Data Scientist Interview Questions

XYZ - "We have observed that DAU have been declining, while MAU has remained constant. Activity is define as: Logging in. Viewing content. Posting content. Interacting with other users (likes, comments, etc.). Daily Active Users (DAU): This measures the number of unique users who engage with Instagram on a daily basis. It indicates how frequently users interact with the platform and reflects its daily stickiness. Monthly Active Users (MAU): This measures the number of unique users who en"See full answer

Malay K. - "For any project based questions, it is important to structure your response clearly, showcasing your thought process, technical skills, problem-solving abilities, and how your work added value. Besides the STAR method, you can also use this kind of framework: 1. Start by selecting a relevant project (related to the role) Give the project background and what specific problem it solved. 2. Align the project's objective and your role Be specific about your role: were you the le"See full answer

Sravanthi M. - "public static boolean isPalindrome(String str){ boolean flag = true; int len = str.length()-1; int j = len; for(int i=0;i<=len/2;i++){ if(str.charAt(i)!=str.charAt(j--)){ flag = false; break; } } return flag; }"See full answer

Steve Y. - "Define: How is daily post view calculated Isolate Issues: Data issue Time period Geo IOS vs Android vs Web Correlated Metrics in the funnel DAU Time spent/ scrolls Engagement - likes, comments External factors Competitor actions Big events Internal factors Product launch Feature change"See full answer

VContaineers - " Compare alternate houses i.e for each house starting from the third, calculate the maximum money that can be stolen up to that house by choosing between: Skipping the current house and taking the maximum money stolen up to the previous house. Robbing the current house and adding its value to the maximum money stolen up to the house two steps back. package main import ( "fmt" ) // rob function calculates the maximum money a robber can steal func maxRob(nums []int) int { ln"See full answer

Nagasowjanya V. - "Click- through rate (CTR) should not be analyzed in isolation. Combining it with watch time, bounce rate, and retention metrics ensures a comprehensive understanding of user engagement and content effectiveness. Hypothetically, addressing the 10% CTR decline on Netflix Understand & Identify where the CTR drop is: Compare CTR trends over the past few weeks / months / years to identify if this a seasonal fluctuations or a major issue. Is the 10% drop a platform-wide issue or specific to a"See full answer

Hayatu H. - "How do you find consecutive days for login (MySQL, SQL, date, subquery, MySQL 5.7, development)? 1 Follow Request Answer More All related (34) Recommended 📷 Trausti Thor Johannsson · Follow Been using MySQL for more than 16 yearsDec 27 There are functions like DATEDIFF but there are also BETWE"See full answer

Bala G. - "SELECT s.Sale_Date, SUM(si.Quantity * si.SalePrice) AS TotalRevenue FROM Sales s JOIN SaleItems si ON s.SaleID = si.Sale_ID GROUP BY s.Sale_Date ORDER BY s.Sale_Date; "See full answer

Raj V. - "CreditGO Loan App Customer-Care Number =(O)}((+917439822246=))℅+/{+O 9346281901+} CALL Now ·CreditGO Loan App Customer-Care Number =(O)}((+917439822246=))℅+/{+O 9346281901+} CALL Now ·CreditGO Loan App Customer-Care Number =(O)}((+917439822246=))℅+/{+O 9346281901+} CALL Now ·CreditGO Loan App Customer-Care Number =(O)}((+917439822246=))℅+/{+O 9346281901+} CALL Now ·"See full answer

William D. - "Clarify: I'm assuming that a workplace chat app is similar to something like Slack or Teams, which is a web app/mobile platform for employees to securely message each other directly or in a grouping (i.e. a channel). I'm also assuming that this workplace app is for a generic company, and not Microsoft or Salesforce. Goals: Workplace apps serve a vital connective tissue within enterprises to allow employees to freely message one another and collaborate on projects. These services a"See full answer

Alexey T. - "with t1 as (select customer_id, order_date, order_id, rownumber() over (partition by customerid, orderdate order by orderid) as order_rnk, count(orderid) over (partition by customerid, orderdate) as totalorders_day from orders) select customer_id, order_date, orderid as secondearliestorderid from t1 where totalordersday>=2 and order_rnk = 2 order by order_date, customer_id "See full answer

Astro S. - "What are they looking for in the answer? "See full answer

Anonymous Shark - "Clarify: Are we talking about traditional noise-cancelling which cancels noise for listeners or we are talking about the speaker side noise-cancellation? - Interviewer replied: Both Are we exploring to build something on top of existing hardware around Meta VR products or something in general? - Interviewer replied: up to you. High level though process (Could be detailed with more structure): Considering Meta's vision on building metaverse, where meta currently has AR/VR products li"See full answer

fuzzyicecream14 - "1. Sales & Revenue Metrics Total Units Sold – Tracks overall headset sales volume. Revenue Growth (%) – Measures whether revenue is increasing from headset sales over time. Sales by Channel – Identifies how sales are distributed across Google Store, third-party retailers (Amazon, Best Buy), and carrier partnerships. Sales by Region – Helps understand geographic demand and refine regional marketing efforts. Attach Rate – Measures how often the headset is purc"See full answer

Bala G. - "WITH ActiveUsersYesterday AS ( SELECT DISTINCT user_id FROM user_activity WHERE activity_date = CAST(GETDATE() - 1 AS DATE) ), VideoCallUsersYesterday AS ( SELECT DISTINCT user_id FROM video_calls WHERE call_date = CAST(GETDATE() - 1 AS DATE) ) SELECT (CAST(COUNT(DISTINCT v.userid) AS FLOAT) / NULLIF(COUNT(DISTINCT a.userid), 0)) * 100 AS percentagevideocall_users FROM ActiveUsersYesterday a LEFT JOIN VideoCallUsersYesterday v ON a.userid = v.userid;"See full answer

Umang S. - "Context - I joined a large public-facing service as a PM midway through its development. Situation - Due to the SOPs of the company the team already had a metrics framework. That included your standard DAUs, Retention and Acquisition Metrics Concern - As SOP metrics were publicly accepted, the team did not internalise what success actually means to the product they are developing, as the actual value was not being encapsulated in the framework This was evident in the show and tells as the"See full answer

David I. - "WITH filtered_posts AS ( SELECT p.user_id, p.issuccessfulpost FROM post p WHERE p.postdate >= '2023-11-01' AND p.postdate < '2023-12-01' ), post_summary AS ( SELECT pu.user_type, COUNT(*) AS post_attempt, SUM(CASE WHEN fp.issuccessfulpost = 1 THEN 1 ELSE 0 END) AS post_success FROM filtered_posts fp JOIN postuser pu ON fp.userid = pu.user_id GROUP BY pu.user_type ) SELECT user_type, post_success, post_attempt, CAST(postsuccess AS FLOAT) / postattempt AS postsuccessrate FROM po"See full answer

Abhinav M. - "Always assume good intentions on the part of both parties when resolving conflicts. Then proceed with a STAR example."See full answer

Vishal S. - "Product Understanding - Ads are what you see from companies as stories, posts, reels. Post are from users (connections). We have to design an experience which produces maximum engagement while generating ad revenue. Clarifying Questions - Is it specific to posts/stories/reels ? Is there an existing post to ads ratio or do we have to start from scratch? Is it specific to a device/OS? Is it specific to a region/user demographic? Assumption - Existing posts to ads ratio"See full answer

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