مهارات خاصة بالوظيفة

Data wrangling test for hiring

See how candidates prepare and check data before it is used for analysis.

10 دقيقة
15 سؤالًا
Intermediate
Multiple choice
Questions in الإنجليزية
Phone and desktop

Use this test free See the question formats

الإجابة المختصرة

The Data Wrangling test measures how candidates pull fields out of files and text, fix messy values, reshape and join tables, and check the result, working from small tables and short Python with pandas or standard SQL. It suits intermediate data analysts, data scientists, data engineers, reporting developers and machine learning engineers who prepare their own data.

ما الذي يقيسه

Parsing, cleaning, reshaping, joining and checking data for analysis, read from small tables and short code.

Extraction and parsing

Candidates work out how to pull fields from files and text.

Data cleaning

Candidates identify steps that fix messy data values.

Reshaping and combining

Candidates reason about reshaping tables and combining them through joins.

Data quality checks

Candidates check whether prepared data is ready for someone to rely on.

Question formats

Multiple choice

The candidate: Reads a short situation, table or statement and picks the right answer, or every right answer.

You see: Whether the candidate knows the material well enough to apply it, not just recognize it.

15 questions in 10 minutes, served one at a time.

Roles this test fits

Data analysts, data scientists, data engineers, analytics and reporting developers, data warehouse staff, and machine learning engineers who prepare their own data.

What this test can show

Judgment on messy records
See how candidates fix values in business records such as orders, sensor readings and shipments.
Reasoning from code and tables
Questions ask what a short step in Python with pandas or standard SQL produces, or which step would fix a problem.
Checks before anyone relies on it
Data quality questions show whether a candidate checks a cleaned or combined table before others build analysis on it, rather than trusting the step that produced it.

What you get for each candidate

Example report (fictional data)Data Wrangling

74‎%‎Percentile 53. Benchmark: HireValid candidates, n = 371

Extraction and parsing73‎%‎

Data cleaning76‎%‎

Reshaping and combining55‎%‎

Data quality checks90‎%‎

Integrity Scoreثقة عالية

Stayed on the test tab throughout
No pasted answers
Answered at a steady pace

Scores, profiles and integrity signals are evidence for you to review alongside an interview, never an automatic decision.

Use this test free

Test integrity signals

Each candidate receives a different set of questions from large question pools. Questions appear in a different order for each attempt, and answer options are shuffled. The browser receives one question at a time, and answer keys stay on HireValid’s servers. Timing runs on the server, so reloading restores the same question with only the time left. Question text cannot be copied or selected. HireValid records signals such as time away from the test tab, pastes into answers, and answers faster than a question can be read. These are summarized in an Integrity Score with an evidence timeline for you to review; the score does not decide on its own. With candidate consent, you can add webcam photos at random moments. See how we build our tests.

كيف نمنع الغش باستخدام الذكاء الاصطناعي · Integrity signals

Use the score as evidence

Review the score alongside a work sample that asks candidates to prepare and check data relevant to the role. A structured interview can explore their choices. Treat the test as one source of evidence, not a verdict. For related context, compare it with the Data Extraction, Transformation, and Loading (ETL), Data Science, or Pandas test.

أسئلة المقابلة المنظّمة

Tell me about a time you had to prepare messy data for analysis. How did you decide what to fix?
Listen for a clear account of the data issue, the cleaning choices, and how the candidate checked the result.
How would you investigate a table that needs to be combined with another before analysis?
Listen for how they would inspect the tables, decide how to join them, and check the combined result.
Describe a data quality problem you found before others used the data. What did you do next?
Listen for the check they used, how they traced the issue, and how they handled the affected data.

Understand scoring and benchmarks

Fairness and accommodations

Questions use neutral business records such as orders, sensor readings, sign-ups and shipments. Names come from many backgrounds, and there are no money symbols, idioms or local knowledge. Dates are written in year-month-day form unless a question is about date formats. The code is short and uses widely taught features of Python with pandas and standard SQL. It avoids behavior that differs between library versions or database products, so the test measures wrangling judgment rather than one tool's quirks. Scratch paper is allowed for every candidate, and no question needs a calculator.

You can give any candidate extra time as an accommodation. Results are evidence for a person to review, never an automatic decision.

Provisional: reliability is reported once 200 candidates have completed it.

اقرأ نهجنا في الإنصاف

Test details

A short, timed test of getting data ready for analysis. Candidates pull fields out of files and text, fix messy values, reshape and combine tables, and check the result before anyone relies on it. Questions show small tables and short snippets of Python with the pandas library or standard SQL, and ask what a step produces or which step fixes a problem.

Questions are in English.
Aids allowed: Scratch paper.
Each question is answered once, in order, with no going back.
4 practice questions, 3 minutes, before the timed test.

Python, pandas are trademarks of their owners. HireValid is not affiliated with or endorsed by them.

الأسئلة الشائعة

Who should take the Data Wrangling test?+

It is intended for intermediate data analysts, data scientists, data engineers, analytics and reporting developers, data warehouse staff, and machine learning engineers who prepare their own data. It fits people who clean and reshape data themselves, not only those who analyze it.

How does the Data Wrangling test handle fairness?+

Questions use neutral business records such as orders, sensor readings, sign-ups and shipments. Names come from many backgrounds, there are no money symbols, idioms or local knowledge, and dates use year-month-day form unless a question is about date formats. The code uses widely taught features of Python with pandas and standard SQL, and avoids behavior that differs between library versions or database products, so it measures wrangling judgment rather than one tool’s quirks.

Can candidates use scratch paper on the Data Wrangling test?+

Yes. Scratch paper is allowed for every candidate, and no question needs a calculator. Candidates can also try a practice set of 4 questions that takes 3 minutes before the 10-minute test.

Can candidates go back or take the Data Wrangling test on a phone?+

The test runs on a phone or a desktop. Each of the 15 questions is answered once, in order, with no going back, so a candidate decides what a pandas or SQL step produces before moving on. Some questions have one correct answer and others ask candidates to select every option that applies.