big data

Question 1

define big data

Answer 1

too big or too complicated to be managed using normal techniques
no universally agreed definition

Question 2

what are the four V’s of big data

Answer 2

Volume; the size data, terabytes or even exabytes to process.
Velocity; the speed at which data flows, streaming milliseconds to record real time. sensor in a car.
Variety; the validity of the data, data inconsistency, latency
Veracity; the nature of the data (structured and unstructured formats), structured - databases, semi-structured - sml, unstructured - web search

Question 3

what is the problem with big data

Answer 3

storage. especially when the data is in different formats

Question 4

what is big data used for

Answer 4

data mining, data storage, data analysis, data sharing, data visualisation

Question 5

examples of big data

Answer 5

• The New York Stock Exchange generates about one
  terabyte of new trade data every day
• Facebook generates 4 new petabytes of data per
  day. Mainly in terms of photo and video uploads,
  message exchanges, comments etc.
• A single Jet engine can generate 10+ terabytes of
  data per flight
• Walmart processes 40 Petabytes of data, per day

Question 6

issues with big data

Answer 6

• Data is not knowledge
• It is very possible to be data rich but information
  poor (DRIP)
• Large data sets are often collected opportunistically,
  and not for the purpose of answering the question
  that you are now interested in
• Long term longitudinal data sets are often difficult
  to exploit
• Privacy, confidentiality and ethical considerations