Question
Why is sampling a critical step in large-scale data
analysis?Solution
Explanation: Sampling is a critical step in data analysis, especially when dealing with large datasets. By selecting a smaller, representative subset of the population, analysts can perform computations faster and with fewer resources while retaining the integrity of the results. Effective sampling reduces data complexity and ensures that the sample mirrors the population's characteristics, enabling reliable statistical inferences. Techniques like simple random sampling or stratified sampling ensure diversity and minimize bias, maintaining the overall data quality for analysis. Option A: While sampling aids in efficient predictions, it does not involve using all available data. Sampling is about selecting a subset, not the entire dataset. Option C: Sampling does not eliminate the need for advanced techniques; it complements them by making analysis feasible for large datasets. Option D: Including all rare events is not guaranteed through sampling; specific strategies like oversampling are needed for rare-event analysis. Option E: Sampling reduces but does not eliminate bias. Proper technique selection minimizes it.
Which of the following is a type of phishing attack?
Which SQL statement is used to remove all rows from a table without logging individual row deletions?
Which type of relationship exists when a record in one table can relate to multiple records in another table, and vice versa?
Which of the following is a property of a relational database?
Which SQL command is used to retrieve data from a database?
Which of these ensures referential integrity?
Which normal form ensures that every determinant is a candidate key?
What is a table joined with itself called?
Which SQL isolation level allows phantom reads but prevents dirty reads and non-repeatable reads?
Which of the following best describes the control flow when a method in a subclass overrides a method in its superclass, and an object of the subclass i...