Data Scientist Interview Questions

Kanishkan V. - "I responded with a project that I was a part of during my capstone class. I described how I used HTML, Python, and PostGRESQL in conjunction to create a functioning website using SCRUM."See full answer

Vineet M. - "The distribution of daily minutes spent on Facebook per user is heavily right-skewed with a long tail. Most users spend a short amount of time while a smaller segment of heavy users push up the average with 2–3+ hours daily."See full answer

Constantin P. - "Reinforcement Learning is a type of machine learning where an agent learns to make decisions by trying out different actions and receiving rewards or penalties in return. The goal is to learn, over time, which actions yield the highest rewards. There are three core components in RL: The agent — the learner or decision-maker (e.g., an algorithm or robot), The environment — everything the agent interacts with, Actions and rewards — the agent takes actions, and the environmen"See full answer

Meenakshi D. - "BETWEEN and HAVING clauses in SQL serve different purposes: 1. BETWEEN Clause Used to filter rows based on a range of values. Works with numeric, date, or text values. Can be used with WHERE or HAVING clauses. The range includes both lower and upper bounds. Example: Filtering employees with salaries between 30,000 and 50,000 `SELECT * FROM Employees WHERE salary BETWEEN 30000 AND 50000;` 2. HAVING Clause Used to filter **groups"See full answer

Guilherme F. - "A much better solution than the one in the article, below: It looks like the ones writing articles here in Javascript do not understand the time/space complexity of javascript methods. shift, splice, sort, etc... In the solution article you have a shift and a sort being done inside a while, that is, the multiplication of Ns. My solution, below, iterates through the list once and then sorts it, separately. It´s O(N+Log(N)) class ListNode { constructor(val = 0, next = null) { th"See full answer

Rishi G. - "Problem Statement: The Fibonacci sequence is defined as F(n) = F(n-1) + F(n-2) with F(0) = 1 and F(1) = 1. The solution is given in the problem statement itself. If the value of n = 0, return 1. If the value of n = 1, return 1. Otherwise, return the sum of data at (n - 1) and (n - 2). Explanation: The Fibonacci sequence is a series of numbers where each number is the sum of the two preceding ones, typically starting with 0 and 1. Java Solution: public static int fib(int n"See full answer

Saipranay M. - "During the early learning stages of my career as a data scientist, I struggled to fully grasp the concept of patterns in seemingly random events. Despite thorough research, I remained skeptical about the universality of this idea. However, my perspective changed during a surprising scuba diving experience while on vacation. The underwater world I encountered not only amazed me but also gave me a key insight into patterns in nature and data analysis. As I dove into the clear waters, I witnessed"See full answer

Ali H. - "SQL databases are relational, NoSQL databases are non-relational. SQL databases use structured query language and have a predefined schema. NoSQL databases have dynamic schemas for unstructured data. SQL databases are vertically scalable, while NoSQL databases are horizontally scalable."See full answer

Dev S. - "Clarfying questions : When we say a decrease in users adding the bank accounts. I would like to understand how the users making payments within Venmo I assume they are either using their credit cards/debit cards? I would like to understand why the Adding of Bank Accounts is integral to Venmo since the users are using the debit card and Credit Cards. My understanding is when the payments happen through debit cards rails Venmo pays higher interchange fees and to Reduces any losses incurred"See full answer

Ilnur I. - "I can try to summarize their discussion as I remembered. Linear regression is one of the method to predict target (Y) using features (X). Formula for linear regression is a linear function of features. The aim is to choose coefficients (Teta) of the prediction function in such a way that the difference between target and prediction is least in average. This difference between target and prediction is called loss function. The form of this loss function could be dependent from the particular real"See full answer

Surbhi G. - "Deep Learning is a part of Artificial Intelligence, it's like teaching the machine to think and make decisions on its own. It's like how we teach a child the concept of an apple - it's round, red, has a stem on top. We show them multiple pictures of apples and then they understand and can recognize an apple in future. Similarly, we feed lots of data to the machine, and slowly, it starts learning from that data, and can then make relevant predictions or decisions based on what it has learnt. A co"See full answer

rkk293 - "How would you increase the number of comments on groups?"See full answer

Vishal S. - "Product Understanding - Push notifications are pop up notifications received on the device (phone, tablet etc.) sent by various Meta apps whenever a new post has been made or a new message is received Clarifying Questions - Is is specific to one device? Is it specific to one product? Is it specific to one region? Is it specific to one OS? Is this as a result of changes to algorithm/UI? Existing or a new feature? Assumptions - KPI calculation will only be for users who h"See full answer