (four-step ROI / HEART / confidence intervals) is only cross-referenced and not rewritten. Target audience: product managers.

UX MetricsUser researchROIEnglish edition