Estimating Quality‐adjusted Price Changes: Method and Application to VCRs

This paper uses scanner data to generate estimates of quality‐adjusted price changes for video‐recorders. We use hedonic regressions to derive estimates of the changing worth of each quality component. These are then applied to weighted changes in the mix of quality attributes of products to derive estimates of quality‐adjusted price (QAP) changes. The data source used is electronic‐point‐of‐sale (EPOS) scanner data that are available for a wide range of goods. This study provides an example of how such methods can be more widely applied. The estimates of QAP changes correspond to constant‐utility, (hedonic) cost‐of‐living indexes defined in economic theory as the ratio of expenditure functions at constant utility allowing for changing prices and characteristics of goods. This method is proposed as an improvement on the existing direct method , which takes its estimates directly from the coefficients associated with 'time dummies' in a hedonic regression. We finally undertake a matching process, akin to that used by statistical offices, and compare the results. Direct comparisons with RPI estimates and these hedonic approaches are not easy since the approaches use quite different data sets. Our replication of a procedure akin to that used for the RPI on the scanner data set provides insights into sources of potential bias.     

Scanner Data and the Measurement of Inflation

This paper outlines the potential use of bar-code scanner data from retailers for the measurement of inflation. The source benefits from its extensive coverage in providing data on prices, quantities and values of transactions of each model of a good sold. Relative weights can thus be ascribed to price changes in both base and current months at a highly detailed level which allows us to estimate substitution bias. Methods of adjusting for quality changes can be considered. The dummy variable hedonic approach is compared with a superlative, exact hedonic approach and a matching technique akin to that used by statistical offices.     

基于享乐价格理论的旅游产品定价研究

基于享乐价格理对旅游景区的价格竞争力进行分析。首先根据旅游产品的特性构建景区价格评价体系,同时对分析指标进行分类量化;其次利用SPSS 17.0对所研究的旅游景区的面板数据进行多元回归分析,构建最优享乐价格模型。研究得出的结论为:景区林木覆盖率,水质,气候,景区基础设施,服务环境,景区级别,景区面积,导游受教育程度,景区的审美价值可以用来较好的解释景区的价格竞争力问题。     

Estimating exact hedonic indexes: An application to UK television sets

Much attention has been given to the estimation of hedonic regressions given their potential use as a means to adjust consumer and producer price indices for quality changes. However, there has been warranted criticism over the methods used, particularly relating to the econometric specification of the models. Much of the criticism has arisen from the inability of available data to match the requirements of a fully specified model. Using EPOS scanner data for UK television sets we provide reliable hedonic estimates which incorporate several developments. Such data are available for a wide range of product areas and this application illustrates how they might be used. We develop methodology to help surmount problems arising from omitted variables, the coexistence of new and old models, weighting of observations and quality changes common to all models. More specifically we pay particular attention to the neglected area of product markets where pricing is above marginal cost.     

The product life cycle and sample representativity bias in price indexes

Official price indexes are usually calculated using matched samples of products. If products exhibit systematic price trends at different points in their life cycle then matched sample methods may introduce bias if the life cycle movement in the sample does not adequately reflect that in the population. This article explores the extent of these life cycle pricing effects and then examines the bias it can introduce in measured inflation. A large US supermarket scanner data set for six cities and six products over 12 years is used. Using hedonic methods we find that the life cycle component of price change is important across a range of products and cities. To explore the bias introduced by these movements, we use simulations that construct indexes with different sample update frequency. For indexes that are never completely resampled, we find an annual absolute bias of 0.88 and 0.59 percentage points depending upon whether we use the actual prices or prices imputed from our hedonic model. This compares with absolute biases of 0.34 and 0.10 percentage points for the corresponding cases for samples, which are re-selected annually. Thus our results provide strong support for more frequently updating index samples.     

特征价格模型的发展应用研究

特征价格模型因为其完美的理论思想而成为国际上普遍使用的分析异质品价格和特征关系的主要方法.本文通过对国外核心期刊上一百五十二篇特征价格法相关文献的检阅,梳理了国内外特征价格模型及指数编制的研究现状,对特征价格模型的功能进行了总结性定位,认为特征价格模型的功能主要在于:异质品价格指数的编制,异质品价格预测、价值评估或产品定价,异质品价格影响因素分析,非市场因素的经济效应的检验及对传统经济学模型的改进五方面.文章最后以住宅为例,归纳总结了特征价格法在研究应用中存在的主要问题:一是市场细分;二是特征变量选择和量化;三是模型形式选择;四是模型估计方法的研究;五是指数编制中的问题.这些研究对象为未来特征价格的研究提供了可行参考.     

Alternative Land-Price Indexes for Commercial Properties in Tokyo

The System of National Accounts (SNA) requires separate estimates for the land and structure components of a commercial property. Using transactions data for the sales of office buildings in Tokyo, a hedonic regression model (the “builder’s model”) was estimated and this model generated an overall property price index as well as subindexes for the land and structure components of the office buildings. The builder’s model was also estimated using appraisal data on office building real estate investment trusts (REITs) for Tokyo. These hedonic regression models also generated estimates for net depreciation rates, which can be compared. Finally, the Japanese government constructs annual official land prices for commercial properties based on appraised values. The paper compares these official land prices with the land prices generated by the hedonic regression models based on transactions data and on REIT data. The results reveal that commercial property indexes based on appraisal and assessment prices lag behind the indexes based on transaction prices.     

Chained,exact and superlative hedonic price changes: estimates from microdata

Scanner data are used to calculate chained, exact (and superlative) hedonic price indexes for television sets. The data source is available for a wide range of goods, the application providing an example of how this method can be more widely applied. The indexes correspond to constant utility, hedonic cost-of-living indexes. The approach improves on the existing direct method, which takes its estimates directly from the coefficients on time dummies in a hedonic regression. It also improves on the matched model method used by statistical agencies. The differences between actual price changes and exact hedonic quality-adjusted price changes are found to be substantial. Base-period and current-period weighted exact hedonic indexes are similar, thus providing good approximations to a superlative index. Estimates from the direct, dummy variable approach were compared to the superlative indexes. The disparities between the results argue for caution in the use of the direct, dummy variable approach to estimating quality-adjusted price changes.     

ELEMENTARY AGGREGATES, MICRO-INDICES AND SCANNER DATA: SOME ISSUES IN THE COMPILATION OF CONSUMER PRICE INDICES

The paper argues for the use of scanner data from EPOS systems for use in the compilation of consumer price indices. A number of methods of calculating micro-indices from such data are outlined. Scanner data for colour television sets in the U.K. are used as an example. The Tornqvist chained index is used as a benchmark against which alternative formulations, including those based on representative products, can be judged, the errors often being substantial. The paper argues for the use of scanner data, illustrates methods of compiling micro-indices and points to the potential for serious errors from conventional methods.     

An Application of the Hedonic Price Model to the Perth Residential Land Market*

This paper presents the results of an application of the Rosen-Freeman hedonic price model to the Perth (Western Australia) residential land market. A sample of over two thousand market transactions is used to estimate the value of residential land attributes. Major emphasis is given to those particular land attributes that are subject to public regulation and to the policy implications that follow.     

ACCOUNTING FOR THE EFFECTS OF NEW AND DISAPPEARING GOODS USING SCANNER DATA

With the "discovery" of scanner data by statistical agencies and researchers comes a wealth of new information upon which price index calculations can be based. Old problems, such as the appearance and disappearance of goods over time, are likely to be an important feature of such data. However, given that scanner data includes the prices and quantities of the population of transactions we have more information than is traditionally available to deal with the new and disappearing goods problem. We adopt a recently developed approach using the Constant Elasticity of Substitution cost function to provide a detailed empirical analysis of the effects of new and disappearing goods for an Australian scanner data set of supermarket products. Our results indicate that the failure to account for new and disappearing goods in the cost-of-living index leads to a significant upward bias.     

Understanding Price Variation Across Stores and Supermarket Chains: Some Implications for CPI Aggregation Methods

The empirical literature on price indices consistently finds that aggregation methods have a considerable impact, particularly when scanner data are used. This paper outlines a novel approach to test for the homogeneity of goods and hence for the appropriateness of aggregation. A hedonic regression framework is used to test for item homogeneity across four supermarket chains and across stores within each of these supermarket chains. We find empirical support for the aggregation of prices across stores which belong to the same supermarket chain. Support was also found for the aggregation of prices across three of the four supermarket chains.     

Environmental amenities and agricultural land values: a hedonic model using geographic information systems data

Remote agricultural lands, which include wildlife habitat, angling opportunities and scenic vistas, command higher prices per hectare in Wyoming than those whose landscape is dominated by agricultural production. Geographic information systems (GIS) data are used to measure recreational and scenic amenities associated with rural land. A hedonic price model is specified with GIS measures. It is used to estimate the impact of amenity and agricultural production land characteristics on price per acre for a sample of Wyoming agricultural parcels. Results indicate that the specification performed well across several functional forms. The sampled land prices are explained by the level of both environmental amenities as well as production attributes. Statistically significant amenity variables included scenic view, elk habitat, sport fishery productivity and distance to town. This analysis permits a better estimation of environmental amenity values from hedonic techniques. Improved estimation of amenity values is vital for policies aimed at open space preservation, using agricultural conservation easements and land use conflict resolution.     

Prohibitions,price caps,and disclosures: A look at state policies and alternative financial product use

This study uses nationally representative data from the 2009 National Financial Capability State-by-State Survey to examine the relationship between state-level alternative financial service (AFS) policies (prohibitions, price caps, disclosures) and consumer use of five AFS products: payday loans, auto title loans, pawn broker loans, refund anticipation loans, and rent-to-own transactions. Looking across products rather than at one product in isolation allows a focus on patterns and relationships across products. The results suggest that more stringent price caps and prohibitions are associated with lower product use and do not support the hypothesis that prohibitions and price caps on one AFS product lead consumers to use other AFS products.     

城市住宅特征价格分析:对杭州市的实证研究

由于住宅产品的异质性,国外学者广泛使用特征价格模型分析城市住宅市场。特征价格模型的理论基础主要由Lancaster偏好理论和Rosen的产品特征市场供需均衡模型两部分组成。在访谈的基础上,选择了18个住宅特征作为模型的自变量,基于线性函数形式构建了杭州市住宅特征价格模型。采用杭州市2 473个住宅样本数据和290个住宅小区的实地调查资料对模型进行了估计,发现就整个住宅市场而言,14个住宅特征对住宅价格具有显著影响,并且影响程度有差异。同时,根据特征价格对14个住宅特征的影响程度进行了排序,并分为四类。     

A computer software price index using scanner data

Abstract.  In the last 20 years, the expenditure share of prepackaged software in the national output has grown. The large number of characteristics in computer software make hedonic regression techniques impractical for purposes of controlling for quality changes. In this study, matched model price indices are constructed using monthly scanner data on prices and unit values for various prepackaged computer software titles and categories sold in Canada from January 1996 to June 2000. Quality differences are controlled for by applying the maximum overlap method. Results show that prices declined during the period studied at an average annual rate of 5.9%. JEL classification: C43, L86     

Approaches to performance measurement in hedonic analysis: Price indexes for laptop computers in the 1990's

This paper estimates price indexes for laptop personal computers using hedonic methods and data taken from PC Magazine technical reviews. We use benchmark test results to construct a measure of system performance that encapsulates factors that have previously gone unmeasured, such as the interactions between hardware components. The resulting hedonic function is parsimonious yet has good explanatory power. A second approach to performance measurement is developed using a set of technical proxies that are shown to closely approximate the benchmark test scores, and are thus nearly perfectly equivalent in terms of resulting price index estimates. While not as parsimonious as a single performance measure, these proxies have the advantage of not requiring direct performance testing, and could thus be applied to larger data sets. Laptops were found to have declined in quality-adjusted price at an average rate of 40% per year for the period 1990-1998.     

WEIGHTED COUNTRY PRODUCT DUMMY VARIABLE REGRESSIONS AND INDEX NUMBER FORMULAE

The article considers a very simple type of hedonic regression model where the only characteristic of a commodity is the commodity itself. This regression model is known as the country product dummy method for calculating country price parities in the context of making international comparisons. The paper considers only the two country or two period case and introduces value or quantity weights into the regression. The resulting measures of overall price change between the two countries or time periods are compared to traditional bilateral index number formulae. It is shown how the Geary Khamis, Walsh and Törnqvist price indexes can be obtained as special cases of this framework.     

Gasoline demand in the OECD: An application of pooling and testing procedures

This study utilizes a pooled inter-country data set, finding the long-run price-elasticity falls in the range ?0.55 to ?0.9, depending on the choice of pooled estimators. The estimators included the OLS, within-, and between-country estimators, plus five feasible GLS estimators. Even allowing for a ten-year distributed lag on price to reflect changes in auto-efficiency characteristics, the within-country estimator yields appreciably more inelastic estimates than did the O:S estimator, which was heavily influenced by the between- or inter-country variation. This difference raises intriguing questions for future research.     

A simple model for study of the determination of the price level and the interaction of monetary and fiscal policy

Summary A representative-agent model with money holdings motivated by transactions costs, a fiscal authority that taxes and issues debt, no production, and a convenient functional form for agents' utility is presented. The model can be solved analytically, and illustrates the dependence of price determination on fiscal policy, the possibility of indeterminacy, even stochastic explosion, of the price level in the face of a monetary policy that holdsM fixed, and the possibility of a unique, stable price level in the face of a monetary policy that simply pegs the nominal interest rate at an arbitrary level.In a rational expectations, market-clearing equilibrium model with a costlessly-produced fiat money that is useful in transactions, the following things are true under broad assumptions.- A monetary policy that fixes the money stock may (depending on the transactions technology) be consistent with indeterminacy of the price level—indeed with stochastically fluctuating, explosive inflation.- A monetary policy that fixes the nominal interest rate, even if it holds the interest rate constant regardless of the observed rate of inflation or money growth rate, may deliver a uniquely determined price level.- The existence and uniqueness of the equilibrium price level cannot be determined from knowledge of monetary policy alone; fiscal policy plays an equally important role. Special case models with interest-bearing debt and no money are possible, just as are special cases with money and no interest-bearing debt. In each the price level may be uniquely determined.Determinacy of the price level under any policy depends on the public's beliefs about what the policy authority would do under conditions that are never observed in equilibrium.These points are not new. Eric Leeper [1991] has made most of them within a single coherent model. Woodford [1993], in a representative agent cash-in-advance model, has displayed the possibility of indeterminacy with a fixed quantity of money and the possibility of uniqueness with an interest-rate pegging policy. Aiyagari and Gertler [1985] use an overlapping generations model to make many of the points made in this paper, without discussing the possibility of stochastic sunspot equilibria. Sargent and Wallace [1981] and Obstfeld [1983] have also discussed related issues.This paper improves on Leeper by moving beyond his analysis of local linear approximations to the full model solution, as is essential if explosive sunspot equilibria are to be distinguished from explosive solutions to the Euler equations that can be ruled out as equilibria. It improves on the other cited work by pulling together into the context of one fairly transparent model discussion of phenomena previously discussed in isolation in very different models.We study a representative agent model in which there is no production or real savings, but transactions costs generate a demand for money. The government costlessly provides fiat money balances, imposes lump-sum taxes, and issues debt, but has no other role in the economy. We make restrictive assumptions about the form of the utility function and the form of a transactions cost term in the budget constraint.The model could be extended to include production, capital accumulation, non-neutral taxation, productive government expenditure, and a more general utility function without affecting the conclusions discussed in this paper. Indeed the model I informally matched to data in an earlier paper [1988] makes some such extensions. While such an extended model is more realistic, it is harder to solve. The version in my earlier paper [1988] was solved numerically and simulated. The bare-bones model of this paper allows an explicit analytic solution that may make its results easier to understand.This paper improved following comments from participants at seminars at Yale and the Atlanta Federal Reserve Bank. Eric Leeper and James Robinson were particularly helpful. Comments from Michael Woodford led to important corrections and clarifications.