BlackRock Interview Questions

How do you convert an expression in infix (or prefix) notation to postfix notation?

Find the least common ancestor of two nodes in an N-ary tree.

Derive the Ordinary Least Squares (OLS) estimator and discuss its bias.

How can you measure the extent to which the price of a security fluctuates?

What are covariance and variance? Define each and explain their differences.

How would you sort an array of numbers efficiently?

What are SQL correlated queries? Provide a definition and give an example.

Explain duration and its effect on bonds and bond valuations.

What is the square of 72?

Write Python code to access specific data from Excel and CSV files.

How can you join two database tables in SQL without using the JOIN keyword?

Implement a hashMap data structure. What are the differences between a hashMap and a treeMap?

1. What is the difference between shallow copy and deep copy in C++? 2. Implement a class using the singleton pattern in Java. 3. Find the first common ancestor of two nodes in a binary search tree (BST).

What are duration and convexity for bonds? Explain their definitions and how they are used in bond pricing and risk management.