Multi-category purchase incidences with marketing cross effects

We focus on cross effects of marketing variables and cross category dependences for multi-category decisions which households take during a shopping trip to a retail store. A cross effect is defined as the effect which a marketing variable used for a certain product category exerts on purchases of another category. Using Dirichlet process mixture models with multivariate probit components we analyze purchase incidences of 24,047 shopping visits of a random sample of 1500 households. Independent variables of these models encompass marketing variables for 25 product categories and household attributes. We discuss differences between the two best performing models, a full model which includes both cross effects and cross category dependences, and a related restricted model which ignores cross effects. We obtain several high and significant differences with respect to category constants and cross category dependences between these two models. We also present explanations for the larger (in absolute terms) cross effects of features or displays. We demonstrate that by ignoring cross effects management runs the risk to obtain in many product categories too optimistic forecasts of sales revenue changes due to promotions. In contrast to previous related work suggesting not to use promotions which are not tailored to individual households in any of the investigated categories, we obtain support for such promotions in at least 48 % of the 25 product categories. In addition, based on the full model we demonstrate that often different categories are appropriate for promotions which are targeted at household clusters.     

Advance selling with freebies and limited production capacity

We consider a two-period pricing model in which a seller offers freebies along with the product when making advance sales, and production is constrained by capacity. The seller can offer freebies to increase both market base and customer׳s valuation toward the product in advance. The customers strategically determine whether to purchase the product in advance and gain freebies when their valuation on the product is uncertain, or delay their purchase decision until the regular selling period. We characterize the optimal pricing, quality level of the freebie and production quantity decisions that maximize the expected profits of the seller over the two periods.     

A LOGIT-MARKOVIAN MODEL OF CONSUMER PURCHASE BEHAVIOR BASED ON EXPLANATORY VARIABLES: EMPIRICAL EVALUATION AND IMPLICATIONS FOR DECISION MAKING*

This study describes and empirically evaluates an approach to modeling purchase behavior that integrates a Logit-Markov-based multivariate brand-choice model structure with stochastic components. Using actual market data for a frequently purchased consumer product obtained from a consumer purchase panel survey, the paper highlights some marketing applications of the model. Given its general structure, the model can aid marketing managers in defining and evaluating target market segments and in assessing the impact of alternative marketing strategies.     

面临零部件过期的产品销售与售后服务供应链合同分析

备件库存管理对产品售后服务至关重要,而零部件过期会影响备件库存的正常补货,进而延长故障修复时间,降低产品可用率.终身购买作为应对零部件过期的重要策略,被广泛运用在实践中.然而,学术论文中关于零件过期对供应链管理影响的研究并不多见.本文建立了同时考虑产品销售和售后服务情况下的供应链动态博弈模型,分析了客户的产品订购批量、供应商的定价决策以及备件终身购买批量之间的相互作用,探讨了保修期和零部件过期采购成本对合同均衡策略和供应链利润的影响.结果表明,当零部件过期采购成本较低时,供应商可以在延长保修期的同时降低备件库存数量,并允许一定程度的备件缺货水平,从而最大化提升产品可用率所带来的收益.同时,应当适当降低对备件数量的技术标准要求.而当零部件过期 采购成本较高时,供应商应当避免提供较长的保修期,并增加备件终身购买批量以减小零部件过期带来的负面影响.此时,备件数量的技术标准则可以适当提高.     

Analyzing the dependences of multi-category purchases on interactions of marketing variables

We extend the usual specification of the multivariate probit model frequently used to analyze multi-category purchase incidence data by introducing interaction effects between marketing variables. Models are estimated by a Markov Chain Monte Carlo simulation method using 24,047 shopping visits made by a random sample of 1500 households in one specific grocery store over a one year period. Our data refer to a total of 25 food and non-food product categories and include socio-demographic household attributes in addition to purchases and marketing variables. Information criteria agree on the superiority of the extended specification. Estimation results demonstrate that many interaction effects are erroneously attributed to the main effects of marketing variables if one applies the usual specification instead. We derive managerial implications with respect to sales revenue by stochastic simulation. If managers base decisions on the usual specification in spite of its worse statistical performance, they run the risk to overestimate sales revenue increases due to sales promotion activities.     

Optimal Pricing,Ordering, and Return Policies for Consumer Goods

Our research addresses a firm that sells a product to consumers who are sensitive to both price and return policy. The operational decisions of interest are the selling price, return policy, and quantity of new product to purchase. We model a single selling season that is split into two periods where the boundary between periods is delineated by the opportunity to recover product returns and resell them. That is, returns in the first period can be recovered and sold in the second period. Returns also arise in the second period, but these may only be salvaged. We first analyze both deterministic and stochastic models, finding that the deterministic results largely carry over to the stochastic case. In addition, our results indicate that the model is quite insensitive to errors in the estimates of the parameter values, except for purchase cost and parameters related to demand. Finally, we perform an analysis on the value of various investments to improve financial performance. Results indicate that investments to reduce the recovery cost of returns or reduce returns uncertainty are minimal, while investments to increase recovery speed, reduce market uncertainty, and reduce the return rate can be quite valuable.     

基于波动择时绩效的高维波动率估计量与预测模型研究

对协方差矩阵高频估计量和预测模型的选择，共同影响协方差的预测效果，从而影响波动择时投资组合策略的绩效。资产维数很高时，协方差矩阵高频估计量的构建会因非同步交易而丢弃大量数据，降低信息利用效率。鉴于此，将可以充分利用资产日内价格信息的KEM估计量用于估计中国股市资产的高维协方差矩阵，并与两种常用协方差矩阵估计量进行比较。进一步地，将三种估计量分别用于多元异质自回归模型、指数加权移动平均模型以及短、中、长期移动平均模型进行样本外预测，并比较在三种基于风险的投资组合策略下的经济效益。采用上证50指数中20只不同流动性成份股逐笔高频数据的实证研究发现：（1）无论是在市场平稳时期还是市场剧烈震荡期，长期移动平均模型都是高维协方差估计量预测建模的最优选择，在应用于各种波动择时策略时都可以实现最低成本和最高收益。（2）在市场平稳时期，KEM估计量是高维协方差估计的最优选择，应用于各种波动择时策略时基本都可以实现最低成本和最高收益；在市场剧烈震荡期，使用KEM估计量进行波动择时仍然可以在成本方面保持优势，但在收益上并不占优。（3）无论是在市场平稳时期还是市场剧烈震荡期，最低的成本都是在采用等风险贡献投资组合时实现的，而最高的收益则都是在采用最小方差投资组合时实现的。研究不仅首次检验了KEM估计量在常用波动择时策略中的适用性，而且首次实证了实现最为简单的长期移动平均模型在高维协方差矩阵预测中的优越性，对投资决策和风险管理等实务应用都具有重要意义。     

网络销售中退货担保与定价决策

本文采用退货担保期权综合完全退货策略与部分退货策略的优点,构建了网络销售中基于期权的退货与定价模型,以商品的价格、退货策略和退货担保期权价格为决策变量,讨论了存在退货期权和不存在退货期权两种情况下,最优决策存在的条件,求解出销售商最优价格、退货策略和退货担保期权价格,分析了各个市场参数变化对最优值的影响,通过对担保退货期权与退货策略同时存在和购买期权才能退货二种策略的比较,发现供应商最优策略是前者。算例验证了以上结论,做了敏感性分析,总结了相关管理启示与未来研究方向。所得结论对网络销售商开展网上销售有重要参考价值。     

Modeling whether,what and how much to buy the right way: an empirical analysis with implications for model building

Whether, what and how much to buy are central decisions in consumer goods markets. Marketing research commonly uses a sequential approach where quantity decision is conditional on purchase incidence and brand choice (e.g., Ailawadi et al. in J Mark Res 44:450–467, 2007). This approach assumes separability between decisions and suffers from selectivity bias. The bias can be overcome by explicitly controlling for it (e.g., Zhang et al. in Rev Mark Sci 3(1), 2005) or by using one unifying utility function, a method considered “state of the art in analyzing purchase behavior in a single product category” (e.g., Song and Chintagunta in J Mark Res 44(4):595–612, 2007). However, this latter method puts restrictive assumptions on the influence of prices on choices, which may affect managerial implications derived from the model results. This study investigates the effect of selectivity bias by comparing the sequential approach—with and without explicitly controlling for endogeneity bias—to the unifying utility function approach. Based on household panel data from three categories, we illustrate the extent to which managerial implications from these frameworks differ. We show that the superiority of one framework versus the other depends on the specific category and its characteristics. The managerial implications of using the “wrong” framework are demonstrated by conducting two simulation studies; these show that price elasticities substantially deviate across frameworks.     

Equilibrium Joining Strategies and Optimal Control of a Make‐to‐Stock Queue

We consider a make‐to‐stock, finite‐capacity production system with setup cost and delay‐sensitive customers. To balance the setup and inventory related costs, the production manager adopts a two‐critical‐number control policy, where the production starts when the number of waiting customers reaches a certain level and shuts down when a certain quantity of inventory has accumulated. Once the production is set up, the unit production time follows an exponential distribution. Potential customers arrive according to a Poisson process. Customers are strategic, i.e., they make decisions on whether to stay for the product or to leave without purchase based on their utility values, which depend on the production manager's control decisions. We formulate the problem as a Stackelberg game between the production manager and the customers, where the former is the game leader. We first derive the equilibrium customer purchasing strategy and system performance. We then formulate the expected cost rate function for the production system and present a search algorithm for obtaining the optimal values of the two control variables. We further analyze the characteristics of the optimal solution numerically and compare them with the situation where the customers are non‐strategic.     

The newsvendor problem with barter exchange

Barter exchange, as an alternative to move distressed inventory, has become increasingly popular in business. Many companies barter their unsold product for the product they need via barter exchange platforms at full prices. In this paper we consider the newsvendor problem with the barter exchange option. A retailer (the newsvendor) facing stochastic demand not only sells its product, but also buys other product that it needs from the market. It either trades its unsold product for the product it needs on a barter platform or disposes of its unsold product at discounted prices at the end of the selling season like in the classical newsvendor model. We derive the retailer’s optimal order quantity, then analytically and numerically examine the impacts of barter on the retailer’s inventory decisions and profit. We find that barter exchange can help the retailer to manage demand uncertainty and improve profit. The optimal order quantity decreases with barter commission and barter uncertainty, while increases with demand uncertainty and the value of the product that the retailer needs. Barter is more advantageous with lower barter commission, larger demand uncertainty, lower barter uncertainty, and higher value of the product it needs.     

Optimal Pricing of Two Successive‐Generation Products with Trade‐in Options under Uncertainty

To entice consumers to purchase both current and next generation products, many manufacturers and retailers offer trade‐in programs that allow buyers of the first generation product to trade‐in the product and purchase the new generation product at a lower price. By considering the interactions between “forward‐looking” consumers and a firm when a trade‐in program is offered, we analyze a two‐period dynamic game to determine the optimal prices of two successive‐generation products in equilibrium, and examine the conditions under which trade‐in programs are beneficial to the firm. Our model incorporates market heterogeneity (valuation of the first generation product varies among the consumer population), product uncertainty (the incremental value of the new product is uncertain before its introduction), and consumers' forward‐looking behavior (consumers take future product valuation and prices into consideration when making purchasing decisions). With the trade‐in option, we show that consumers are willing to pay a price that is higher than their valuations of the current product. Furthermore, trade‐in programs are more beneficial to the firm when: (i) the durability of the current product is high; (ii) the market heterogeneity is low; or (iii) the uncertainty level (or the expected incremental value) of the new product is high. Finally, when the incremental value of the new product is more uncertain, consumers are more willing to purchase the current product because of the “option” value of the trade‐in programs and thus trade‐in programs can be more beneficial to the firm in this case.     

Limited Information and Advertising in the U.S. Personal Computer Industry

Traditional discrete‐choice models assume buyers are aware of all products for sale. In markets where products change rapidly, the full information assumption is untenable. I present a discrete‐choice model of limited consumer information, where advertising influences the set of products from which consumers choose to purchase. I apply the model to the U.S. personal computer market where top firms spend over $2 billion annually on advertising. I find estimated markups of 19% over production costs, where top firms advertise more than average and earn higher than average markups. High markups are explained to a large extent by informational asymmetries across consumers, where full information models predict markups of one‐fourth the magnitude. I find that estimated product demand curves are biased toward being too elastic under traditional models. I show how to use data on media exposure to improve estimated price elasticities in the absence of micro ad data.     

基于双向期权的供应链柔性契约模型

对需求不确定性大、生产提前期长、销售季节短的产品的供应链合作问题,建立了基于双向期权的单期两级供应链数量柔性契约模型,研究得出了销售商最优初始订货量和期权购买量,而且与单向看涨期权契约相比,销售商的期权购买量减小,初始订货量增加,但总的预期订货量减小.供应商的最优产量需综合考虑产品的正常生产模式和快速生产模式的成本,以及销售商执行期权的预期.供应商的生产不确定受销售商执行期权的相关性影响,降低相关性可以降低生产风险.双向期权契约能够提高销售商的采购柔性、降低市场风险,但也减少了部分收益.供应商增加了部分风险,同时也获得收益补偿.最后.通过数值算例分析了论文中的研究结论.     

Combined Pricing and Portfolio Option Procurement

In this paper, we study a single‐product periodic‐review inventory system that faces random and price‐dependent demand. The firm can purchase the product either from option contracts or from the spot market. Different option contracts are offered by a set of suppliers with a two‐part fee structure: a unit reservation cost and a unit exercising cost. The spot market price is random and its realization may affect the subsequent option contract prices. The firm decides the reservation quantity from each supplier and the product selling price at the beginning of each period and the number of options to exercise (inventory replenishment) at the end of the period to maximize the total expected profit over its planning horizon. We show that the optimal inventory replenishment policy is order‐up‐to type with a sequence of decreasing thresholds. We also investigate the optimal option‐reservation policy and the optimal pricing strategy. The optimal reservation quantities and selling price are shown to be both decreasing in the starting inventory level when demand function is additive. Building upon the analytical results, we conduct a numerical study to unveil additional managerial insights. Among other things, we quantify the values of the option contracts and dynamic pricing to the firm and show that they are more significant when the market demand becomes more volatile.     

Product Portfolio Strategies: The Case of Multifunction Products

Motivated by the proliferation of multifunction products, we investigate product portfolio decisions of a single firm by analyzing the impact of three major factors. First, because multifunction products provide complete or partial functionalities of single‐function products, we incorporate substitution or cannibalization effects between the potential products. Second, we explicitly model the variable costs of manufacturing the single‐function and multifunction products. Third, we examine the firm's pricing decisions because of their impact on the degree of cannibalization between the multifunction product and one or more single‐function products. Using an economic model, we first characterize the firm's optimal product portfolio (through a quantity‐based decision), which in turn determines the market equilibrium prices for each product in its portfolio. Some of the unique insights stemming from our analysis are: (a) the optimal product portfolio choice is driven primarily by maximum profit margins for the single‐function products weighted by the demand substitution effects; and (b) from a product design perspective, the complete functionality of the base single‐function product is always included in the optimal product offering, but this is not necessarily the case with the complete functionality of the nonbase single‐function product.     

Deferred life annuities: on the combined effects of stochastic mortality and interest rates

The paper analyzes the systematic risk which is inherent in a portfolio of deferred life annuities. We take into account stochastic mortality as well as stochastic interest rates. For the specification of the mortality rate dynamics, we consider a pure diffusion model as well as a compound Poisson jump model. The interest rate dynamics are given by a one-factor Hull–White model. All models, interest rate and mortality rate, are calibrated to financial market as well as demographic data. We use Monte Carlo simulations to approximate the variance of the discounted cash flow and its decomposition into a pooling and a non-pooling risk part. We also consider pricing effects using the principle of zero expected utility and the quantile principle. The estimated risk premiums are benchmarked to the equivalence premium. Finally, we focus on solvency requirements which are based on the investment decisions and the associated shortfall probability of the annuity provider.     

具有多元马氏需求的多产品多阶段库存优化模型

本文研究一类新的多产品库存控制策略,即具有多元马氏需求特征的多产品多阶段的订货点订货量(Q, R, SS)策略,该策略考虑市场需求在不同产品之间具有多元马氏转移特征,并考虑缺货因素设置安全库存。论文首先建立了多产品多阶段的多元马氏需求预测模型,并通过该模型确定了各种产品需求之间的关系。同时,在该模型的理论基础上,提出了多产品多阶段的总期望成本模型及其最优(Q, R, SS)策略,进而结合算例给出模型的最优策略的数值解。     

Drivers of private-label purchase behavior across quality tiers and product categories

Private labels hold a substantial share of consumers’ wallets and their popularity is still growing as they spread into various product categories and quality tiers. To determine the right branding strategy, in terms of offering uniform or different private-label brands across product categories, retailers have to know whether consumers use their private-label experience across product categories and private-label tiers. Therefore, we examine different determinants of consumers’ consideration sets. We apply proneness for certain private-label tiers, product categories purchased, purchase frequency, and variety seeking as internal determinants, which contribute to consumers’ knowledge and experience with private labels. Further, we use consumers’ price consciousness and promotion sensitivity as external determinants, which the retailer can use to influence consumers’ consideration sets in the short run. Our analyses are based on large-scale loyalty program data for a period of 24 months. In particular, we use the first 12 months to derive the determinants of consumers’ share of wallets regarding different private-label quality tiers in the second half of the sample. We conduct our analyses for 12 different product categories and aggregate the results by using meta-analytic techniques. Notably, some determinants show dissimilar effects across product categories (e.g., price consciousness and promotion sensitivity), while others (e.g., private-label proneness) are rather similar. We find that consumers’ general proneness for certain private-labels tiers leads to a propensity to purchase them in a specific category and in adjacent quality tiers. Further, we reveal that product category characteristics moderate the determinants of private-label share.     

Decision model for product rollover in manufacturing operations

The purpose of this study is to investigate critical decisions when planning for product rollover at a manufacturing company, and how to organise these decisions. A literature review and a case study are used to develop a decision model. The findings indicate that product rollover can be organised in a five-phase decision model. The research quality is strengthened by a structured literature review, but it can be argued that more empirical research is needed for validation. For researchers, this paper contributes with the identification of critical decisions and a model for product rollover. For practitioners, the study highlights the need to acknowledge the importance of product rollover and its role as a competitive weapon. In earlier studies, product rollover has mainly been investigated from a market perspective, so that this study contributes by investigating the issue from a manufacturing perspective.