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Practising for the listing Staff Data Scientist, Ads. Its requirements are filled in below. When you have an answer you like, paste it with your CV in Career Mirror to see which of the job's skills it shows.

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Staff Data Scientist, Ads
Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 130 million daily active unique visitors, Reddit is one of the internet’s largest sources of information. For more information, visit www.redditinc.com .

Location: US remote-friendly

Reddit has a flexible first workforce. At Reddit we continue to grow our teams with the best talent. We're completely remote friendly and will continue to be.

Advertising is Reddit’s primary revenue driver and we have an ambitious goal to turn it into a massive business. Although several large digital ad platforms already exist, advertisers are being increasingly drawn to Reddit because of our passionate communities. We believe our community-centric platform has created the opportunity for Reddit to build a highly differentiated ads business.

About the Ads Data Science Team:

The Ads Data Science team at Reddit leverages data to maximize advertiser value on Reddit through robust data foundations, metrics, and strategic insights generated through experimentation and cutting-edge DS methods.

We work on a wide range of challenging problems in the areas of ads and platform measurement, campaign and creative management, advertiser growth and retention, monetization, and the intersection of brand and community engagement. We are a highly collaborative team of passionate data scientists and engineers who are constantly pushing the boundaries of what's possible with machine learning and statistical modeling.

About the Role:

Reddit’s Ads Data Science team is looking for a highly experienced Staff Data Scientist to advance the intelligence powering the advertiser experience on Reddit. In this role, you'll take deep ownership of a high-impact problem space within advertising, specializing in measurement, identity, and signal quality.

This is a high-impact, high-autonomy role where you'll influence strategic direction, set a high technical bar, and drive cross-functional initiatives across one or more critical focus areas in the Ads organization.

Responsibilities:

• Design the Future of Ads Identity: Develop/employ probabilistic models for identity resolution. Design the methodology that links on-platform and off-platform actions to maximize addressability while honoring privacy.

• Advance Lift Methodologies & Experimentation: Own the statistical rigor behind Reddit’s Brand and Conversion Lift products. Innovate experimental design and develop infrastructure that supports large-scale, high-velocity, low-bias testing for advertisers.

• Maximize Signal for Predictive Performance: Define the strategy for new signal sources. You will mathematically quantify the value of these signals and work with modeling teams to incorporate them into predictive models, directly improving bidding efficiency and ROAS.

• Define Ground Truth & Evaluation Frameworks: Solve the industry-wide challenge of validating identity and measurement. Design the objective functions and truth sets used to train our models and measure the incremental impact of our identity graph.

• Lead Through Cross-Functional and Technical Influence: Collaborate deeply with engineering, product, and sales to align on strategic goals, translate insights into action, and drive execution. Set a high technical bar by mentoring others and championing best practices across modeling, experimentation, and measurement.

Qualifications:

• Required:

• Advanced degree (Master's or Ph.D.) in Statistics, Mathematics, Physics, Economics, or Operations Research

• For M.S. holders: 10+ years of industry experience in applied science or data science roles

• For Ph.D. holders: 6+ years of industry experience in applied science or data science roles

• Deep understanding of the ads ecosystem

• Demonstrated expertise in at least one of the following areas:

• Measurement & Experimentation at Scale (with focus on lift and attribution)

• Identity Graph Creation & Resolution Methodology and Infrastructure

• Predictive Modeling with Signal Loss

• Advanced proficiency in statistical programming (Python or R) and SQL

• Experience with machine learning or optimization techniques

• Strong understanding of experimental design, causal inference, or A/B testing methodologies

• Exceptional problem-solving and communication skills, with a track record of influencing product and engineering partners

• Experience working in fast-paced, ambiguous environments with cross-functional teams

Benefits:

• Comprehensive Healthcare Benefits and Income Replacement Programs

• 401k with Employer Match

• Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support

• Family Planning Support

• Gender-Affirming Care

• Mental Health & Coaching Benefits

• Flexible Vacation & Paid Volunteer Time Off

• Generous Paid Parental Leave

#LI-Remote
Pay Transparency:

This job posting may span more than one career level.

In addition to base salary, this job is eligible to receive equity in the form of restricted stock units, and depending on the position offered, it may also be eligible to receive a commission. Additionally, Reddit offers a wide range of benefits to U.S.-based employees, including medical, dental, and vision insurance, 401(k) program with employer match, generous time off for vacation, and parental leave. To learn more, please visit https://www.redditinc.com/careers/ .

To provide greater transparency to candidates, we share base salary ranges for all US-based job postings regardless of state. We set standard base pay ranges for all roles based on function, level, and country location, benchmarked against similar stage growth companies. Final offer amounts are determined by multiple factors including, skills, depth of work experience and relevant licenses/credentials, and may vary from the amounts listed below.

The base salary range for this position is:
$217,000 — $303,900 USD

In select roles and locations, the interviews will be recorded, transcribed and summarized by artificial intelligence (AI). You will have the opportunity to opt out of recording, transcription and summarization prior to any scheduled interviews.

During the interview, we will collect the following categories of personal information: Identifiers, Professional and Employment-Related Information, Sensory Information (audio/video recording), and any other categories of personal information you choose to share with us. We will use this information to evaluate your application for employment or an independent contractor role, as applicable. We will not sell your personal information or disclose it to any third party for their marketing purposes. We will delete any recording of your interview promptly after making a hiring decision. For more information about how we will handle your personal information, including our retention of it, please refer to our Candidate Privacy Policy for Potential Employees and Contractors .

Reddit is proud to be an equal opportunity employer, and is committed to building a workforce representative of the diverse communities we serve. Reddit is committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If, due to a disability, you need an accommodation during the interview process, please let your recruiter know.

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Requirements found

Training Sales Sql (must) Python (must) Scheduling Marketing

What this posting asks for

Level: Lead / staff — The title says "Staff".

Main responsibilities

Design the Future of Ads Identity: Develop/employ probabilistic models for identity resolution. Design the methodology that links on-platform and off-platfor…
Advance Lift Methodologies & Experimentation: Own the statistical rigor behind Reddit’s Brand and Conversion Lift products. Innovate experimental design and …
Maximize Signal for Predictive Performance: Define the strategy for new signal sources. You will mathematically quantify the value of these signals and work …
Define Ground Truth & Evaluation Frameworks: Solve the industry-wide challenge of validating identity and measurement. Design the objective functions and tru…
Lead Through Cross-Functional and Technical Influence: Collaborate deeply with engineering, product, and sales to align on strategic goals, translate insight…

Competencies an interviewer will look for

Technical skill Core
In the posting: “Lead Through Cross-Functional and Technical Influence: Collaborate deeply with engineering, product, and sales to align on strategic goals, translate insight…” · “Advanced proficiency in statistical programming (Python or R) and SQL” · “Exceptional problem-solving and communication skills, with a track record of influencing product and engineering partners”
Show it by: Names the tools, languages or systems used and how; Explains a technical choice and its trade-off.
Teamwork and collaboration Core
In the posting: “We are a highly collaborative team of passionate data scientists and engineers who are constantly pushing the boundaries of what's possible with machine lear…” · “This is a high-impact, high-autonomy role where you'll influence strategic direction, set a high technical bar, and drive cross-functional initiatives across…” · “Lead Through Cross-Functional and Technical Influence: Collaborate deeply with engineering, product, and sales to align on strategic goals, translate insight…”
Show it by: Says what they did inside a team, not only what 'we' did; Shows how a disagreement was handled.
Ownership and accountability Core
In the posting: “In this role, you'll take deep ownership of a high-impact problem space within advertising, specializing in measurement, identity, and signal quality.” · “This is a high-impact, high-autonomy role where you'll influence strategic direction, set a high technical bar, and drive cross-functional initiatives across…” · “Advance Lift Methodologies & Experimentation: Own the statistical rigor behind Reddit’s Brand and Conversion Lift products.”
Show it by: Takes a task from start to finish without being chased; Owns a mistake and what was changed after it.
Planning and organisation Core
In the posting: “This is a high-impact, high-autonomy role where you'll influence strategic direction, set a high technical bar, and drive cross-functional initiatives across…” · “Experience working in fast-paced, ambiguous environments with cross-functional teams” · “Family Planning Support”
Show it by: Shows how priorities were set when everything was urgent; Mentions deadlines met and how.
Data and analysis Core
In the posting: “About the Ads Data Science Team:” · “The Ads Data Science team at Reddit leverages data to maximize advertiser value on Reddit through robust data foundations, metrics, and strategic insights ge…” · “We are a highly collaborative team of passionate data scientists and engineers who are constantly pushing the boundaries of what's possible with machine lear…”
Show it by: Uses a number to describe the situation or the result; Explains what the data showed and what was done with it.
Adaptability and learning Core
In the posting: “Reddit has a flexible first workforce.” · “Experience working in fast-paced, ambiguous environments with cross-functional teams” · “Flexible Vacation & Paid Volunteer Time Off”
Show it by: Describes learning something new quickly and using it; Shows a change of plan and how they adjusted.
Attention to detail and quality Core
In the posting: “In this role, you'll take deep ownership of a high-impact problem space within advertising, specializing in measurement, identity, and signal quality.” · “Innovate experimental design and develop infrastructure that supports large-scale, high-velocity, low-bias testing for advertisers.” · “Strong understanding of experimental design, causal inference, or A/B testing methodologies”
Show it by: Gives an example of an error caught before it caused harm; Names the check or standard they used.
Stakeholder management Core
In the posting: “This is a high-impact, high-autonomy role where you'll influence strategic direction, set a high technical bar, and drive cross-functional initiatives across…” · “Lead Through Cross-Functional and Technical Influence: Collaborate deeply with engineering, product, and sales to align on strategic goals, translate insight…” · “Exceptional problem-solving and communication skills, with a track record of influencing product and engineering partners”
Show it by: Shows how they aligned people with different goals; Explains how they handled a 'no' from someone senior.
Problem solving Core
In the posting: “Define Ground Truth & Evaluation Frameworks: Solve the industry-wide challenge of validating identity and measurement.” · “Exceptional problem-solving and communication skills, with a track record of influencing product and engineering partners”
Show it by: Describes a real problem, the options considered and the one chosen; Shows how the cause was found, not just the fix.
Leadership and mentoring Core
In the posting: “Set a high technical bar by mentoring others and championing best practices across modeling, experimentation, and measurement.” · “Mental Health & Coaching Benefits”
Show it by: Describes setting direction or a standard others followed; Names someone they coached and what changed for them.
Communication Supporting
In the posting: “Exceptional problem-solving and communication skills, with a track record of influencing product and engineering partners”
Show it by: Adapts the message to the listener; Gives an example of explaining something clearly in writing or speech.

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Practice questions

Tell me about yourself. Dedicated step-by-step practice.
If an interviewer asks something improper How to respond to questions about age, family, origin or health.
Built from this posting (8):
Walk me through a piece of work where you used your strongest technical skill. What exactly did you do? From this posting
Describe a time you worked with another team to deliver something. What was your part? From this posting
Tell me about a task you took from start to finish without anyone asking you to. From this posting
You have three urgent tasks due today and time to finish only two. How do you decide? From this posting
How have you used sql in your work? Walk me through one real example. From this posting
Tell me about a problem you solved using python. From this posting
Tell me about a time you helped someone on your team get better at their work. From this posting
Tell me about a time you had to explain something complex to someone outside your field. From this posting
This posting reads as Data analysis: its questions come first.
Tell me about an analysis that changed a decision. Data analysis
How do you check that a query or spreadsheet you built gives the right answer? Data analysis
Describe a new tool or technique you learned to finish a piece of work. Data analysis
Describe a time you found that the data you were given was wrong. Data analysis
A manager asks you for 'the numbers' by tomorrow with no further detail. What do you do? Data analysis
What makes a dashboard useful, and how have you built one? Data analysis
Tell me about a time you explained a statistical result to people without a data background. Data analysis
Sales dropped 15% last month. How would you find out why? Data analysis
Two managers ask you to book the same room at the same time. What do you do?
Tell me about a sale or agreement you are proud of.
Walk me through how you would check whether a report's numbers are right.
Describe a time you handled an upset customer or colleague.
Tell me about a time you had several deadlines at once. How did you decide what to do first?
Give an example of a mistake you caught before it caused a problem.
Tell me about a time you taught someone how to do something.
Describe a time you took the lead without being asked.
Tell me about a time you had to explain something complicated in simple terms.
Describe a process you improved.
Do you have any questions for us?
Why do you want to work here?
Why is there a gap in your employment? Difficult question
Why did you leave your last job? Difficult question
Why are you changing careers? Difficult question
What is your greatest weakness? Difficult question
What are your salary expectations? Difficult question
You seem overqualified for this role. Why do you want it? Difficult question
Improper-question practice: How old are you? / Do you have children? / Where are you from originally?
A customer is angry about a delay you did not cause. What do you do?
How do you keep track of many open customer requests?
Tell me about a time you could not give a customer what they wanted.
You find that the inventory count does not match the system. What do you do?
Tell me about a time a shipment or delivery went wrong.
How do you make sure safety rules are followed on a busy shift?
How have you used spreadsheets in your work?
Tell me about a time you had to enter or check a lot of data accurately.
A prospect says your price is too high. How do you respond?
How do you keep your pipeline organised?
Tell me about a technical problem you solved on your own.
You find a bug right before a release. What do you do?