40+ Machine Learning Intern Interview Questions and Answers for Freshers

There are various NER libraries available with different performances.

• Stanford NER - high accuracy but slow processing

• SpaCy - fast and accurate, supports multiple languages

• NLTK - widely used, but lower accuracy compared to others

• Flair - contextual embeddings for better accuracy

• BERT - pre-trained models for NER tasks

• CRF++ - Conditional Random Fields for NER

• GATE - rule-based and machine learning-based NER

• OpenNLP - Java-based NER library

Inference learning focuses on understanding the underlying relationships in data, while prediction learning focuses on making accurate predictions based on data.

• Inference learning involves understanding the causal relationships between variables in the data.

• Prediction learning focuses on building models that can accurately predict outcomes based on input data.

• Inference learning is more concerned with understanding the 'why' behind the data, while prediction learning is more f...read more

To build a regression model for a time series dataset, several steps need to be followed.

• Preprocess the data by checking for missing values, outliers, and transforming the data if necessary.

• Split the data into training and testing sets.

• Select a suitable regression algorithm such as linear regression, decision trees, or neural networks.

• Train the model on the training set and evaluate its performance on the testing set.

• Tune the hyperparameters of the model to improve its perfor...read more

Some optimizers and loss functions used in machine learning

• Optimizers: Adam, SGD, RMSprop

• Loss functions: Mean Squared Error (MSE), Cross Entropy, Hinge Loss

NER process identifies and extracts named entities from text data.

• NER stands for Named Entity Recognition.

• It involves identifying and classifying entities such as people, organizations, locations, and dates.

• NER can be performed using rule-based systems or machine learning algorithms.

• Examples of NER applications include information extraction, sentiment analysis, and chatbots.

• Popular NER tools include spaCy, NLTK, and Stanford NER.

Supervised learning uses labeled data to train the model, while unsupervised learning uses unlabeled data.

• Supervised learning requires a target variable for training, while unsupervised learning does not.

• In supervised learning, the model learns from labeled examples to make predictions on new data, while unsupervised learning finds patterns and relationships in data.

• Examples of supervised learning include classification and regression tasks, while unsupervised learning includ...read more

BOW and Count Vectorizer are both techniques used for text representation in NLP.

• BOW stands for Bag of Words and represents text as a collection of words without considering the order.

• Count Vectorizer is a technique that counts the frequency of each word in a document and represents it as a vector.

• BOW is a simpler technique and is used for tasks like sentiment analysis, while Count Vectorizer is used for more complex tasks like topic modeling.

• Both techniques are used in NLP f...read more

Inferential statistics infers properties of a population from a sample, while descriptive statistics describes the sample itself.

• Descriptive statistics summarizes and organizes data, while inferential statistics makes predictions and inferences about a larger population based on a sample.

• Descriptive statistics includes measures of central tendency (mean, median, mode) and measures of variability (range, standard deviation), while inferential statistics includes hypothesis tes...read more

Techniques to handle missing values in time series data.

• Imputation using mean, median or mode of the previous or next values.

• Interpolation using linear or spline methods.

• Extrapolation using regression models.

• Dropping missing values if they are insignificant in number.

• Using deep learning models like LSTM to predict missing values.

Elbow curve helps in determining the optimal number of clusters in K-means clustering.

• Elbow curve is a plot of the number of clusters against the within-cluster sum of squares.

• The point where the curve shows a sharp decrease and starts to flatten out is considered as the optimal number of clusters.

• It helps in finding the right balance between overfitting and underfitting in clustering.

• For example, if the elbow curve shows a clear bend at 3 clusters, then 3 clusters would be t...read more

Different types of learning in Machine learning include supervised learning, unsupervised learning, semi-supervised learning, reinforcement learning, and self-supervised learning.

• Supervised learning: Training data is labeled, algorithm learns to map input to output.

• Unsupervised learning: Training data is unlabeled, algorithm learns patterns and relationships in data.

• Semi-supervised learning: Combination of labeled and unlabeled data for training.

• Reinforcement learning: Agent ...read more

Support Vector Machine is a supervised learning algorithm used for classification and regression analysis.

• SVM finds the best hyperplane that separates the data into different classes.

• It maximizes the margin between the hyperplane and the closest data points.

• SVM can handle both linear and non-linear data using kernel functions.

• It is widely used in image classification, text classification, and bioinformatics.

• SVM can also be used for outlier detection and feature selection.

Supervised learning uses labeled data to train the model, while unsupervised learning uses unlabeled data.

• Supervised learning requires labeled data with input-output pairs for training, while unsupervised learning does not require labeled data.

• In supervised learning, the model learns to map input data to the correct output during training, whereas in unsupervised learning, the model finds patterns and relationships in the data without explicit guidance.

• Examples of supervised ...read more

I have worked on computer vision projects for 6 months during my coursework.

• Completed a computer vision project on object detection using YOLOv3 during a computer vision course

• Implemented facial recognition using OpenCV in a personal project

• Familiar with image processing techniques such as edge detection and image segmentation

Convolutional neural network (CNN) is a deep learning algorithm commonly used for image recognition and classification.

• CNN is designed to automatically and adaptively learn spatial hierarchies of features from input data.

• It uses convolutional layers to apply filters to input data, extracting features at different spatial locations.

• Pooling layers are used to reduce the spatial dimensions of the input data while retaining important information.

• CNNs are commonly used in computer...read more

Yes, I have worked on machine learning before.

• I have completed several online courses on machine learning.

• I have also worked on a project where I used machine learning algorithms to predict customer churn for a telecom company.

• I have experience with Python libraries such as scikit-learn and TensorFlow.

K means Clustering is a unsupervised machine learning algorithm used to group similar data points together.

• K means clustering is used to partition a dataset into K clusters based on their similarity.

• It is an iterative algorithm that starts with K random centroids and assigns each data point to the nearest centroid.

• The centroids are then recalculated based on the mean of the data points in each cluster and the process is repeated until convergence.

• It is widely used in image se...read more

Lists are mutable, tuples are immutable in Python.

• Lists are enclosed in square brackets [], tuples are enclosed in parentheses ().

• Elements in a list can be changed, added, or removed, while elements in a tuple cannot be changed.

• Lists are typically used for collections of similar items, tuples are used for fixed collections of items.

• Example: list_example = [1, 2, 3], tuple_example = (4, 5, 6)

SVM stands for Support Vector Machine, RBF stands for Radial Basis Function. RBF can have infinite dimensions.

• SVM is a supervised machine learning algorithm used for classification and regression tasks.

• RBF is a kernel function used in SVM to map data into a higher-dimensional space.

• RBF can have infinite dimensions, allowing it to capture complex relationships in the data.

Machine learning parameters include hyperparameters, model parameters, and training parameters that influence model performance.

• Hyperparameters: Settings that are not learned from the data, e.g., learning rate, batch size.

• Model Parameters: Weights and biases learned during training, e.g., coefficients in linear regression.

• Training Parameters: Settings related to the training process, e.g., number of epochs, optimization algorithm.

• Regularization Parameters: Techniques to preve...read more

Machine learning is a subset of artificial intelligence that enables machines to learn from data and improve their performance.

• Machine learning involves training algorithms to make predictions or decisions based on data

• It uses statistical techniques to identify patterns and relationships in data

• Examples include image recognition, speech recognition, and recommendation systems

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

• It has applications in various fields such as fi...read more

Deep learning is a subset of machine learning that uses neural networks to model and solve complex problems.

• Deep learning involves training neural networks with multiple layers to learn representations of data

• It is used for tasks such as image and speech recognition, natural language processing, and autonomous driving

• Popular deep learning frameworks include TensorFlow, PyTorch, and Keras

Linear Regression is a statistical method to model the relationship between a dependent variable and one or more independent variables.

• It is used to predict a continuous outcome variable based on one or more predictor variables.

• It assumes a linear relationship between the dependent and independent variables.

• It is commonly used in fields like finance, economics, and social sciences.

• It can be simple linear regression (one independent variable) or multiple linear regression (mor...read more

Supervised learning uses labeled data to make predictions, while unsupervised learning finds patterns in unlabeled data.

• Supervised learning requires labeled data to train the model and make predictions on new data.

• Examples of supervised learning include classification and regression.

• Unsupervised learning finds patterns in unlabeled data without any predefined output.

• Examples of unsupervised learning include clustering and dimensionality reduction.

NumPy is a powerful library for numerical computing in Python, providing support for large, multi-dimensional arrays and matrices.

• NumPy uses C and Fortran libraries in the background for numerical computations, making it faster than pure Python.

• It provides a powerful N-dimensional array object and functions for performing various mathematical operations on arrays.

• NumPy arrays are stored in contiguous blocks of memory, allowing efficient access and manipulation of data.

• Broadca...read more

To check for stationarity, we need to look for constant mean, variance, and autocovariance over time.

• Check for constant mean by plotting rolling statistics and performing Dickey-Fuller test.

• Check for constant variance by plotting the moving average of the squared series and performing statistical tests.

• Check for constant autocovariance by plotting autocorrelation function (ACF) and partial autocorrelation function (PACF).

• If the mean, variance, and autocovariance are constant ...read more

A confusion matrix is a table used to evaluate the performance of a classification model.

• It shows the number of true positives, false positives, true negatives, and false negatives.

• It helps in calculating various evaluation metrics like accuracy, precision, recall, and F1 score.

• It is useful in identifying the strengths and weaknesses of a model and improving its performance.

• Example: A confusion matrix for a binary classification problem would look like this: Actual Positive A...read more