This is a summary of the 8 Lectures given during this course. These lectures were provided by Vera Toepel & Bella Struminskaya. The summary consists of 21 pages in which the most important points are discussed. Furthermore, the important illustrations are also incorporated in it.
Three characteristics:
- Volume
- Velocity
- Variability
Administrative data: Provided by persons or organizations for regulatory or other
government activities
Transaction data: Generated as an automatic byproduct of transaction and activities (e.g.,
credit card data, traffic flow data)
Social media data: Created by people with the express purpose of sharing with (Some)
others
Sensor data: Generated by apps on for example smarthphones (GPS, accerometers,
biomarkers)
Limitations of big data
Couper (2013):
- Single variable, few covariates
- Bias through self-selection and self-presentation
- Volatility or lack of stability
- Privacy issues
- Access issues
- Opportunity for mischief
- Bigger does not mean better
Single variable, Limited covariates:
- Surveys are much more than a single variable
- Limited demographic variables provided or imputed may be wrong
- Knowing changing fuel prices is not the same as knowing what people do in response
to such changing prices
,Bias:
- Two sources of bias:
Selection bias:
- Not everyone uses social media
- Need to distinguish between producers and users of users of social media
- Not everyone uses loyalty cards or credits cards, or makes purchases online
Measurement bias:
- Impression management is a key element of social media
- The average Facebook user has MANY “friends”
Technological speed (Lack of stability):
Social media may be good for measuring short term trends, but surveys may be better for
longer-run measurement
Access Issues:
- Social media and transaction data are usually propriety
- A key strength of surveys is public access to data, permitting Replication and
reanalysis
Oppurtinity for mischief:
Example of justin Bieber fans. A part of them is fake but also counted as fans.
Bigger does not mean better
Example election polls USA.
Research process
, Introduction into survey methodology
- Developing and conducting a survey is an iterative process. Use the feedback given
by instructors and peers
Survey research:
- A method for gathering information about a specified group of people (Population)
by asking them questions
- For fact finding and theory testing
- Questions as well as answers are highly structured
- Ask yourself: Is a survey the best instrument to answer my research question?
When is a survey an appropriate tool?
- It is about populations: What unit of analysis? (Only when the unit is ‘individual’)
- How much do members of a population know? (Not too difficult questions)
- How much are respondents willing to reveal (Not to sensitive)
- It is about non-observable behavior
- It is only reliable when respondent is aware of behavior
- A survey is an unreliable tool to discover attitudes and behavior of the distant past
GIGO
- In order to prevent errors, scientists use a methodological framework
- In order to reduce the negative consequences of unavoidable errors that enter during
the research process, scientists use statistical tools
- Remember: you can rarely put right by statistics what you have messed up by design
- GIGO: Garbage In Garbage Out
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller marcokeijser. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.43. You're not tied to anything after your purchase.
