10+ TCS Interview Questions and Answers

Developed a machine learning model to predict customer churn for a telecom company.

• Used supervised learning techniques such as logistic regression and random forests

• Preprocessed data by handling missing values and encoding categorical variables

• Evaluated model performance using metrics like accuracy, precision, and recall

Common metrics for linear and logistic regression models are R-squared and confusion matrix respectively.

• For linear regression model, common metric is R-squared which measures the proportion of the variance in the dependent variable that is predictable from the independent variables.

• For logistic regression model, common metric is confusion matrix which includes metrics like accuracy, precision, recall, and F1 score to evaluate the performance of the model.

• Accuracy is the prop...read more

Random forest is an ensemble learning method that uses multiple decision trees to make predictions.

• Random forest is a collection of decision trees that are trained on different subsets of the data.

• Decision tree is a single tree-like structure that makes decisions based on features of the data.

• Random forest reduces overfitting by averaging the predictions of multiple trees.

• Decision tree can be prone to overfitting if not pruned properly.

• Random forest is more robust and accurat...read more

Insurance provides financial protection and peace of mind to common people in case of unexpected events.

• Insurance helps common people by providing financial protection against unexpected events such as accidents, illnesses, and natural disasters.

• It also provides peace of mind by reducing the financial burden and stress that comes with such events.

• Insurance can also help common people plan for their future by providing retirement and investment options.

• For example, health insu...read more

Ensemble technique combines multiple models to improve prediction accuracy.

• Ensemble methods include bagging, boosting, and stacking

• Random Forest is an example of ensemble technique using bagging

• Gradient Boosting Machine (GBM) is an example of ensemble technique using boosting

Linear regression is used for continuous variables while logistic regression is used for binary classification.

• Linear regression predicts continuous values while logistic regression predicts probabilities.

• Linear regression uses a linear equation to model the relationship between the independent and dependent variables.

• Logistic regression uses the logistic function to model the probability of a binary outcome.

• Linear regression is used for tasks like predicting house prices bas...read more

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

• Linear regression aims to find the best-fitting straight line that describes the relationship between variables.

• It is commonly used for prediction and forecasting in various fields such as finance, economics, and social sciences.

• The equation for linear regression is typically represented as y = mx + b, where y is the dependent variable, x...read more

Recall is the ratio of correctly predicted positive observations to the all observations in actual class. F1 is the harmonic mean of precision and recall.

• Recall is calculated as TP / (TP + FN)

• F1 score is calculated as 2 * (precision * recall) / (precision + recall)

• Recall is important in scenarios where false negatives are costly, like in medical diagnosis

I can achieve the target by setting clear goals, creating a plan, and consistently tracking progress.

• Set specific and measurable goals

• Create a detailed plan with actionable steps

• Track progress regularly and make adjustments as needed

• Stay motivated and focused on the end result

• Collaborate with team members and seek feedback

• Continuously learn and improve skills

I create client relations by building trust, providing excellent service, and maintaining open communication.

• Listen actively to clients' needs and concerns

• Respond promptly to inquiries and requests

• Provide personalized solutions and recommendations

• Follow up regularly to ensure satisfaction

• Offer value-added services and resources

• Maintain a positive and professional attitude

• Be transparent and honest in all interactions

• Show appreciation and gratitude for their business

Precision is the ratio of correctly predicted positive observations to the total predicted positive observations.

• Precision = True Positives / (True Positives + False Positives)

• It is a measure of the accuracy of the positive predictions made by the model.

• A high precision indicates that the model is good at predicting positive cases without many false positives.

Endorsement is the act of giving approval or support to something or someone.

• Endorsement can be in the form of a written or spoken statement of approval.

• It can also be a signature on a document to show support or agreement.

• Endorsement is commonly used in politics, advertising, and social media.

• For example, a celebrity endorsing a product can increase its popularity and sales.

• In online systems, endorsement can be in the form of likes, shares, or positive reviews.

• Endorsement ca...read more

LVM (Logical Volume Manager) is a tool used to manage disk storage in Linux systems by creating logical volumes from physical volumes.

• LVM allows for dynamic resizing of logical volumes without the need to unmount the filesystem.

• It provides features like striping, mirroring, and snapshotting for better data management.

• Commands like pvcreate, vgcreate, lvcreate are used to create physical volumes, volume groups, and logical volumes respectively.

VLOOKUP is a function in Excel used to search for a value in a table and return a corresponding value from another column.

• VLOOKUP stands for vertical lookup.

• It is commonly used to find data in large datasets or tables.

• The function requires four arguments: lookup value, table array, column index number, and range lookup.

• The lookup value is the value you want to search for.

• The table array is the range of cells that contains the data.

• The column index number is the column from wh...read more

Slicing in Python allows you to extract a subset of elements from a list.

• Slicing is done using square brackets and the start:stop:step notation.

• The start index is inclusive, while the stop index is exclusive.

• You can omit any of the three parameters, defaulting to 0 for start, length of list for stop, and 1 for step.

• Negative indices can be used to slice from the end of the list.

• Example: list = [1, 2, 3, 4, 5], list[1:4] will return [2, 3, 4].