Landmark Group Data Scientist Interview Questions and Answers

Q1. Bias and variance with respect to model
Ans. 
Bias and variance are two types of errors that can occur in a model.
• Bias refers to the error introduced by approximating a real-world problem, leading to underfitting.

• Variance refers to the error introduced by modeling the noise in the training data, leading to overfitting.

• Balancing bias and variance is crucial for creating a model that generalizes well to unseen data.
Answered by AI
Add your answer
Q2. Hypotheses test
Add your answer

Q1. How to reduce model inference latency
Ans. 
To reduce model inference latency, optimize model architecture, use efficient algorithms, batch processing, and deploy on high-performance hardware.
• Optimize model architecture by reducing complexity and removing unnecessary layers

• Use efficient algorithms like XGBoost or LightGBM for faster predictions

• Implement batch processing to make predictions in bulk rather than one at a time

• Deploy the model on high-performance har
Answered by AI
Add your answer
Q2. Different sql joins and their difference
Ans. 
SQL joins are used to combine rows from two or more tables based on a related column between them.
• INNER JOIN: Returns rows when there is at least one match in both tables.

• LEFT JOIN: Returns all rows from the left table and the matched rows from the right table.

• RIGHT JOIN: Returns all rows from the right table and the matched rows from the left table.

• FULL JOIN: Returns rows when there is a match in one of the tables.

• SEL
Answered by AI
Add your answer

Q1. Intermediate level SQL questions using joins and case when
Add your answer
Q2. String manipulation advanced level question in python
Add your answer

A/B Testing, data structures

Q1. Past experience
Add your answer

3 Leet code mediums in 30 mins.

Q1. 5 ML questions in 10 mins
Add your answer
Q2. 5 Stats question in 10 mins
Add your answer
Q3. 3 LC mediums in 30 minutes
Ans. 
LC mediums refer to LeetCode mediums, which are medium difficulty coding problems on the LeetCode platform.
• LC mediums are coding problems with medium difficulty level on LeetCode platform.

• Solving 3 LC mediums in 30 minutes requires good problem-solving skills and efficient coding techniques.

• Examples of LC mediums include 'Longest Substring Without Repeating Characters' and 'Container With Most Water'.
Answered by AI
Add your answer

Q1. Why do you want to leave your current job?
Add your answer

SQL coding question. Medium level

Explain my project and then case study regarding launching new apps

Q1. Linear regression
Add your answer
Q2. Probability related questions
Add your answer
Q3. Sampling and AB testing
Add your answer

Q1. Backpropagation in neural network
Ans. 
Backpropagation is a method used to train neural networks by adjusting the weights based on the error in the output.
• Backpropagation involves calculating the gradient of the loss function with respect to the weights of the network.

• The gradient is then used to update the weights in the opposite direction to minimize the error.

• This process is repeated iteratively until the network converges to a solution.

• Backpropagation i...read more
Answered by AI
Add your answer
Q2. Clustering (k-means, DB scan)
Add your answer

1 question on array (sorting related), 1 question on string (hard problem)

Q1. Behavioral questions
Add your answer