Quality-corrected price indices: the case of the Dutch new passenger car market, 1990–1999

Market dynamics and technological developments constitute a major challenge to the proper measurement of the price evolution of durable goods. In this study, hedonic methods are used to estimate quality-corrected price indices of new passenger cars in the Netherlands, 1990–1999. Use is made of a huge set of price, quantity and quality information about 11,000 car models, obtained from different sources. During the observation period the nominal price level of all available car models increased about 20% on average, while the shares of car models with airbags, tinted glass and power steering increased from almost nothing to about 90%. Matched model price indices and the official CPI for new passenger cars, which partially account for quality-adjustments, estimate the price increase to be equal to 10.6–14.2% respectively 11.2% for the 1990–1999 period. By contrast, the hedonic Fisher-like price indices based on the preferred annually estimated brand-weighted semi-log hedonic model, lead to price changes varying from +?2.3% to ??3.4% (depending on the choice of weight variable, and the use of fixed or varying reference periods in the index construction) and thereby fall 8.9 to 14.6 percentage points below the official figures, over the period 1990–1999. The pooled adjacent-years model holds an intermediate position with a predicted quality-corrected price decrease of 1.8% over the observation period, which is 13.0 points below the CPI.     

Life Cycle Price Trends and Product Replacement: Implications for the Measurement of Inflation

The paper explores the extent to which products follow systematic pricing patterns over their life cycle and the impact this has on the measurement of inflation. Using a large U.S. scanner data set on supermarket products and applying flexible regression methods, we find that on average prices decline as items age. This life cycle price change is often attributed to quality difference in the construction of CPI as items are replaced due to disappearance or during sample rotations. This introduces a systematic bias in the measurement of inflation. For our data we find that the life cycle bias leads to the underestimation of inflation by around 0.30 percentage points each year for the products examined.     

The Effects of New Goods and Substitution on the Korean CPI as a Measure of Cost of Living

This paper estimates upper-level substitution and new-goods bias in the Korean Consumer Price Index (CPI) from the early 1990s to the mid 2000s. It has been estimated that the upper-level substitution bias in the CPI alone increased the inflation rate by 0.51 percentage points per year over the 13-year period between 1990 and 2002. The new-goods bias further increased the inflation rate by 0.17 and 0.13 percentage points per year between 1990-1995 and 1995-2000 respectively. The Chained Laspeyres index series that is based on annually-updated weights has been found to correct less than half of the upper-level substitution bias.     

The Laspeyres bias in the Spanish consumer price index

The CPI compares the cost of acquiring a reference quantity vector at current and base prices. Such reference vector is the vector of mean quantities actually bought by a reference population, whose consumption patterns are investigated during a period τ prior to the index base period 0. This paper shows that unless the price change between these two dates is taken into account, the CPI ceases to be a proper statistical price index of the Laspeyres type. Among several negative consequences, the most important is that this omission produces a bias in the measurement of inflation: the ‘Laspeyres bias’. Using Spanish data, the size of the Laspeyres bias is estimated at -0.061% per year, during 1992–1998. The Laspeyres bias in shorter time periods reached -0.122% per year in 1992, and -0.108 in 1997.     

Econometric analysis of price index for home video cassette recorders in the U.S., 1978-1987

This paper conducts an empirical analysis on the U.S. VCR market using a hedonic approach. The paper finds that quality-adjusted price indices decline at 11-12% per year, with a large annual drop of about 18% from 1982-85. Estimation and data analysis reveal interesting aspects of the evolution of quality and price in the VCR market. As a result of the exclusion of the VCR category until 1986, the paper estimates a bias of 2.4% per year in the CPI electronics subindex.     

CPI Quality Adjustment and Productivity Growth: Railway Services in Japan

In recent years quality adjustment of price indices has been vigorously explored and the hedonic regression method has become popular in official statistics. In service sectors, however, the current CPI seems not to have been successfully adjusted to accommodate quality changes. In this paper I focus on the railway industry in Japan, where quality change is a vital factor in the measurement of price indices and productivity. Using hedonic regressions to adjust CPI railway fares, the paper suggests that there may be a significant degree of upward bias in the current CPI railway fares. Also, this leads to the results that the total factor productivity (TFP) of the Japanese railway industry, which is calculated by using the newly adjusted CPI as a deflator, has been improved contrary to previous research on this issue.     

Effects of mineral-commodity price shocks on monetary policy in developed countries

This article investigates effects of changes in mineral commodity prices on monetary policy. Using macroeconomic data from three mineral-producing countries (Australia, Canada and New Zealand) and two non-mineral-resource countries (USA and UK), I estimate the impulse response functions of the policy interest rates and the core consumer price index (CPI) inflation rates to mineral-commodity price shocks. I find that the central banks in both groups of the examined countries significantly respond to mineral-commodity price shocks. In responses to an unexpected 10% increase in mineral commodity prices, the central banks are estimated to increase their policy interest rates by approximately 0.8 percentage points. Moreover, the central banks seem to take anticipatory policy reactions to control core CPI variations triggered by these shocks. Thus, mineral commodity prices would act as important determinants of the monetary policies in both groups of the examined countries. These findings would be useful for analysing Taylor rules in their countries. However, effects of the increase in their policy interest rates on core CPI inflation cannot be identified for the examined countries.     

消费者价格指数与生产者价格指数:谁带动谁?

消费者价格指数(CPI)与生产者价格指数(PPI)是相互联系并有显著区别的概念。两者之间的因果关系或非因果关系有多种可能情形。本文对中国消费者价格指数(CPI)和生产者价格指数(PPI)2001年1月至2008年7月数据的格兰杰因果检验结果显示,在所考察时期内,消费者价格指数是生产者价格指数变动的格兰杰原因,后者经过1—3个月左右的时滞对前者的变动作出反应。这个结果很可能意味着,在所考察时期内,在影响以消费者价格指数(CPI)来衡量的国内通货膨胀中,需求方面的因素相对大于供给方面的作用,尽管需求因素和供给因素都共同地影响了国内通货膨胀的走势。     

Scenarios for a redistribution of unpaid work in the Netherlands

The consumer price index (CPI) is used in the United States to measure changes in the cost of living. Since the CPI is used to index the official U.S. poverty guidelines and to establish eligibility criteria for various public assistance programs, a change in the methodology used to calculate the CPI would impact the accuracy of poverty statistics and, more importantly, poor families' access to public assistance. Since the majority of these poor families are headed by women, the CPI becomes a critical issue for feminist economics. In December 1996 the United States Senate Finance Committee's Advisory Commission to Study the Consumer Price Index issued its final report which concluded that use of the consumer price index results in widespread substantial overindexing. This paper uses the basic needs budgets (BNB) to evaluate changes in the cost of living for low-income families. The author compares the cost of the BNBs for single-parent families in 1983 and 1996 and finds that the cost of the bundle of goods and services included in the BNBs has increased faster than the CPI. The author finds similar results for two-parent families.     

Prices and social behaviour: Evidence from adult smoking in Canadian Aboriginal communities

This paper provides estimates of tobacco price elasticity explicitly distinguishing between two price effects: the direct effect, reflecting individual reaction to a price change, and the indirect effect, whereby price influences the individual by changing community smoking behaviour. Canada's Aboriginal communities are small and secluded, allowing for plausible identification of reference groups on a relatively large scale. Estimates suggest a 10% increase in price decreases daily smoking by 0.91 percentage points (2.11%), occasional smoking by 1.24 percentage points (8.27%) and average smoking intensity by 0.15 cigarettes per day (2.9%). It is found that the indirect effect almost doubles the response to a change in tobacco prices over the direct effect alone.     

消费者价格指数能反映生活成本吗 基于城镇各收入阶层食品生活成本估计

本文基于超级指数和可变偏好效用函数方法构建了1997-2011年中国城镇各收入阶层家庭食品消费生活成本指数,并在此基础上将各阶层生活成本指数与其消费者价格指数进行对比,检验消费者价格指数对生活成本的反映能力。样本期间内消费者价格指数与生活成本指数比较接近,可以较好地反映生活成本的变化。基于超级指数方法的结果显示,样本期间内替代偏差与家庭收入负相关,与通货膨胀正相关,而由于偏好改变所造成的偏差在绝对值水平上则与收入水平正相关。     

消费物价指数与生产者价格指数:谁带动谁?

The consumer price index (CPI) and producer price index (PPI) are interrelated but significantly different concepts. Relationships between the two indices may be that of causality or non-causality. The paper conducts a Granger-causality test on China’s CPI and PPI data for the period from January 2001 to August 2008, and finds that CPI Granger causes the change in PPI, and the latter reacts to the former with a time lag of 1–3 months. The result may suggest that in contemporary Chinese economy, demand-side factors have played a more important role than supply-side factors, although the two sides both have influences on domestic inflation trend which is measured by CPI. __________ Translated from Jingji Yanjiu 经济研究 (Economic Research Journal), 2008, (11): 16–26     

Inflation processes in poland during the transformation period

From 1989 to 1997, the price of goods and consumer services rose very quickly under the influence of strong inflationary processes that took place in the Polish economy. Those processes were also present during the time of a centrally controlled economy. However, they did not appear as an open price inflation. This paper presents an analysis of inflationary processes before and during the transformation period. Special attention is paid to measuring inflation and to the utilization value of indices used for this kind of analysis. The most popular measure of inflation is the consumer price index (CPI). This paper presents a few examples of the many uses of the CPI. The focus is on the interpretation of this index which has special characteristics for the systemic transformation period taking place in Poland.     

Cost-of-living indexes and demographic change

The Consumer Price Index (CPI), although not without problems, is the most often used mechanism for adjusting contracts for cost-of-living changes in the US. The US Bureau of Labor Statistics lists several problems associated with using the CPI as a cost-of-living index where the proportion of 2-worker families is increasing, population is shifting, and work week hours are changing. This study shows how to compute cost-of-living indexes which are inexpensive to update, use less restrictive assumptions about consumer preferences, do not require statistical estimation, and handle the problem of increasing numbers of families where both the husband and wife work. This study attempts to how widely in fact the CPI varies with alternative true cost-of-living varies with alternative true cost-of-living indexes although in the end this de facto cost-of-living measure holds up quite well. In times of severe price inflation people change their preferences by substitution, necessitating a flexible cost-of-living index that accounts for this fundamental economic behavior.     

Is there a quality bias in the Canadian CPI? Evidence from microdata

Rising consumer prices may reflect shifts by consumers to new higher‐priced products, mostly for durable and semi‐durable goods. I apply Bils’ (2009) methodology to newly available Canadian consumer price data for non‐shelter goods and services to estimate how price increases can be divided between quality growth and price inflation. I find that less than one third of observed price increases during model changeovers should be attributed to quality growth. This implies overall price inflation close to inflation measured by the official index. I conclude that, according to Bils’ methodology, the quality bias is not an important source of potential mismeasurement of CPI inflation in Canada.     

Do disaggregated CPI data improve the accuracy of inflation forecasts?

In this paper, we evaluate the role of using consumer price index (CPI) disaggregated data to improve the accuracy of inflation forecasts. Our forecasting approach is based on extracting the factors from the subcomponents of the CPI at the highest degree of disaggregation. The data set contains 54 macroeconomic series and 243 CPI subcomponents from 1992 to 2009 for Mexico. We find that the factor models that include disaggregated data outperform the benchmark autoregressive model and the factor models containing alternative groups of macroeconomic variables. We provide evidence that using disaggregated price data improves forecasting performance. The forecasts of the factor models that extract the information from the CPI disaggregated data are as accurate as the forecasts from the survey of experts.     

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.     

基于核心通货膨胀视角的 物价走势判定研究*

核心通货膨胀对于央行准确判定物价走势、更好实现稳定物价目标具有重要意义。本文采用广义动态因子模型与频谱分解技术测度的核心通货膨胀相比于CPI通胀率能更准确反映我国物价变动的周期特征与长期趋势,对于央行更合理地引导社会公众的通胀预期,实现物价稳定与产出稳定的动态平衡具有一定的参考价值。鉴于中国转型时期通胀因素的叠加性与复杂性,本文还提出金融宏观调控应综合考虑包括核心CPI、CPI在内的多种通货膨胀指标,在维持长期物价稳定的同时,兼顾物价的短期波动。     

The Impact of a Marginal Cost Increase on Price and Quality: Theory and Evidence from Airline Market Strikes

This paper examines the impact of a marginal cost increase for one firm on price and quality in a duopoly market. The results are derived theoretically and then tested empirically. The marginal cost increase is interpreted as an increase in the wage one firm pays its workers. The predictions are tested with two United States airline strikes during the 1990's. Quality is proxied in three ways: (1) the number of flights per day, (2) the percentage of flights cancelled, and (3) the percentage of flights arriving late. The results show that the strike coefficients for the effects on quality are most consistent with theoretical predictions when quality is measured as the number of flights per day. These results are encouraging because of the three measures of quality, it seems that number of flights per day is the measure of quality that is most controllable by the .rm. The strike coefficients for the direct effect on price are most consistent with theoretical predictions when quality rankings are determined by the percentage of flights cancelled. The strike coefficients for the total effect on price are most consistent with theoretical predictions when quality rankings are determined by the percentage of flights arriving late.     

我国粮食价格与CPI关系研究

本文利用1998年1月-2010年10月的月度CPI数据和粮食批发价格指数对粮食价格和CPI的关系进行了定性和定量分析。实证结果表明,两者之间存在长期和短期关系,从长期来看,粮食价格每上涨1%会使CPI上涨0.336%;从短期来看,粮价对CPI有滞后1期的影响,CPI对粮价有滞后3期的影响。综合考虑影响粮食价格的国际效应、供给效应、市场预期效应和政策效应,未来几个月我国粮价将有所上涨,但涨幅不会很大。