The Data Science Lifecycle is a one-way street. Once you finish a step, you can't get back to it. True False.
What is mainly included in the Exploratory Data Analysis phase? Visualisation of the initial data Visualisation of the results Regression Diagnostics All of the above.
Which is not a goal of EDA? Investigating the Data Discovering patterns Visualising the data Spotting outliers & anomalies.
Which plot gives us information about the correlation between 2 variables? Histogram Scatter Plot Violin Plot Heatmap.
Histograms and KDEs can represent probability distributions. However, the first is used for categorical variables and the second is used for numerical variables. True False.
Feature Extraction involves talking to experts in the field and determining features that might be useful for us to solve our problem. True False.
Mostly, the challenge we can face with the features is: Feature Extraction Feature Engineering Curse of Dimensionality Data Leakage.
SVD is a technique that helps in reducing the dimensionality of the data and in the decorrelation of related features. True False.
A Database composed of tables connected to each other is a: Hierarchical Database Relational Database Non-Relational Database.
Tweets and blog posts are adequately stored in Relational Databases. True False.
Which plot is best suited to represent the daily number of cases of COVID-19? Histogram Line Chart Pie Chart All of the above.
When filling rows having null values, what's the best aggregate we can go for: Median Mean Count All of the above.
The goal of standardization is to make the variable range between 0 and 1. True False.
Which of the following is NOT considered data manipulation? Subsetting Cross Tabbing Visualisation None of the above.
Grouping the data by a variable for the rows, a variable for the columns, and then aggregating is called cross-tabbing. True False.
We can represent a __________ as a tree-like structure. Relational Database Non-Relational Database Hierarchical Database Data Warehouse.
The ELT approach used in Data Warehouses is better for security purposes. True False.
When we take data from a humidity sensor every 15 minutes, we are dealing with: Tabular Data Time Series Data Image Data Text Data.
When we put a CCTV camera outside of our house to avoid burglaries, we are dealing with: Image Data Time Series Data Video Data.
A DataBase Management System (DBMS) is a tool to store our data. True False.
When comparing machine learning algorithms and models, which one is the outcome or result of the other? Algorithms are the outcome of models. Models are the outcome of algorithms Algorithms and m(dels are synonymous Neither algorithms nor models are outcomes of each other.
Which type of plot is commonly used in EDA to visualize the distribution of a single continuous variable? Scatter plot. Bar chart Histogram Pie chart.
What is a common method for handling categorical variables in data wrangling? Deleting all categorical variables from the dataset Encoding categorical variables as numerical values. Ignoring categorical variables during analysis. Using them directly in machine learning models.
Which of the following is NOT a common data wrangling task? Data cleaning Data visualization Data transformation Handling missing data.
What does a positive correlation coeficient between two variables indicate? The variables are not related As one variable increases, the other tends to increase as well As one variable increases, the other tends to decrease The correlation coefficient cannot be positive.
What is a cross-tabulation (cross-tab or contingency table)? A data visualization technique A table that displays the frequency distribution of two or more categorical variables A statistical test for correlation A table of summary statistics.
In feature extraction, what is dimensionality reduction? Increasing the number of features in a dataset Reducing the number of features while preserving relevant information Measuring the curse of dimensionality Selecting the best features for a machine learning mode.
How does the curse of dimensionality affect machine learning models? It improves model performance by providing more data it leads to overfitting and increased computational complexity as the number of features increases. It has no impact on machine learning models It decreases the need for feature selection.
What is web scraping? A technique for securing websites from cyberattacks. A method of automating web browsing The process of extracting data from websites A method of designing web pages.
Which of the following is an example of crowdsourcing? A single individual analyzing data A group of experts collaborating on a research project An online platform where users contribute restaurant reviews A proprietary software developed by a company.
Which of the following is an example of time series data? A list of customer names and addresses Daily stock prices over a year A collection of product reviews Temperature measurements at different locations.
Which of the following is an example of unstructured data? A customer database with names and addresses A collection of tweets Sales transaction records A spreadsheet of product prices.
What is semi-structured data? Data that follows a strict schema Data that is neither structured nor unstructured Data that is loosely organized and may not conform to a rigid schema Data that is exclusively textual.
What is a Database Management System (DBMS)? A system for managing web content. A software application for creating and managing databases A system for managing hardware resources A programming language.
Which of the following is NOT a common type of DBMS? Relational DBMS NoSOL DBMS. Hierarchical DBMS. Excel Spreadsheet.
What is the primary purpose of data transformation in ETL and ELT processes? To load data into the data warehouse. To extract data from source systems. To change the format and structure of data to meet business requirements. To execute SOL queries on the data.
|
