WEIAN DATA 惟安数据科技
WEIAN DATA — DATA SCIENCE FOR MEASUREMENT & LARGE-SCALE SURVEYS

Exam, assessment & survey data, made into trustworthy conclusions.

From data cleaning and defensible scoring to reports and software tools, we solve the hardest data problems in exams, assessments, and surveys — for universities, testing agencies, government programs, and companies.
You bring the question; we deliver results that are trustworthy, reproducible, and audit-ready.

Book a free assessment →
INPUT · RAW RESPONSE DATA
IRT MODELING · EQUATING · WEIGHTING
OUTPUT · TRUSTWORTHY CONCLUSIONS
n = 0
● LIVE PIPELINE
106
MILLION-RECORD PROCESSING
0
IN-HOUSE TOOLS · FULL IP OWNERSHIP
0+
AUTOMATED TEST SUITES
0%
DATA STAYS IN YOUR INTRANET
01 — SERVICES

Three kinds of problems we solve

New to IRT, equating, or weighting? That's fine — in every project, we explain each step until it makes sense to you. To read ahead, Methods explains every method in language you can understand, and the Learning Hub offers a systematic beginner's path.

/ 01 Data processing & measurement modeling Scores that stay comparable across test forms, questionnaires scored defensibly, millions of responses processed fast and right — we handle every step from raw data to final scores and reports. Testing / Education / Research
/ 02 Long-term methodology advisor Missing someone who can vouch for your methods? From study design and tricky data problems to result review — retain us by project or by year and ask anytime, like an extra technical partner on staff. Research groups / Sponsors / Government
/ 03 Software & analysis tool development We turn the analysis you repeat every year into software your own team can run: standardized pipelines, consistent results, documented and tested — no longer dependent on any one person. Scales / Corporate assessment / Internal tools

Sound familiar?

UNIVERSITIES & RESEARCH

A reviewer questioning your measurement model? Unsure about weighting, missing data, or reliability? We work to academic standards and hand over every method, parameter, and step — ready for peer review and defense.

TESTING & EDUCATIONAL ASSESSMENT

Need scores that are truly comparable across sessions and test forms? Ready to move beyond raw totals to modern, defensible scoring? Million-record response data too heavy to process? This is our core business.

GOVERNMENT & PUBLIC INSTITUTIONS

A large survey or monitoring program that needs a reliable third party for data processing and quality control? We deliver fully reproducible pipelines — every number traceable, audit-ready, and your data never leaves your intranet.

COMPANIES

Want talent assessments with defensible scores and norms rather than simple totals? Employee and customer surveys that yield decisions rather than piles of charts? We turn data into results your leadership can act on.

02 — SECURE DELIVERY

Your data never leaves. The tools stay precise.

Sensitive data that cannot be handed to an outside team is where many projects stall. Our tool–data isolation model was designed for exactly this: WEIAN never touches your real data — we build the tools on de-identified samples, and all real-data computation happens inside your intranet. You get verifiable results; your data never takes a single step outside.

WEIAN · DEV ENVIRONMENT
TOOL
Project-specific analysis kernel
built on de-identified samples
TOOL-ONLY DELIVERY
CLIENT INTRANET · DATA NEVER LEAVES
Real data runs inside your intranet
verifiable · reproducible
STEP 1
You provide the schema
Only a data schema and de-identified sample records — no real record ever leaves your environment.
STEP 2
WEIAN builds the tool
From the de-identified samples, we rapidly develop and refine a project-specific analysis kernel with AI.
STEP 3
You run it in-house
The tool is delivered to your secure side; real-data execution stays in your intranet, with verifiable results.
* Contract and NDA signed before work begins; the de-identification scope is confirmed with you in writing.
03 — IN-HOUSE TOOLS

Methods, distilled into reusable software

Three in-house software tools covering the full cleaning → scoring → weighting workflow for survey and assessment data, with complete IP ownership — what you receive is not a one-off script, but an engineered product built to last.

View full case studies →
DCC
Data cleaning

Automated checking, correcting, and merging — every change logged and traceable, so silent data errors never reach your results.

Full case study →
IRTC
Measurement modeling

A high-performance scoring engine for millions of responses, keeping scores comparable across test forms and years.

Full case study →
WFC
Survey weighting

Makes sample surveys truly represent the population: pre-checks, calibration, and diagnostics in one workflow.

Full case study →
04 — PROCESS

From one email to milestone delivery

01
Reach out
Email us a short note about your project — a rough description is enough to start.
02
Free assessment
We tell you, for free, whether it can be done and how we would do it.
03
Proposal & quote
Scope, timeline, and price in writing — and what's out of scope stated up front. No gray areas.
04
Contract & NDA
A formal contract and confidentiality agreement with a registered company; invoices included.
05
Milestone delivery
Work arrives in stages, each with code, results, and documentation. You pay after you accept.
Production-grade code
Runnable, commented Python/R code.
Reproducible pipelines
Same input, same output — every step auditable.
Complete documentation
Manuals and technical notes your team can take over.
Automated tests
Key computations ship with test suites.
Rasch / 2PL / GPCM · Multidimensional IRT · EAP estimation · Equating & linking · DIF analysis · Calibration weighting (QP) · Unit merging (MILP) · CTT reliability · Automated reporting · R package development · Rcpp / C++ · Python data engineering ·  Rasch / 2PL / GPCM · Multidimensional IRT · EAP estimation · Equating & linking · DIF analysis · Calibration weighting (QP) · Unit merging (MILP) · CTT reliability · Automated reporting · R package development · Rcpp / C++ · Python data engineering · 

Your data project deserves a free assessment.

An exam, an assessment, or a large-scale survey — email us the background and goals. We'll first tell you honestly whether it's feasible and worth doing, then send a technical plan and quote. The initial consultation is free, and if we're not the right fit, we'll say so.

Email us → contact@weiandata.com