Data and Analysis Flashcards

A student wants to visualize the distribution of quiz scores for a class of 30 students. Which visualization is MOST appropriate?

Answer: Histogram

A histogram groups continuous data into bins and displays frequency, making it ideal for showing the distribution of scores.

Which of the following BEST describes the purpose of data cleaning?

Answer: Removing duplicate or incorrect entries to improve data quality

Data cleaning involves identifying and correcting or removing inaccurate, incomplete, or duplicate records to improve dataset quality.

A scatter plot shows points trending upward from left to right. What does this indicate?

Answer: A positive correlation between the two variables

An upward trend from left to right in a scatter plot indicates a positive correlation — as one variable increases, the other tends to increase as well.

Which of the following is an example of structured data?

Answer: Rows and columns in a relational database table

Structured data is organized into a defined schema with rows and columns, such as a relational database or spreadsheet.

A program processes a list of names and counts how many times each name appears. What computational task is being performed?

Answer: Aggregation

Aggregation summarizes or groups data — counting occurrences of each name is a classic aggregation operation.

Which of the following statements about digital data representation is TRUE?

Answer: All digital data is ultimately represented as sequences of 0s and 1s

All digital data — whether text, images, audio, or video — is ultimately stored and processed as binary sequences of 0s and 1s.

A dataset of student GPAs has a mean of 3.2 and a median of 3.5. What does this suggest about the distribution?

Answer: There are likely low outliers pulling the mean down

When the mean is lower than the median, low-value outliers are pulling the mean down, creating a left-skewed (negatively skewed) distribution.