What is Hadoop primarily used for in Big Data technologies?
- Data Storage and Processing
- Data Visualization
- Machine Learning
- Real-time Analytics
Hadoop is primarily used for distributed storage and processing of large volumes of data. It enables the distributed processing of data across clusters, making it suitable for tasks like batch processing and analytics.
What is the difference between 'forking' and 'cloning' a repository in Git?
- Forking creates a copy on the server, while cloning creates a copy on the local machine
- Forking is a Git command, while cloning is a GitHub action
- Forking is only possible for public repositories, while cloning is for private repositories
- Forking is used for individual development, while cloning is for collaborative projects
Forking creates a copy of a repository on the server under the user's account, while cloning creates a copy on the local machine. Forking is often used for contributing to open-source projects, while cloning is a general process of copying a repository.
What data structure is used to implement Depth First Search (DFS) on a graph?
- Array
- Linked List
- Queue
- Stack
Depth First Search (DFS) is typically implemented using a stack data structure. This is because DFS explores as far as possible along each branch before backtracking, which aligns well with the Last In, First Out (LIFO) nature of a stack.
Which SQL command is used to retrieve data from a database table?
- DELETE
- INSERT
- SELECT
- UPDATE
The SQL command used to retrieve data from a database table is SELECT. It allows you to query and fetch specific data based on specified conditions. UPDATE, DELETE, and INSERT are used for modifying or adding data.
What is the primary difference between an integer and a float data type in most programming languages?
- Integer and Float are the same data type.
- Integer can store larger values than Float.
- Integer is used for text data, while Float is used for numeric data.
- Integer stores whole numbers without decimals, while Float stores numbers with decimals.
The primary difference is that Integer stores whole numbers without decimals, while Float stores numbers with decimals. Integer and Float are both used for numeric data.
In advanced Excel, what method would you use to import and transform data from an external database?
- Advanced Filter
- Data Consolidation
- Data Validation
- Power Query
Power Query is the method used in advanced Excel to import and transform data from an external database. It provides a user-friendly interface to connect, import, and transform data seamlessly. Data Validation, Advanced Filter, and Data Consolidation are not specifically designed for importing and transforming external database data.
The process of estimating the parameters of a probability distribution based on observed data is known as _______.
- Bayesian Inference
- Hypothesis Testing
- Maximum Likelihood Estimation
- Regression Analysis
Maximum Likelihood Estimation (MLE) is the process of finding the values of parameters that maximize the likelihood of observed data. It's a fundamental concept in statistics for parameter estimation.
In time series analysis, the process of transforming a non-stationary series into a stationary series is known as _______.
- Aggregation
- Decomposition
- Differencing
- Smoothing
The blank is filled with "Differencing." Differencing is the process of transforming a non-stationary time series into a stationary one by computing the differences between consecutive observations. This helps remove trends and seasonality, making the series more amenable to modeling and analysis.
How does the principle of 'small multiples' aid in comparative data analysis?
- It emphasizes the use of small-sized charts to fit more data on a single page, improving visualization density.
- It focuses on reducing the overall size of the dataset to simplify analysis, making it more manageable.
- It involves breaking down a dataset into small, similar subsets and presenting them side by side for easy comparison, revealing patterns and trends.
- It suggests using minimalistic design elements to create a clean and uncluttered visual presentation of data.
The principle of 'small multiples' involves creating multiple, small charts or graphs, each representing a subset of the data. This aids in comparative analysis by allowing users to quickly identify patterns, trends, and variations across different subsets.
________ in ETL helps in reducing the load on the operational systems during data extraction.
- Cleansing
- Loading
- Staging
- Transformation
Staging in ETL involves temporarily storing extracted data before it is transformed and loaded into the target system. This helps reduce the load on operational systems during the data extraction phase.