Validation Tables Quaranta and Dikhanov

ICP-Africa Regional WorkshopPretoria, South Africa

20 - 24 June 2011

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Introduction to Validation Tables

The Quanranta Tables (QTs)

The Dikhanov Tables (DTs)

Relation between QTs and DTs

Outlinevalidation tables

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• The Quaranta Tables

The main data analysis within inter-country and global validation is carried out by using two validation tables that are

• Screen the national average prices for possible errors by comparing the average prices for the same product in different countries

The purpose of the both tables is to

Introduction tovalidation tables

• The Dikhanov Tables

• Editing of price data for an itemThis analysis can lead to

• Editing of metadata for an item

• Possible errors are highlighted by special indices

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• Summary tables for each BH

The Quaranta Tables (QTs) consist of a set of tables

• BH PPPs and PLIsQTs can be used for the validation of

Quanranta Tablesvalidation tables

• Individual tables for each item

• EKS, EKS*, CPD, CPRD and W-CPDDifferent calculation options

• Recommended method by the TAG is weighted CPD

• Item XR-ratios and CUP-ratios

• However comparison of results for different calculation methods can be used to value given information on importance

• Table details

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OverviewQuaranta tables

QUARANTA TABLE DIAGNOSTICS - RiceData Selection Criteria

Basic Heading Code 99.11.01.11.1 Time Period Yearly

Run Date 4/13/2011

Averaging Method Arithmetic Mean Imputation CPD  Summary Information

No of Items included in the Analysis 6 out of 6

Average weight of Basic Heading in Total Expenditure 0.0  

No of Countries included in the Analysis 18 out of 18 Average Coefficient Variation 27.4  Base Country USA  

Country Level Details# Shares are multiplied by 10000.  

  Country XR PPP PLI(%) Weight # Items Var.Co.    Country 1 4.42 1.8150 41.080% 0.0 2;*0 7.2    Counrty 2 959.04 718.2770 74.896% 0.0 5;*0 8.2    Counrty 3 1018.35 2.7696 0.272% 0.0 2;*0 33.8  

Item Level Details99.11.01.1

1.1.01 Long grain rice, prepackedVar.Co.: 25.9 1-Kilograms

Country NC-PriceQuotati

ons Var.Co. XR-pr XR-ratioCUP-price

CUP-ratio Pref. UoM

Country 1 1.500 151 11.2 0.34 45.89 0.83 95.02 NACountry 2 - - - - - - - NACountry 3 766.381 10 3.0 72.93 9857.61 1.14 130.66 NA

Table details

BH table

Item table

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Table detailsQuaranta tables

QUARANTA TABLE DIAGNOSTICS

Basic Heading Code 99.11.01.11.1

Averaging Method Arithmetic Mean

Time Period Yearly

Imputation CPD

Run Date 4/13/2011

Data Selection Criteria

No of Items included in the Analysis 6 out of 6

No of Countries included in the Analysis 18 out of 18

Average weight of Basic Heading in Total Expenditure 0.0

Average Coefficient Variation 27.4

Summary Information

Base CountryCountry

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Table detailsQuaranta tables

# Basic Heading Code

Period Period during which the prices for the products covered by the Table were collected.

Run date Run date for the tablesAveraging Method Method used to calculate the averages

Imputation Method used to calculate the basic heading PPPs EKS, EKS*, CPD or CPDR.# Number of Items included in the analysis

WeightNational expenditure weights scaled to 100,000. That part of a country's GDP that is spent on the basic heading when both expenditures are expressed in national currency and valued at national price levels. For information only: not used in the calculations

# Number of Countries included in the analysis

Average Coefficient Variation

Overall variation coefficient i.e. the average product variation coefficient for the products priced for the basic heading. It is calculated as the unweighted arithmetic mean of the product variation coefficients at. It measures the average variation of the PPP-Ratios of all products priced for the basic heading.

Base CountryBase country for the calculations (currency selected as numéraire).

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BH tableQuaranta tables

BH Table

Country

Country 1

XR

4.42

PPP

1.8150

# Shares are multiplied by 10000.

PLI (%)

41.080%

Weight #

0.0

Items

2;*0

Var.Co.

7.2

Country 2 718.2770 74.896% 0.0 5;*0 8.2 959.04

Country 3 2.7696 0.272% 0.0 2;*0 33.8 1018.35

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BH table detailsCountry Names of countries covered by the Table.

XR Market exchange rates of the countries expressed as the number of units of national currency per unit of the numéraire currency (base country).

PPP

Purchasing power parities for the basic heading calculated and expressed as the number of units of national currency per unit of the selected numéraire currency. The prices used to calculate the PPPs are the average prices in national currencies that countries report for the products they priced for the basic heading - that is, the NC-Prices.

PLI Price Level Indices. The PPPs expressed as a percentage of the corresponding exchange rate.

WeightNational expenditure weights scaled to 100,000. That part of a country's GDP that is spent on the basic heading when both expenditures are expressed in national currency and valued at national price levels.

No. of ItemsNumber of products that are priced by each country for the basis heading and the number of products priced by each country that are important - that is, the number of products assigned an asterisk (*).

Var.Co.Country variation coefficient. The standard deviation of the country's CUP-Ratios for all products priced by the country for the basic heading expressed as a percentage of the arithmetic mean of the country's CUP-Ratios for all products priced by the country for the basic heading.

BH Table detailsQuaranta tables

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Item tableQuaranta tables

Item Table

Country NC-Price

Long grain rice, prepacked

Quotations Var.Co. XR-pr

Var.Co.:

XR-ratio

25.9

CUP-price

Country 1

Country 2

99.11.01.11.1.01 1-Kilograms

CUP-ratio

Pref. UoM

Country 3

1.500 151 11.2 0.34 45.89 0.83 095.02 NA

- - - - - - - NA

766.38 10 3.0 72.93 9857.6 1.14 130.66

NA

Geo Mean 0.74 0.87

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Item table detailsQuaranta tables

Item table detailsCode Code, name, and summary definition of the product covered in the subsequent product section.

Var.Co. Item variation coefficient. The standard deviation of the product's PPP-Ratios expressed as a percentage of the arithmetic mean of the product's PPP-Ratios.

Pref. UoM Unit of measurement Country Country nameNC-Price Average price in national currency (NC).

Quotations Number of price observations on which the average prices in national currency are based.

Var.Co.Price observation variation coefficient. The standard deviation of the price observations underlying the product's average price expressed as a percentage of the arithmetic mean of the price observations underlying the product's average price.

XR-Price The average prices in national currency in column [24] converted to the numéraire currency with the exchange rates.

XR-Ratio Standardized price ratios based on the exchange rate converted prices. The XR-Prices expressed as a percentage of their geometric mean.

CUP-Price The average prices in national currency converted to the numéraire currency with the PPPs.

CUP-Ratio Standardized price ratios based on the PPP converted prices. The PPP-Prices expressed as a percentage of their geometric mean.

Geo Mean Geometric mean of the exchange rate converted prices and CUP-Prices

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• Summary table for each BH

As the QTs, the Dikhanov Tables (DTs) consist of a set of tables

• Aggregated (above BH) and BH PPPs and PLIsDTs can be used for the validation of

Dikhanov Tablesvalidation tables

• Individual tables or rows for each item

• CPD, CPRD, CPD-WDifferent calculation options

• Item XR-Ratios and CPD(R) residuals

• Table details

• Aggregate/BH tables + full item statisticsDifferent lay-out options including color scheme

• Aggregate of BH tables + simple residual rows for item

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OverviewDikhanov tables

Table details

BH table

Item table

Dikhanov Temporal Analysis Country1 Country2 Country3 Yearly - 2005 Yearly - 2005 Yearly - 2005 PPP 2.934690064 658.1289976 4.040426119 STD 0.245237431 0.256006128 0.291549487 No.of Priced Items 420 513 572 ER (LCU/US$) 2.43 527.47 5.78 Rebased_XR 4.418181818 959.0363636 10.50909091 PLI 0.664230261 0.686239878 0.384469613   

Item Level Details Country1 Country2 Country3Item Code Item Name Yearly - 2005 Yearly - 2005 Yearly - 2005

99.11.01.11.1 Rice  

PPP 1.81507 718.297 4.84856 STD 0.05109 0.0726994 0.274263 PLI 0.410819 0.748978 0.461368 No.of Priced Items 2 5 6

99.11.01.11.1.01 Long grain rice, prepacked -0.05109 - 0.26746

Average Price 1.5 - 5.51 No.of Observations 151 - 10 Coefficient of Variation 11.2214 - 3 XR Ratio 70.4386 - 108.78

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Table details Dikhanov tables

Country 1 Country 2 Country 3

PPP 2.93 658.13 4.04

STD 0.25 0.26 0.29

No.of Priced Items 420 513 572

ER (LCU/US$) 2.43 527.47 5.78

DIKHANOV

Rebased_XR 4.42 959.04 10.51

PLI 0.66 0.69 0.38

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Table Details

PPP

Purchasing power parities for the basic heading or aggregate covered by the Table. They are expressed as the number of local currency units per unit of the selected numéraire currency. The prices used to calculate the PPPs are the average prices in local currencies that countries report for the products they priced for the basic heading or aggregate - that is the average prices.

STDStandard deviation of each country’s CPD or CPRD residuals for the basic heading or aggregate. It can be converted to a country variation coefficient by multiplying by 100.

# Number of products specified for the basic heading or aggregate.

ER (LCU/US$)

Market exchange rates of countries expressed as the number of local currency units per US dollar.

Rebased XR Exchange rates rebased to the numéraire currency. Number of local currency units per unit of numéraire currency.

PLI Price level indices. The PPPs expressed as a ratio of the corresponding rebased exchange rates in row.

Table details Dikhanov tables

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BH detailsDikhanov tables

Country 1 Country 2 Country 3

Item Code Yearly - 2005

Yearly - 2005

Yearly - 2005

Item Level Details

99.11.01.11.1 Rice

PPP

Item Name

1.82 718.30 4.85

0.05 0.07 0.27

0.41 0.75 0.46

STD

PLI

2 5 6No.of Priced Items

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BH detailsDikhanov tables

BH DetailsItem code Code of the basic heading or aggregate covered by the Table.Item name Name of the basic heading or aggregate covered by the Table.

Period Period during which the prices for the products covered by the Table were collected.

PPP

Purchasing power parities for the basic heading or aggregate covered by the Table. They are expressed as the number of local currency units per unit of the selected numéraire currency. The prices used to calculate the PPPs are the average prices in local currencies that countries report for the products they priced for the basic heading or aggregate - that is the average prices.

STDStandard deviation of each country’s CPD or CPRD residuals for the basic heading or aggregate. It can be converted to a country variation coefficient by multiplying by 100.

PLI Price level indices. The PPPs expressed as a ratio of the corresponding rebased exchange rates in row.

# Number of products specified for the basic heading or aggregate.

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Item detailsDikhanov tables

Item Code Yearly - 2005

Yearly - 2005

Yearly - 2005

Item Level Details

99.11.01.11.1.01Long grain

rice

Average Price

Item Name

1.50 -

151 -

11.22 -

No.of Observations

Coefficient of Variation

70.44 - 108.78XR Ratio

-0.05 - 0.27

5.51

STD

3.00

0.25

Count

13

Country 1

Country 2

Country 3

10

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Item detailsDikhanov tables

Item DetailsItem code Code of the basic heading or aggregate covered by the Table.Item name Name of the basic heading or aggregate covered by the Table.

Period Period during which the prices for the products covered by the Table were collected.

STDStandard deviation of the product’s CPD or CPRD residuals. It can be converted to a product variation coefficient by multiplying by 100. The mean of a product’s residuals is 1.

Count Number of countries pricing the product.

Residual CPD or CPRD residuals by product and country. CPD residuals in the Dikhanov table are equal to the logarithms of the CUP-Ratios in the Quaranta table.

Average PriceAverage price in local currency units.

# Number of price observations on which the average prices at [16] are based.

Coef. of Var. Price observation variation coefficient.

XR Ratio Price ratios based on exchange rate converted prices. The converted prices expressed as a percentage of their geometric mean.

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Both tables provides essentially the same information, but

• CPD residuals are equal to the logarithms of CUP-ratiosRelation between CUP-Ratios and CPD residuals

Relation betweenQuaranta and Dikhanov Tables

• Dikhanov Tables can be compiled for a group of BHs (an aggregate), they use color schemes to highlight potential outliers and can be collapsed to present only residuals for items• Quaranta tables presents the relations within an item potentially clearer

0 to 14 14 to 47 47 to 78 78 to 128 128 to 212 212 to 739 739 to

Less than -2.0

-2.0 to -0.75

-0.75 to -0.25

-0.25 to 0.25

0.25 to 0.75 0.75 to 2.0 More

than 2.0CPD residuals

CUP-Ratios

2121

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