Data collection and data sources. Price statistics training Tbilisi, Georgia Randi Johannessen

Transcription

1 Data collection and data sources Price statistics training Tbilisi, Georgia Randi Johannessen

2 Price collection timing Prices for goods enter the HICP for the month prices are observed E.g. If on 20 May I buy a book to read in the plane when I fly to Tbilisi on 12 June, the price relates to the May CPI Prices for services shall be entered in the HICP when the service can commence E.g. If on 20 May I book a ticket to fly to Tbilisi on 12 June, the price relates to June CPI

3 Price collection frequency Price collection should take place during a period of at least one working week Near the middle of the calendar month For product with volatile prices, price collection shall take place over a longer period Energy, fruit and vegetables A temporary missing price should be imputed A permanent missing price should be replaced

4 Prices concept Purchase prices paid by households to purchase individual products in monetary transactions The price actually paid by the purchaser for products, including any taxes less subsidies on the products, after deduction of discounts from standard prices or charges, excluding interest or services charges added under credit arrangements and any extra charges incurred as a result of failing to pay within the period specified at the time of purchase

5 Price collection methods Locally: price collectors visiting a sample of retail outlets Centrally: price collection by staff in head office or regional offices Useful for products and services that are difficult to observe directly such as tariffs, public services Internet sites, catalogues, price lists, s, telephone, postal and electronic questionnaires, fax, letters, scanner data Choose the best practice due to local circumstances Structure of retailing, characteristics of outlets, geographical location, the range of goods and services available to purchase, the availability of alternative sources

6 Data collection in the field: the use of price collectors Corinne Becker Vermeulen Swiss Federal Statistical office 6

7 Objectives To show how such a system may work the necessary measures and importance of quality assurance the advantages and disadvantages/limits of using price collectors in the field 7

8 Essential elements for a qualitative price collection in the field Prices collected directly in outlets by professional price collectors (outsourced or not) Stable work distribution (for relationship and know how) Precise and well defined rules (handbook) Application of the rules must be uniform (training) Coordination among the different price collection areas On-site quality control 8

9 Price collection in the field usually for decentralised price collection Decentralised price collection Product groups / retailers with different prices throughout the country Centralised price collection Product groups / retailers with identical prices throughout the country Product groups demanding highly specialized staff 9

10 How does it work? (Swiss example) 10

11 How does it work? (Swiss example) At the end of each month: Prices to be (re)collected sent to the private company headquarter, with feedbacks from the last period / instructions Private company assigns item prices / outlets / feedbacks/instructions to price collectors Price collectors download their item prices from the private company Website Prices are imported on tablet for price collection 11

12 How does it work? (Swiss example) Price collection in the field Price collectors transmit prices continuously to the private company The private company does some quality control and sends prices to the statistical office (5x/month in the Swiss case) In-house staff continuously carries out quality controls 12

13 Quality assurance (QA) Quality assurance is the key to a high quality CPI QA must happen carefully on every level of the process: During price collection in the stores At the private company before and after price collection At the central office before and after price collection 13

14 QA in the stores by price collectors Price collectors are asked to control each price themselves Tablet software: Compares quantities and prices Warns price collectors in case of important changes (e.g. strong price evolution, unlikely quantity of an item etc.) Forces price collectors to add explanations in cases of relevant price/quantity changes Controls completeness of price reports 14

15 QA by the private company Checks data delivered by the statistical office before price collection Helps price collectors in the case of questions / problems to find new outlets, etc. Coordinates (uniformity of) communication between the statistical office / private company/ price collectors 15

16 QA by the private company Does QA on the collected price data itself, e.g. Correct prices / COICOP position / quantities Makes sure all the prices are collected Takes care of human resources (incl. short term absences etc.) Is responsible for training courses From time to time: Accompanies price collectors in stores 16

17 QA by the statistical office Extensive data checks by telephone, or internet (e.g. correct prices / COICOP-positions / quantities) Direct communication with price collectors over software application Price collectors must revisit the outlet in case of severe errors Spot checks in outlets right after the price collection (also by telephone or ) Accompany price collectors to a price collection Supports the private company in finding and recruiting appropriate outlets 17

18 QA by the statistical office Detailed monthly reporting on problems, difficulties or other particular points what to pay particular attention for next month special instructions etc. Together with the private company: Training courses every 6 months for the price collectors 18

19 QA by the statistical office Price collection handbook: Detailed rules and guidelines for price collection CPI basket Additional helpful information (e.g. wine list, cheese list ) Deadlines Data transfer Training courses 19

20 Advantages Uniform application of the rules and guidelines by experts (e.g. item selection and replacement, treatment of missing or seasonal items, etc.) uniform training courses compared to questionnaires: outlet staff not familiar with collection rules, does not have time, risk of poor data quality Deadlines and quality of price data are guaranteed by the private company Reduced burden of workload for the retail companies 20

21 Advantages The statistical office can focus on quality assurance, supervision and centralised price collection A new call for tender is issued every 5 years: pressure on the private market to deliver high quality results (at lower cost) Further tasks could be assigned to the private company: quality controls data codification Flexibility in case of changes in the survey 21

22 Limits / disadvantages Costly Some product groups are better suited for centralised price collection: Highly specialized price collections (eg. PCs, rents for dwellings, drugs etc.) Product groups / retailers with identical prices throughout the country Prices available on the internet 22

23 Conclusions Many advantages such as uniformity, coordination, flexibility and professionalism In Switzerland it was a major step up compared to the former system Quality assurance is very important at various level Improved quality comes at the price of higher expenses 23

24 Questions / Discussions How do you collect decentralised prices in your country and why? 24