100+ Varde Paralkar & Associates Interview Questions and Answers

Transformations in Databricks involve manipulating data using functions like map, filter, reduce, etc.

• Transformations are operations that are applied to RDDs in Databricks

• Common transformations include map, filter, reduce, flatMap, etc.

• Transformations are lazy evaluated and create a new RDD

• Example: map transformation to convert each element in an RDD to uppercase

I created a KPI to measure customer retention rate.

• Developed formula to calculate percentage of customers retained over a specific period

• Monitored customer churn rate to track effectiveness of retention strategies

• Analyzed customer feedback and behavior to identify factors influencing retention

• Implemented initiatives to improve customer retention based on data insights

K-fold CV is a technique used to evaluate the performance of a machine learning model by splitting the data into k subsets.

• Data is divided into k subsets, with one subset used as the validation set and the rest as training sets.

• The process is repeated k times, with each subset used once as the validation data.

• The average of the k validation results is used as the final performance metric.

• Helps in reducing bias and variance in model evaluation.

• Example: 5-fold CV involves split...read more

Spark is a distributed computing framework for processing big data.

• Spark is built around the concept of Resilient Distributed Datasets (RDDs)

• It supports various programming languages like Scala, Java, Python, and R

• Spark provides high-level APIs like DataFrames and Datasets for structured data processing

• It includes libraries for SQL, streaming, machine learning, and graph processing

• Spark can run on various cluster managers like YARN, Mesos, and Kubernetes