Cognitive Data Scientist Interview Questions and Answers

No, statistical models and Machine Learning are not the same.

• Statistical models are based on mathematical equations and assumptions, while Machine Learning uses algorithms to learn patterns from data.

• Statistical models require a priori knowledge of the data distribution, while Machine Learning can handle complex and unstructured data.

• Statistical models are often used for hypothesis testing and parameter estimation, while Machine Learning is used for prediction and classificat...read more

Yes, I am familiar with R.

• I have experience in data analysis and visualization using R.

• I have used R for statistical modeling and machine learning.

• I am comfortable with R packages such as ggplot2, dplyr, and tidyr.

Principal Component Analysis is a statistical technique used to reduce the dimensionality of a dataset while retaining important information.

• PCA identifies the underlying structure in the data by finding the directions of maximum variance.

• It transforms the data into a new coordinate system where the first axis has the highest variance, followed by the second, and so on.

• The transformed data can be used for visualization, clustering, or classification.

• PCA assumes that the data ...read more

Machine learning is a subset of artificial intelligence that involves training algorithms to make predictions or decisions based on data.

• Machine learning involves using algorithms to learn patterns in data

• It can be supervised, unsupervised, or semi-supervised

• Examples include image recognition, natural language processing, and recommendation systems

Cognitive refers to the mental processes and abilities related to perception, learning, memory, reasoning, and problem-solving.

• Cognitive refers to the mental processes and abilities of the brain.

• It involves perception, learning, memory, reasoning, and problem-solving.

• Cognitive science studies how these processes work and interact.

• Cognitive data science applies data analysis techniques to understand and improve cognitive processes.

• Examples include analyzing brain activity data...read more

Kernels are small matrices used in image processing and machine learning algorithms to perform operations on images or data.

• Kernels are used in convolutional neural networks (CNNs) to extract features from images.

• They are also used in image processing techniques like blurring, sharpening, and edge detection.

• Kernels can be represented as matrices of numbers that are applied to the input data to produce an output.

• In machine learning, kernels are used in support vector machines ...read more