DAT 250 EXAM 1 QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE 2026

DAT 250 EXAM 1 QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE 2026 What are the 3 types of big data? - Answers structured, unstructured, semi-structured What percent of data is structured? - Answers 5-10% What percent of data is unstructured? - Answers 80% What percent of data is semi-structured? - Answers 5-10% What type of data is email? - Answers unstructured What is structured data? - Answers Data that can be processed in a fixed format. Highly organized information that can be readily available An excel spreadsheet would be which type of data? - Answers Structured, due to organized rows and columns What are the 7 steps of the Data Science Lifestyle? - Answers Business Understanding, Data Mining, Data Cleaning, Data Exploration, Feature Engineering, Predictive Modeling, Data Visualization What is Business Understanding? - Answers Asking relevant questions and defining objectives for the problem that needs to be solved. What is Data Mining? - Answers "mining the data" -gathering and scoping the data necessary for the project What is Data Cleaning? - Answers "cleaning the data" -fixing the inconsistencies in the data and handling missing values What is Data Exploration? - Answers "exploring the data" -forming a hypothesis about your defined problem by visually analyzing the data What is Feature Engineering? - Answers Selecting important features & constructing more meaningful ones using the raw data you have. What is Predictive Modeling? - Answers -"using models to make predictions" -train machine learning models, evaluate their performance and use them to make predictions. What is Data Visualization? - Answers "visualizing the data" -communicate the findings with key shareholders using plots and interactive visualizations. What is data science? - Answers The practice of mining large data sets of raw data to identify patterns and get insight from them. -raw data is both structured and unstructured What is AI? - Answers Getting a computer to mimic human behavior in some way. What is machine learning? - Answers subset of AI -giving the computer a brain to learn from data -helps computers figure things out from data and deliver AI applications What is one of the most common tools data scientists use? - Answers open source notebooks- web applications for writing & running code and visualizing data all in one place ex: Jupyter, RStudio, & Zeppelin Who oversees data science process? - Answers Business managers, IT managers, and Data Science managers What is the contribution of the business manager? - Answers develop the problem and develop a strategy of analysis What is the contribution of the IT manager? - Answers may help build and update IT environments for data science teams -monitor operations and resource usage What is the contribution of the data science manager? - Answers oversees data science team team builders who balance development with project planning and monitoring Who is the most important role in the data science process? - Answers The data scientist. What is secondary use? - Answers Information collected for one purpose used for another How is Google's Personalized Search a secondary source? - Answers The information collected from Google about your search queries and Web pages can be used by companies/retailers for direct marketing. What is collaborative filtering? - Answers Analyzing information about preferences of large numbers of people to predict what one person may prefer. What are the explicit and implicit methods of collaborative filtering? - Answers Explicit filtering- asking people to rank preferences, ex: asking to give stars to a movie Implicit filtering- keeping track of purchases done by consumers, not asking directly What is opt-in? - Answers -Consumer must EXPLICITLY give permission before the organization can share info -need explicit consent -preferred by privacy advocates What is opt-out? - Answers -Organization can share information until the consumer explicitly forbids it -marks consent by default unless user rejects it -much more common than opt-in Why do many businesses and marketing organizations prefer opt-out? - Answers There are lower costs to do opt-out, and it is easier to advertise when they automatically assume consent from the user instead of directly asking. What is microtargeting? - Answers -special way that political campaigns figure out which people are the most likely to vote for their candidate. -they look at voter registration, voter frequency, consumer data and information available from GIS(geographic information system) -with this info, they will send specific messages via email, letters, and texts to the people they think are more likely to support a certain candidate. What is censorship? - Answers Attempt to suppress or regulate public access to material considered harmful or offensive How was censorship traditionally exercised? - Answers By government and religious institutions. How did the printing press affect censorship? - Answers It broke the monopoly governments and religious institutions had on distributing material to wide audiences. Now private individuals could broadcast their ideas to others on a wide scale. What are the 3 forms of direct censorship? - Answers Government monopolization, Prepublication Review, and Licensing and Registration What is government monopolization? - Answers When oppressive gov'ts can sensor info When governments control all media outlets(ex: former Soviet Union) What is prepublication review? - Answers All information is reviewed before being distributed publicaly. What is licensing and registration? - Answers Used to control media, need a license in order to broadcast. What is Self Censorship? - Answers -most common form of censorship -group decides for itself not to publish information What are some motives for self censorship? - Answers -avoiding punishment -staying on good terms with government officials ex: not showing certain things in a movie to not upset people, or having an age rating to warn viewers what age demographic the movie is for What are some challenges posed by the internet regarding censorship? - Answers -internet supports many-to-many communications - hard for the govt to stop someone from sharing their ideas on the internet -dynamic connections -always new devices every year -huge number of Web sites - there are so many websites that human censors can not keep track of them all