_______ is a technique used to handle imbalanced datasets in predictive model training.
- K-Means Clustering
- Mean Imputation
- Principal Component Analysis
- SMOTE (Synthetic Minority Over-sampling Technique)
SMOTE (Synthetic Minority Over-sampling Technique) is a technique used to handle imbalanced datasets in predictive model training. It generates synthetic samples for the minority class to balance the dataset and improve the model's performance on minority class instances.
A data warehouse that is designed to focus on a specific business area or department is called a _______.
- Data Cluster
- Data Mart
- Data Silo
- Data Warehouse
A Data Mart is a subset of a data warehouse that is designed to focus on a specific business area or department. It contains a more specialized set of data that is relevant to a particular group of users.
During the transform phase of ETL, what is a key task performed on the data?
- Cleaning and restructuring
- Data extraction
- Data loading
- Indexing
In the transform phase of ETL (Extract, Transform, Load), a key task is cleaning and restructuring the data. This involves operations such as filtering, aggregating, and transforming the data to make it suitable for the target system or database.
The _______ method combines multiple weak models to create a stronger predictive model.
- Classification
- Clustering
- Ensemble
- Regression
The Ensemble method combines multiple weak models (such as decision trees) to create a more robust and accurate predictive model. This approach aims to reduce overfitting and improve generalization.
For a project requiring quick data exploration and visualization of Big Data, which tool would be most effective?
- Apache Spark
- Hadoop
- MongoDB
- Tableau
Tableau is a powerful data visualization tool that excels in quick data exploration and visualization. It allows users to create interactive and insightful visualizations from large datasets, making it an effective choice for projects requiring rapid exploration of Big Data.
In SQL, the _______ keyword is used to sort the result set in either ascending or descending order.
- GROUP BY
- HAVING
- JOIN
- ORDER BY
The ORDER BY keyword in SQL is used to sort the result set of a query in either ascending (ASC) or descending (DESC) order based on one or more columns.
What is the first step typically taken in the data cleaning process?
- Data collection
- Data visualization
- Handling missing data
- Remove duplicates
The first step in the data cleaning process is often to collect the data. Without proper data collection, it's challenging to identify and address issues related to duplicates, missing data, or other quality issues.
Which stage of the ETL process involves cleaning and transforming raw data into a suitable format?
- Evaluation
- Extraction
- Loading
- Transformation
The Transformation stage in the ETL process involves cleaning and transforming raw data into a suitable format. This ensures that the data is consistent, accurate, and ready for analysis.
In a complex dashboard, how is data normalization important for comparative analysis across different metrics?
- It ensures consistent units and scales across metrics.
- It increases the complexity of the dashboard.
- It only impacts visual aesthetics.
- It reduces the need for comparative analysis.
Data normalization is crucial in a complex dashboard to ensure that different metrics are on consistent units and scales. This allows for meaningful comparative analysis without the distortion caused by varying units or scales.
A _______ data structure is used for storing data elements that are processed in a last-in, first-out (LIFO) order.
- Linked List
- Queue
- Stack
- Tree
A stack is used for storing data elements in a last-in, first-out (LIFO) order. It means the element that is added last is the one that is removed first. Stacks are commonly used in programming for tasks like function calls and undo mechanisms.