Intellectica SDSI Index™ — Methodology v1.0
Intellectica Research

Skills Demand-Supply Intensity Index (SDSI)

Measuring how tight a skill-specific labor market is relative to the overall economy.

Version
v1.0
Published
May 2026
Cadence
Monthly
Source
LinkedIn Talent Insights
Coverage
12 skill baskets · 121 skills

1. Overview

The Intellectica Skills Demand-Supply Intensity Index™ (SDSI Index) measures how tight the labor market is for a specific skill category in a country, both in absolute terms and relative to the overall market. It provides business leaders and HR decision-makers with a clear, comparable metric that quantifies talent scarcity across skill domains.

The index answers a single question: how does demand-supply tension for a specific skill category compare to the overall labor market? It produces a percentage-based score anchored at 100%, where 100% represents market-average tension. Values above 100% indicate a tighter-than-average skill market; values below 100% indicate a looser-than-average one.

The SDSI Index is designed as a cross-sectional framework: 12 skill baskets are tracked simultaneously within a country, covering technology, business functions, design, and professional services. This allows direct comparison of relative talent tension across domains from the very first release. The time series builds forward with each monthly publication.

1.1 Why this index exists

Existing labor market indicators tend to be either too broad (economy-wide unemployment rates) or too narrow (individual company hiring metrics). Business leaders making talent strategy decisions need a middle layer: skill-specific demand-supply signals that can be compared across domains and tracked over time. The SDSI Index fills this gap by translating LinkedIn Talent Insights data into a standardized, interpretable metric.

1.2 Audience

The primary audience is business leaders and HR decision-makers — professionals asking questions such as: Should we be concerned about finding AI talent in Greece? Which skill domains are experiencing the greatest hiring pressure? Is the talent scarcity we feel in our sector real, or is the entire market tight? The SDSI Index provides the quantitative basis for these conversations.

2. Data Sources

The SDSI Index uses a single data source to maintain methodological simplicity and eliminate cross-source comparability issues.

2.1 LinkedIn Talent Insights

LinkedIn Talent Insights is a proprietary analytics platform providing real-time data on the professional workforce. It is the sole data source for the SDSI Index.

  • Update frequency. Near real-time — professional profiles and job postings update continuously.
  • Access type. Paid subscription.
  • Historical depth. None. LinkedIn Talent Insights provides current-state snapshots only; there is no way to query historical values for past dates. The index begins live from launch.
  • Known limitations. LinkedIn over-represents white-collar, urban, tech-adjacent professionals. Coverage is strong for knowledge-work domains but structurally incomplete for manual trades, the informal economy, and non-digital sectors.

3. Components & Dimensions

The SDSI Index is a measurement framework applied across 12 skill baskets spanning technology, business functions, design, and professional services. Each basket represents a distinct professional domain. The framework produces a SDSI score for each basket, enabling cross-sectional comparison.

Two core metrics are calculated per basket: the Tightness Ratio (absolute demand-supply balance) and the Skills Demand-Supply Intensity score (relative to the overall market).

3.1 Skill basket construction principles

Each skill basket is a curated list of LinkedIn skill tags representing a professional domain. The following principles govern basket construction:

  • Domain essentiality. A skill belongs in a basket if it is essential to working in that domain, even if it is also used in other fields. The test: is this skill a core part of the practitioner's toolkit in this domain? For example, Python is not exclusively an AI skill, but it is essential to virtually all AI work. A skill that is merely incidentally associated with the domain does not qualify.
  • Taxonomy-level consistency. Skills should be selected at mid-level specificity — not umbrella terms (e.g., not "Artificial Intelligence" as a catch-all) and not niche techniques (e.g., not "Hyperparameter Tuning"). Preferred level: Machine Learning, Deep Learning, Computer Vision, NLP, Generative AI.
  • Dominance monitoring. If a single skill accounts for more than 40–50% of the basket's total professional count when queried independently, it is flagged as a dominant skill. Dominant skills are not automatically excluded if they pass the domain-essentiality test, but they are monitored at each release. The SDSI is tracked in parallel with and without the dominant skill; if the two values diverge significantly over time, the skill's inclusion is reconsidered.
  • Basket size target: 10 ± 3 skills (7–13 per basket). Fewer than 7 creates fragility; more than 13 dilutes toward the general market. Not every domain will hit the same number. All baskets are documented with their exact skill lists.
  • Longevity over trendiness. Prefer skills that will remain meaningful for 5+ years. Emerging skills may be included but are flagged as candidates for the 6-month review cycle. Brand-name skills (e.g., AWS, Salesforce, Figma) are included only when they function as de facto industry categories with 10+ years of stability.
  • Selection-time checklist. Each skill is validated at selection time using five questions: Does it pass domain essentiality? Is it at mid-level specificity? Does it show a non-trivial professional count in the target country? Does it trigger dominance monitoring? Is it likely relevant in 5+ years? All five must be assessed for inclusion.

3.2 Basket overview

The SDSI Index tracks 12 skill baskets covering 121 skills across the knowledge-work economy:

BasketSkillsDomain Layers
AI & Data Science13Core AI/ML · Domain · Generative AI · ML Frameworks · ML Infrastructure · Essential Tooling · Essential Analytical
Cybersecurity10Core Defense · Offensive Security · Operations · Cloud Layer · Access Control · Threat Analysis · Security Tooling
Cloud Computing & DevOps10Core · Cloud Platforms · Methodology · Container Orchestration · Containerization · IaC · Deployment Pipelines · Automation
Software Engineering11Core · Essential Language · Frontend Framework · Backend Runtime · Design · Integration · Version Control · Essential Tooling
Digital Marketing11Core · Search · Social · Content · Analytics · Automation · Channels · Paid Media · Strategy
Finance & Accounting10Core · Analysis · Reporting · Assurance · Planning · Risk · Strategy · Operations · Regulatory
Human Resources & Talent Management10Core · Development · People Operations · Total Rewards · Strategy · Culture · Essential Tooling
Sales & Business Development10Core · Client Relations · Essential Tooling · Pipeline · Sales Model · Deal Skills · Strategy · Operations
Project Management9Core · Methodology · Portfolio · Communication · Planning · Transformation · Operations · Execution
Supply Chain & Logistics10Core · Sourcing · Warehouse · Planning · Storage · Analytics · Supplier Relations · Distribution · Purchasing
UX/UI & Product Design9Core · Research · Design · Prototyping · Testing · Structure · Essential Tooling
Legal & Compliance9Core · Specialization · Compliance · Privacy Regulation · Transactions · Practice · Operations

3.3 AI & Data Science (13 skills)

Skill TagDomain Layer
Machine LearningCore AI/ML
Deep LearningCore AI/ML
Neural NetworksCore AI/ML
Natural Language Processing (NLP)Domain — Language
Computer VisionDomain — Vision
Generative AIGenerative AI
Large Language Models (LLM)Generative AI
Retrieval-Augmented Generation (RAG)Generative AI — flagged for review
TensorFlowML Frameworks
PyTorchML Frameworks
MLOpsML Infrastructure
Python (Programming Language)Essential Tooling — dominant skill
Data ScienceEssential Analytical
Calibration notes

Python (Programming Language) accounts for approximately 78% of the basket population when queried independently. Retained under the domain-essentiality principle; monitored with-and-without at each release. RAG flagged for 6-month longevity review. Excluded: Artificial Intelligence (AI) umbrella tag, brand-specific skills (ChatGPT, GPT-4, DALL-E, LangChain), and insufficiently specific skills (Image Processing, OpenCV, Prompt Engineering).

3.4 Cybersecurity (10 skills)

Skill TagDomain Layer
Network SecurityCore Defense
Information SecurityCore Defense
CybersecurityCore Defense
Penetration TestingOffensive Security
Vulnerability AssessmentOffensive Security
Incident ResponseOperations
Cloud SecurityCloud Layer
Identity & Access Management (IAM)Access Control
Threat IntelligenceThreat Analysis
SIEMSecurity Tooling
Calibration notes

Minimal cross-basket overlap expected. Cloud Security may capture some professionals also in the Cloud Computing & DevOps basket.

3.5 Cloud Computing & DevOps (10 skills)

Skill TagDomain Layer
Cloud ComputingCore
Amazon Web Services (AWS)Cloud Platforms
Microsoft AzureCloud Platforms
Google Cloud Platform (GCP)Cloud Platforms
DevOpsMethodology
KubernetesContainer Orchestration
DockerContainerization
TerraformInfrastructure as Code
CI/CDDeployment Pipelines
Infrastructure as CodeAutomation
Calibration notes

AWS, Azure, and GCP are brand names but function as stable skill categories on LinkedIn (10+ years established). They collectively define the cloud market and pass the longevity test.

3.6 Software Engineering (11 skills)

Skill TagDomain Layer
Software DevelopmentCore
JavaScriptEssential Language
JavaEssential Language
TypeScriptEssential Language
React.jsFrontend Framework
Node.jsBackend Runtime
Web DevelopmentCore
Software ArchitectureDesign
RESTful APIsIntegration
GitVersion Control
SQLEssential Tooling
Calibration notes

SQL also appears in data contexts but is essential to virtually all software engineering work (domain-essentiality principle). JavaScript likely triggers dominance monitoring given its prevalence across the web development population.

3.7 Digital Marketing (11 skills)

Skill TagDomain Layer
Digital MarketingCore
Search Engine Optimization (SEO)Search
Search Engine Marketing (SEM)Search
Social Media MarketingSocial
Content MarketingContent
Content StrategyContent
Google AnalyticsAnalytics
Marketing AutomationAutomation
Email MarketingChannels
Pay-Per-Click (PPC)Paid Media
Marketing StrategyStrategy
Calibration notes

Google Analytics is a brand name but has been the industry standard for 15+ years and functions as a skill category on LinkedIn. Digital Marketing as a tag may trigger dominance monitoring.

3.8 Finance & Accounting (10 skills)

Skill TagDomain Layer
Financial AnalysisCore
AccountingCore
Financial ModelingAnalysis
Financial ReportingReporting
AuditingAssurance
BudgetingPlanning
Risk ManagementRisk
Corporate FinanceStrategy
Management AccountingOperations
TaxationRegulatory
Calibration notes

Risk Management also appears in other professional contexts (e.g., project management, compliance). Cross-basket overlap is expected and documented.

3.9 Human Resources & Talent Management (10 skills)

Skill TagDomain Layer
Human Resource ManagementCore
Learning & DevelopmentDevelopment
Employee RelationsPeople Operations
Organizational DevelopmentDevelopment
Performance ManagementDevelopment
Compensation & BenefitsTotal Rewards
Talent ManagementStrategy
Workforce PlanningStrategy
Employee EngagementCulture
HRISEssential Tooling
Calibration notes

Recruiting and Talent Acquisition were excluded — they function as demand-side umbrella tags in HR job postings, inflating job-post counts across the entire HR domain. Empirical testing confirmed this: their inclusion produced a severely distorted SDSI driven almost entirely by recruiter demand rather than HR market tension. The umbrella tag Human Resources (HR) was also excluded on the same grounds.

3.10 Sales & Business Development (10 skills)

Skill TagDomain Layer
Sales ManagementCore
Business DevelopmentCore
Account ManagementClient Relations
CRMEssential Tooling
Salesforce.comEssential Tooling
Lead GenerationPipeline
B2B SalesSales Model
NegotiationDeal Skills
Sales StrategyStrategy
Pipeline ManagementOperations
Calibration notes

Salesforce.com is a brand name but has been the dominant CRM platform for 20+ years, functioning as a skill category. Negotiation may overlap with the Legal & Compliance basket.

3.11 Project Management (9 skills)

Skill TagDomain Layer
Project ManagementCore
Agile MethodologiesMethodology
ScrumMethodology
Program ManagementPortfolio
Stakeholder ManagementCommunication
Project PlanningPlanning
Change ManagementTransformation
Business Process ImprovementOperations
Cross-functional Team LeadershipExecution
Calibration notes

Project Management as a tag is very widely listed and likely triggers dominance monitoring. Agile Methodologies and Scrum may overlap with Software Engineering professionals.

3.12 Supply Chain & Logistics (10 skills)

Skill TagDomain Layer
Supply Chain ManagementCore
Logistics ManagementCore
ProcurementSourcing
Inventory ManagementWarehouse
Demand PlanningPlanning
Warehouse ManagementStorage
Supply Chain OptimizationAnalytics
Vendor ManagementSupplier Relations
Transportation ManagementDistribution
SourcingPurchasing
Calibration notes

Especially relevant for Greece given its shipping and trade economy. LinkedIn coverage is reasonable for mid-to-senior supply-chain professionals but may underrepresent operational warehouse staff.

3.13 UX/UI & Product Design (9 skills)

Skill TagDomain Layer
User Experience (UX)Core
User Interface DesignCore
UX ResearchResearch
Product DesignDesign
Interaction DesignDesign
WireframingPrototyping
Usability TestingTesting
Information ArchitectureStructure
FigmaEssential Tooling — flagged for review
Calibration notes

Figma is a brand but has become the de facto industry tool. Flagged for 6-month review given potential displacement risk. At 9 skills, this is the smallest basket in the framework.

3.14 Legal & Compliance (9 skills)

Skill TagDomain Layer
Legal ResearchCore
Corporate LawSpecialization
Contract LawSpecialization
Regulatory ComplianceCompliance
GDPRPrivacy Regulation
Due DiligenceTransactions
Legal WritingPractice
Intellectual PropertySpecialization
Contract ManagementOperations
Calibration notes

GDPR is regulation-specific but is the defining EU privacy framework with 10+ year expected stability. This basket carries the highest thin-signal risk in smaller markets; per the methodology, any basket with fewer than 50 job posts in a country is reported with an explicit low-confidence flag.

4. Calculation Formula

4.1 Step 1 — Tightness Ratio (TR)

The Tightness Ratio measures the absolute demand-supply balance for a specific skill basket in a specific country. It represents the number of active job postings per professional in that skill domain.

Formula
TR(s) = JP(s) ÷ TP(s)
Where TR(s) is the Tightness Ratio for skill basket s; JP(s) is the total active job posts matching at least one skill in basket s; TP(s) is the total professionals with at least one skill from basket s.
Worked example
AI & Data Science in Greece (May 2026)

JP(AI&DS) = 1,105 job posts; TP(AI&DS) = 64,865 professionals

TR(AI&DS) = 1,105 ÷ 64,865 = 0.01703 (1.7%)

Interpretation: there are approximately 1.7 job postings for every 100 AI & Data Science professionals in Greece — roughly one job post per 59 professionals.

4.2 Step 2 — Market Tightness Ratio (TR-Market)

The same calculation applied to the entire labor market in the country, with no skill filter. This serves as the universal benchmark.

Formula
TR(m) = JP(m) ÷ TP(m)
Worked example
Entire Greek market (May 2026)

JP(m) = 17,830 job posts; TP(m) = 1,773,314 professionals

TR(m) = 17,830 ÷ 1,773,314 = 0.01005 (1.0%)

4.3 Step 3 — Skills Demand-Supply Intensity (SDSI)

The SDSI expresses how tight a skill market is relative to the overall market, indexed to 100%. The overall market always equals 100%.

Formula
SDSI(s) = (TR(s) ÷ TR(m)) × 100%
Worked example
AI & Data Science
SDSI(AI&DS) = (0.01703 ÷ 0.01005) × 100% = 170%

Interpretation. The AI & Data Science skill market in Greece is 1.70× tighter than the overall labor market. For every job post per professional in the general market, there are 1.70 job posts per professional in AI & Data Science.

4.4 Rounding convention

All published SDSI values are rounded to whole percentages (e.g., 170%, not 169.5%). Tightness Ratios are reported as percentages rounded to one decimal place (e.g., 1.7%). Decimal places beyond these thresholds imply false precision given that LinkedIn counts fluctuate daily.

4.5 Score interpretation

The SDSI score is unbounded — it can range from near 0% to well above 250%. The following interpretation bands provide guidance for readers:

SDSI RangeInterpretation
Below 50%Significantly looser than market — oversupplied skill domain
50–80%Moderately looser than market
80–120%Near market average
120–180%Moderately tighter than market
180–250%Significantly tighter — talent scarcity signal
Above 250%Acute tension — severe demand-supply imbalance

These bands are initial estimates based on the first release. They will be reviewed and potentially adjusted after 6 months of cross-sectional data across multiple skill baskets.

5. Anchor / Baseline Protocol

5.1 Self-anchoring design

Unlike indices built on relative data sources (e.g., Google Trends), the SDSI Index is self-anchoring. The market-wide Tightness Ratio serves as the baseline and is recalculated fresh with every monthly release. A SDSI of 170% means 1.70× the market tightness right now, not relative to a historical reference period.

This eliminates several common methodological challenges: there is no anchor drift, no re-anchoring events, and no scale-factor instability. The index is always expressed in current-market terms.

5.2 Implications

Because the baseline is recalculated each period, month-over-month SDSI changes reflect shifts in relative position, not absolute levels. A skill basket's SDSI could decrease even if its absolute Tightness Ratio increased, provided the overall market tightened faster. The auxiliary Tightness Ratio (reported separately) provides the absolute context needed to distinguish these scenarios.

6. Auxiliary Metrics

6.1 Tightness Ratio (TR)

The Tightness Ratio is reported alongside each skill basket's SDSI score as an auxiliary metric. While the SDSI captures relative market position, the TR provides the absolute demand-supply signal.

Formula
TR(s) = JP(s) ÷ TP(s), expressed as a percentage

The combination of SDSI and TR enables a two-dimensional interpretation:

High SDSI (> 120%)Low SDSI (< 80%)
High TR
Genuine talent crunch
Tight market, tighter than average — the strongest scarcity signal.
Broad-market tightness
Overall market is tight; the skill is not specifically scarce.
Low TR
Relative scarcity in a soft market
Skill stands out despite loose overall conditions.
Unremarkable
Oversupplied skill in a loose market.

6.2 Market Tightness Ratio (TR-Market)

The overall market Tightness Ratio is reported as a standalone metric to provide macroeconomic context. It represents the economy-wide job-to-professional ratio and serves as the denominator for all SDSI calculations.

7. Data Collection

Each monthly release is built from a single LinkedIn Talent Insights snapshot per country, taken on a fixed collection date within the publication month. The same date applies to every basket in that country-month, so all values within a release are mutually consistent.

Two categories of measurement are recorded for each snapshot:

  • Market baseline. Total Professionals (TP-market) and Total Job Posts (JP-market) for the country with no skill filter applied. Collected once per country per month; serves as the denominator for every SDSI calculation in the release.
  • Per-basket measurement. For each of the 12 skill baskets, Total Professionals (TP(s)) and Total Job Posts (JP(s)) matching at least one skill in the basket. The OR-logic filter convention is described in Section 9.

From these inputs, the formulas in Section 4 yield TR(s), TR(m), and SDSI(s). All raw counts and derived values are archived alongside their collection date to build the forward-looking time series; recalculation of past values is never performed retroactively, since LinkedIn Talent Insights does not support historical queries.

8. Publication Format

8.1 Release components

  • Headline ranking table: all 12 skill baskets sorted by SDSI, with the SDSI value and a plain-language label from the interpretation bands
  • Auxiliary Tightness Ratios alongside each basket
  • Market Tightness Ratio as macroeconomic context
  • Trend chart showing SDSI over time per basket (from month 3 onward)
  • Intellectica commentary: 2–3 sentences highlighting the most notable movements or comparisons

8.2 Publication channels

The SDSI Index is published via an interactive dashboard on the Intellectica website, with supporting distribution via LinkedIn posts and an email digest.

8.3 Cadence

Monthly. Each release is published within the first week of the calendar month and reports the previous month's snapshot.

9. Limitations & Considerations

  • LinkedIn coverage bias. LinkedIn over-represents white-collar, urban, tech-adjacent professionals. SDSI values for knowledge-work skill baskets are reliable. For manual trades, hospitality, construction, or informal-economy skill domains, the underlying data is structurally incomplete. This defines the scope boundary of the index.
  • Snapshot, not flow. LinkedIn Talent Insights shows current stock of professionals and current open postings. It does not capture hiring velocity, time-to-fill, offer acceptance rates, or salary pressure. The SDSI measures structural tension, not hiring outcomes.
  • No historical baseline. LinkedIn Talent Insights provides current-state snapshots only. There is no way to query historical values for past dates. The index begins live from its launch date. No backtested values are produced or implied. The time series builds forward.
  • OR-logic skill filters. LinkedIn's skill filter uses OR logic — a professional with any one skill from the basket is counted. Broadly-skilled professionals therefore appear in multiple baskets simultaneously. Cross-basket SDSI values are not fully independent; they share talent-pool overlap.
  • Domain-essential skills inflate overlap. Skills included under the domain-essentiality principle (e.g., Python, SQL, Negotiation) are shared across multiple domains. This amplifies cross-basket talent-pool overlap. The effect is documented and monitored but does not invalidate within-basket SDSI calculations.
  • Daily fluctuation in counts. LinkedIn's professional and job-posting counts shift daily as profiles and postings are added or removed. Monthly snapshots mitigate this, but a single collection date introduces minor timing sensitivity.
  • Sensitivity to overall market conditions. Because the SDSI is benchmarked to the entire market, it is sensitive to macroeconomic shifts. If LinkedIn job-posting volume surges across all sectors, all skill-specific SDSI values will shift even if nothing changed in those specific skill markets. The auxiliary TR provides the absolute context needed to identify this effect.
  • Interpretation bands are initial estimates. The score-interpretation table is based on the first release and limited cross-sectional data. Bands will be reviewed and potentially recalibrated after 6 months of operation across all 12 skill baskets.
  • Thin-signal risk for certain baskets. Legal & Compliance and UX/UI & Product Design may have limited professional and job-posting counts in smaller markets. If a basket produces fewer than 50 job posts in a country, the SDSI is reported with an explicit low-confidence flag.

10. Versioning & Updates

10.1 Versioning convention

v1.x (minor versions). Adding or removing individual skills within an existing basket, adding a new skill basket, documentation improvements, cosmetic refinements. No structural impact on the SDSI formula or interpretation framework.

v2.0+ (major versions). Changes to the SDSI formula, modification of interpretation bands, changes to the market baseline definition, changes in publication frequency, fundamental redefinition of basket construction principles.

10.2 Component updates

Skill baskets are reviewed every 6 months. Triggers for component changes:

  • A skill shows decaying professional count or negligible job-posting activity over multiple consecutive periods
  • A new skill emerges with strong, continuous signal that fits an existing basket's domain
  • Technological or market shifts make a skill obsolete or fundamentally change its domain association
  • A dominant skill's with-and-without SDSI values diverge significantly, indicating distortive effect

10.3 Adding new skill baskets

Adding a new skill basket is a minor version event (v1.x) since it does not affect existing baskets or the SDSI formula. The new basket is simply added to the cross-sectional ranking from its first month of publication. No phased inclusion is required because each basket is independently calculated.

10.4 Major-version communication template

Template

"Starting this [month], the Skills Demand-Supply Intensity Index methodology has been updated. Specifically: [list of changes]. Previous periods have been recalculated under the new methodology where applicable. Full methodology change notes are available at [link]."

11. Roadmap

  • Cross-country expansion. Apply the framework to additional countries with their own market baselines, enabling comparison of skill-specific tension across geographies.
  • Interpretation-band recalibration. After 6 months of cross-sectional data, reassess the SDSI interpretation thresholds based on observed distributions across all 12 baskets.
  • Sub-basket analysis. Within large skill domains, explore sub-basket breakdowns (e.g., within AI & Data Science: Core ML vs. Generative AI vs. ML Infrastructure).
  • Additional baskets. Evaluate Green Energy & Sustainability, Data Engineering, and other domains as LinkedIn coverage and signal warrant.
  • Integration with Intellectica AI Pulse Index. Explore complementarity between the SDSI Index (talent-market tension) and AI Pulse Index (broader AI adoption and discourse signals).