online index - eugine kang

온라인 마켓 상품 댓글 정보를 이용한 온라인 물가지수

고려대학교지도교수 : 진서훈 교수님

석사졸업예정학생 : 강유진 [2013021403]

Content

1. Purpose, why is this research needed?

2. History, what has been done regarding this research?

3. Method, what methods were applied for this research?

4. Finding, what was revealed through this research?

5. Conclusion, what do we know after this research?

6. Reference, what previous research aided this research?

1. Purpose

1. Purpose

1. Purpose

Billion Prices Project exists in: USA, Argentina, Brazil, Chile, Columbia, and Venezuela

Billion Prices Project does not exist in South Korea

Solideo Systems attempted at creating a BPP for South Korea, but my research is to attempt at enhancing it with online reply data and index equation.

2. History

Solideo Systems are the first group to attemp creating a Billion Prices Project for South Korea

However, the results do not show consistency with Customer Price Index (CPI)

2. History

2. History

2. History

2. History

2. History

Very Different from Ideal

2. History

2. History, Problem with Data?

2. History, Problem with Data?

2. History, Problem with Data?

2. History, Problem with Data?

2. History, Problem with Data?

Prince Index requires consistent data collection of prices for given products.

However, Solideo Systems’ data is not collected consistently.

3. Method

This research attempts to use online reply data. However, the reply data is not collected.

Web scraping technique was used to collect online reply data.

3. Method, web scraping

3. Method, web scraping

3. Method, web scraping

3. Method

Jevons Index requires the price at time t and time t-1. The number of items with prices is denoted by n.

The Jevons Index does not require any weight for calculation.

3. Method

Solideo Systems adjusted the Jevons Index by multiplying weight, w, to the power.

Weight is where the item is located on the list of online market.

If the item is at the top of the list, the weight is higher. As the item goes down the list, the weight decreases as well.

3. Method

This research adjusts the weight given by Solideo System to something that reflects the popularity of the item.

Reply data is used as a pseudo variable measuring the amount item has been sold.

I believe this gives a better picture of customer spending habits.

3. Method

This research also applies the Tornqvist Index to the given data.

Tornqvist index requires a weight for calculation, but we adjusted the index by giving reply data as the weight.

4. Finding

4. Finding

4. Finding

4. Finding

4. Finding

우유 CPI세탁세제

CPI

종이기저귀

CPI

스낵과자

CPI

BPP -0.812 0.387 -0.228 0.692

Jevons (7 일 ) 0.045 -0.237 -0.175 0.657

Tornqvist (7 일 ) -0.569 -0.029 -0.598 0.759

Data cleaning, and adjusting the index equation yielded increased correlation for Snacks index, but did not improve other indexes.

5. Conclusion

• This research attempted at enhancing the BPP index for South Korea. The only attempt in creating the index was from Solideo Systems.

• However, exploratory analysis revealed the data collected did not show consistency when collecting.

• This results as a problem for calculating a reliable price index.

• Price Index requires a consistent collection of price data, but the given data does not provide.

5. Conclusion

• This research attempted at enhancing the BPP index for South Korea. The only attempt in creating the index was from Solideo Systems.

• However, exploratory analysis revealed the data collected did not show consistency when collecting.

• This results as a problem for calculating a reliable price index.

• Price Index requires a consistent collection of price data, but the given data does not provide.

5. Conclusion

• Reply data seemed to be a good data for indicating item popularity. Web scraping of online market sites were done to collect reply data.

• Jevons, and Tornqvist Index equations were adjusted to provide a better picture of customer spending habit.

• The results from data cleaning, data collection, and equation adjustment did not improve the correlation of all indexes.

• Consistent data collection of item prices is required to further advance the BPP for South Korea.

1. Cavallo, Alberto. "Online and official price indexes: Measuring Argentina's inflation." Journal of Monetary Economics 60.2 (2013): 152-165.

2. Cavallo, Alberto. "Scraped data and sticky prices." (2012).

3. Cavallo, Alberto, and M. I. T. Sloan. "The Billion Prices Project: Building Economic Indicators From Online Data." Meeting of the Group of Experts on Consumer Price Indices, United Nations Economic Commission for Europe, Geneva, May. Vol. 31. 2012.

4. Cavallo, Alberto, and Roberto Rigobon. The distribution of the Size of Price Changes. No. w16760. National Bureau of Economic Research, 2011.

5. Kohli, Ulrich. "An Implicit Törnqvist Index of Real GDP." Journal of Productivity Analysis 21.3 (2004): 337-353.

6. Reference