You are designing a deep learning model for a multi-class classification task with 10 classes. Which activation function and loss function combination would be the most suitable for the output layer?
- Sigmoid activation function with Mean Squared Error (MSE) loss
- Softmax activation function with Cross-Entropy loss
- ReLU activation function with Mean Absolute Error (MAE) loss
- Tanh activation function with Huber loss
For multi-class classification with 10 classes, the most suitable activation function for the output layer is Softmax, and the most suitable loss function is Cross-Entropy. Softmax provides class probabilities, and Cross-Entropy measures the dissimilarity between the predicted probabilities and the true class labels. This combination is widely used in classification tasks.
What is the primary goal of Exploratory Data Analysis (EDA)?
- Predict future trends and insights
- Summarize and explore data
- Build machine learning models
- Develop data infrastructure
The primary goal of EDA is to summarize and explore data. It involves visualizing and understanding the dataset's main characteristics and relationships before diving into more advanced tasks, such as model building or predictions. EDA helps identify patterns and anomalies in the data.
What is the primary characteristic that differentiates Big Data from traditional datasets?
- Volume
- Velocity
- Variety
- Veracity
The primary characteristic that differentiates Big Data from traditional datasets is "Variety." Big Data often includes a wide range of data types, including structured, unstructured, and semi-structured data, making it more diverse than traditional datasets.
In the context of Data Science, the concept of "data-driven decision-making" primarily emphasizes on what?
- Making decisions based on intuition
- Using data to inform decisions
- Speeding up decision-making processes
- Ignoring data when making decisions
"Data-driven decision-making" underscores the significance of using data to inform decisions. It implies that decisions should be backed by data and analysis rather than relying solely on intuition. This approach enhances the quality and reliability of decision-making.
Which metric is especially useful when the classes in a dataset are imbalanced?
- Accuracy
- Precision
- Recall
- F1 Score
Recall is particularly useful when dealing with imbalanced datasets because it measures the ability of a model to identify all relevant instances of a class. In such scenarios, accuracy can be misleading, as the model may predict the majority class more frequently, resulting in a high accuracy but poor performance on the minority class. Recall, also known as true positive rate, focuses on capturing as many true positives as possible.
In time series forecasting, which method involves using past observations as inputs for predicting future values?
- Regression Analysis
- ARIMA (AutoRegressive Integrated Moving Average)
- Principal Component Analysis (PCA)
- k-Nearest Neighbors (k-NN)
ARIMA is a time series forecasting method that utilizes past observations to predict future values. It incorporates autoregressive and moving average components, making it suitable for analyzing time series data. The other options are not specifically designed for time series forecasting and do not rely on past observations in the same way.
In which type of learning does the model discover patterns or structures without any prior labeling of data?
- Supervised Learning
- Unsupervised Learning
- Semi-Supervised Learning
- Reinforcement Learning
Unsupervised Learning is the type where the model discovers patterns or structures without prior data labeling. Common tasks in this category include clustering and dimensionality reduction, helping find hidden insights in data without any guidance.
For time-series data, which variation of gradient boosting might be more appropriate?
- XGBoost
- AdaBoost
- LightGBM
- Random Forest
Time-series data often has specific characteristics, such as seasonality and trends. LightGBM is well-suited for such data as it can handle categorical features efficiently and is capable of capturing complex patterns, making it a strong choice for time-series forecasting.
An e-commerce platform wants to store the activities and interactions of users in real-time. The data is not structured, and the schema might evolve. Which database is apt for this scenario?
- Relational Database
- Document Database
- Event-Driven Database
- Time-Series Database
An event-driven database, such as Apache Kafka, is suitable for capturing and storing real-time activities and interactions, especially when the data is unstructured, and the schema might evolve over time.
A self-driving car system needs to detect pedestrians, traffic lights, and other vehicles in real-time. What computer vision technique would be most suitable for this?
- Object Detection
- Image Classification
- Semantic Segmentation
- Optical Character Recognition (OCR)
For real-time object detection in computer vision, the most suitable technique is "Object Detection." It allows the system to identify and locate specific objects, such as pedestrians, traffic lights, and vehicles, in a given frame or scene. Image classification, semantic segmentation, and OCR serve different purposes.