DSS4M Exam2 2019

Pagina 1

EXAM: Data Science and Security for Mobility Year: 2019/20, Semester: 1, Exam Paper: 2 (13/2/2020) Student ID: Name: Answer the questions in the space provided. If you run out of room, you can use the spare pages at the end, (but remember to clearly mark which question you are answering). 1. What two conditions typically differentiate “big data” from “small data”? 2. Complete the sentence: “A computer program is said to learn from experience E with respect to a task T and performance measure P if ...” 3. List three or more different types of analysis that a data scientist might perform on data: 4. Consider a real-valued attribute height, a categorical variable eye-colour, and an ordinal variable education-level. For which of these variables is the greater-than inequality ”>” defined, and for which is it not defined? 1 5. If the attribute paymentMethod takes values ( creditcard, PayPal, storecredit ), how can we make use of this attribute to train a classifier that can only take numeric values as input? Explain. 6. What type of a variables are day-of-week and hour-of-day? Explain. 7. Customers of a hotel chain are asked to rate their experience staying in a particular hotel. If the possible response values are {terrible, poor, satisfactory, good, great, exceptional }, what type of variable would experience be? 8. In order to train a fraud detection system, Sarah collects 100,000 credit-card transactions. For each transaction she has 30 numeric attributes and also 4 categorical attributes. The categorical attributes can each take on 5 possible values. Approximately how much space (in MB) will be required to store the dataset? (Assume that the classifier only takes numeric features as input, each numeric/binary value is stored as a single Byte and that 1MB = 1,000,000B.) 9.…