Data Scientist Interview Questions

Bhavna S. - "Before diving into the Solution, I would ask a few clarifying questions. What is the scope of the fake news What type of fake news are we focusing on - Political, Health-related, etc Are we looking at specific examples or a general category of fake news When you say impact, what do you mean by that? Is it time spent on posts, the nature of the engagement (e.g., likes, shares, comments), and the sentiment of the comments? User Demographics: what is the demographic pr"See full answer

Alfred O. - "We can use dictionary to store cache items so that our read / write operations will be O(1). Each time we read or update an existing record, we have to ensure the item is moved to the back of the cache. This will allow us to evict the first item in the cache whenever the cache is full and we need to add new records also making our eviction O(1) Instead of normal dictionary, we will use ordered dictionary to store cache items. This will allow us to efficiently move items to back of the cache a"See full answer

Rajesh V. - "As a PM i received a feedback from my program manager on my style of verbal communication. It is about me speaking faster when i wanted to get away with a topic that i wasn't confident (may be not backed up with data, or still in process of getting detailed insight of a problem etc.). Whereas when I'm confident I tend to speak slowly or more assertively that made people to follow easily. I welcomed that feedback so from then on when I'm not confident in a topic I became more assertive to let pe"See full answer

Robert H. - "I use ChatGPT a lot to either refine my own answers or stories and make them better, or to answer questions which I would then refine to be more personal to me. Here's what ChatGPT says about this question: This question is testing your analytical thinking, data-driven decision-making, and product sense—especially in the context of Meta’s focus on engagement and content ranking. The best approach is to **define key engagement metrics, outline an experiment design, and consider trade-of"See full answer

Vysali K. - "Limit and rank() only works if there are no 2 employees with same salary ( which is okay for this use case) For the query to pass all the test results, we need to use dense_rank with ranked_employees as ( select id, firstname, lastname, salary, denserank() over(order by salary desc) as salaryrank from employees ) select id, firstname, lastname, salary from ranked_employees where salary_rank <= 3 `"See full answer

Bradley E. - "Here's a simpler solution: select u.username , count(p.postid) as countposts from posts as p join users as u on p.userid = u.userid where p.likes >= 100 group by 1 order by 2 desc, 1 asc limit 3 `"See full answer

Pratik H. - "You're a PM for Uber Eats. Cart conversion has dropped by 10% in the last 3 months. How would you find the root cause? Clarify- 1) What is conversion? Is it where they complete the order after adding it to cart?- Yes 2) Has this drop been sudden or over an extended period of time?- Its been over the past month 3) Is this localized to somewhere? Seems to be only in the US Uber Eats is a business that delivers food and various goods to customers that buy them. Its a 3 sided marketplace wher"See full answer

Himanshu G. - "To model ROI for a product launch, the first step is to define the timeline you're targeting Example 6 months post-launch, 1 year, or even 5 years. Tip: Start with a 1-year ROI projection to estimate near-term returns, and build a 3-year projection to evaluate growth and scalability. ROI is essentially the net return over that period: Profit=Revenue (within timeline)−Total Cost (from project start) Total Cost includes both fixed and variable costs incurred since t"See full answer

Gaston B. - "Use a representative of each, e.g. sort the string and add it to the value of a hashmap> where we put all the words that belong to the same anagram together."See full answer

Anonymous Prawn - "Would be better to adjust resolution in the video player directly."See full answer

Rohit K. - "First, let's align the Airbnb homepage with Airbnb's mission. Airbnb's mission is to "create a world where anyone can belong anywhere by providing healthy travel that is local, authentic, diverse, inclusive and sustainable." The homepage serves as the primary entry point for both potential guests and hosts, setting the stage for their journey and embodying this mission. Now, for the goals of Airbnb homepage, we can consider different aspects like awareness, engagement, and ultimately, driving bo"See full answer

Saurabh K. - "Missing Item - User ordered multiple items, few items are missing Wrong Item - Entire order is wrong / there are items in the order that were never ordered How is this measured ? CSAT Missing Items Wrong Items Step 1 : Collect data on orders that reported missing / wrong items. Dive deep to understand if the problem is isolated to a specific metro/zip code/restaurant type (say fast food vs fine dine), time of day (lunch vs dinner), tenure of the courier on th"See full answer

Anisha S. - "SELECT d.name as departmentname,e.id as employeeid,e.firstname,e.lastname,MAX(e.salary) as salary FROM employees e LEFT JOIN departments d ON e.department_id=d.id GROUP BY department_name ORDER BY department_name;"See full answer

theproductguy - "Clarifying Questions and possible responses: both audio and video goals: increase engagement time among groups/communitites and not require another platform to do group call (be one-stop for communication) region-TBD ios/android only available to users in a group to call users within the group who can intitiate these calls?- only admin? or anyone? metrics:NSM: feature engagement (C), number of calls made in a week per user (C). PM: % of people joining the call in a group"See full answer

Bhavna S. - "Step 1: Define Objectives and Key Metrics Objectives: Understand the demand for group video calling. Assess the potential impact on user engagement. Identify technical and user experience considerations. Key Metrics: Call Frequency: Number of 1:1 calls per user. Call Duration: Average duration of 1:1 calls. Call Participants: Identify users who frequently call multiple individuals. Concurrent Calls: Instances where users are engaged in multiple 1:1 call"See full answer

Soodong P. - "Product and Mission To allow users to create events and host on FB pages. It can be one time or recurring. It can include FB users through feeds or referrals or can be shared out with a link. Product objective is to build strong online and offline bonding through connecting people with common interests and ensure continued engagements. Aligns with the core Meta mission. User Journey and Value + Metrics Organizers: Finds the value when the many participants share interest or"See full answer

Aarav G. - "Is there a reason a confidence interval was used to solve this problem over just using the mean/expected value directly?"See full answer

Ranj A. - "In the Transformer architecture, the decoder differs from the encoder primarily in its additional mechanisms designed to handle autoregressive sequence generation. Here's a breakdown of the key differences: Self-Attention Mechanism: Encoder: The encoder has a standard self-attention mechanism that allows each token to attend to all other tokens in the input sequence. Decoder: The decoder has two types of self-attention. The first is the same as in the encoder, but the second is mas"See full answer