This document summarizes a research paper that examines the relationship between purchase timing and brand switching for frequently purchased consumer products using scanner panel data. The study develops a model to analyze purchasing in two stages: timing of purchases and conditional probability of switching brands. It estimates the model for diaper and ketchup purchases. For diapers, higher income households buy more frequently while more educated households buy less frequently, and coupons rather than price influence switching. For ketchup, larger households buy more often and price negatively impacts switching. The study finds a significant positive correlation between longer purchase intervals and switching for ketchup but not diapers.
This document provides an introduction to dynamic demand modeling for storable and durable goods. It discusses how consumer stockpiling behavior and sales can lead to biases in static demand estimation. A simple demand model is then presented that accounts for demand anticipation effects using two consumer types - storers and non-storers. The model assumes perfect foresight, a fixed storage period, and derives different purchasing patterns between the four states of current and past price periods.
The document provides instructions for students taking the CBSE Board Examination for 2012-2013. It notes that students should write the code number on the answer booklet and serial numbers before attempting questions. It also allocates 15 minutes for students to read the paper before the exam starts at 10:15 AM. The paper contains questions in Economics with instructions for answering questions of different mark values and word limits for responses. It provides sample questions and answers regarding concepts in Economics like costs, demand, supply, utility, and perfect competition.
Deependra pal, amul ppt , factor analysis Deependra Pal
The document discusses a study analyzing consumer buying behavior for Amul Fresh Paneer in Pune, India. It conducted surveys in Pune and nearby areas to understand factors influencing purchasing decisions. A questionnaire was administered to 58 respondents to collect data on brand, price, demand, and other attributes. Factor analysis was performed to summarize the data into key factors driving consumer behavior. Three factors were identified relating to business aspects, pricing, and quality/packaging of paneer products.
- The document summarizes a lecture on using micro data with characteristics-based choice models. It discusses two key advantages of micro data: 1) It provides information on how observed individual characteristics interact with product characteristics. 2) It includes data on individuals who did not purchase products as well as second choices, giving insight into unobserved product characteristics.
- The model specifies utility as depending on observed and unobserved individual characteristics as well as product characteristics. Micro data on first choices matches individual characteristics to chosen products, while second choice data helps account for unobserved characteristics by holding individual conditions constant.
Bayesian Mixture Modeling of Structural Equation Modelsninohardt
1) The document proposes using Bayesian mixture modeling to account for heterogeneity in structural equation models (SEMs) by allowing for different data-generating mechanisms across observations.
2) It presents an example using a customer satisfaction survey where two competing theories imply different SEM structures.
3) The results show the mixture model fits the data better and estimates different path coefficients compared to a single-structure model, indicating some observations may come from an alternative generative process.
Avik Niyogi has over 7 years of experience in banking and financial services. He is currently serving as the Branch Manager of Odisha Gramya Bank in Cuttack, India. Prior to this, he worked as the Manager of Advances Department Head Office Credit Committee at Kaveri Grameena Bank in Mysuru, India. He also has experience working as a Consultant for Deloitte in Hyderabad, India and as an Analyst for Operational Risk at BlackRock in Gurgaon, India. He holds a PGDM in Marketing and Finance and is a CAIIB from the Indian Institute of Banking and Finance.
This letter from the Chairman and CEO of BlackRock encourages corporate leaders to focus on long-term value creation rather than short-term gains. It notes increasing pressure from activists and others for short-term results at the expense of long-term growth. The letter calls on companies to articulate their long-term strategies and resist pressures that undermine long-term value, and for governments and investors to adopt policies promoting long-termism.
This document provides an introduction to dynamic demand modeling for storable and durable goods. It discusses how consumer stockpiling behavior and sales can lead to biases in static demand estimation. A simple demand model is then presented that accounts for demand anticipation effects using two consumer types - storers and non-storers. The model assumes perfect foresight, a fixed storage period, and derives different purchasing patterns between the four states of current and past price periods.
The document provides instructions for students taking the CBSE Board Examination for 2012-2013. It notes that students should write the code number on the answer booklet and serial numbers before attempting questions. It also allocates 15 minutes for students to read the paper before the exam starts at 10:15 AM. The paper contains questions in Economics with instructions for answering questions of different mark values and word limits for responses. It provides sample questions and answers regarding concepts in Economics like costs, demand, supply, utility, and perfect competition.
Deependra pal, amul ppt , factor analysis Deependra Pal
The document discusses a study analyzing consumer buying behavior for Amul Fresh Paneer in Pune, India. It conducted surveys in Pune and nearby areas to understand factors influencing purchasing decisions. A questionnaire was administered to 58 respondents to collect data on brand, price, demand, and other attributes. Factor analysis was performed to summarize the data into key factors driving consumer behavior. Three factors were identified relating to business aspects, pricing, and quality/packaging of paneer products.
- The document summarizes a lecture on using micro data with characteristics-based choice models. It discusses two key advantages of micro data: 1) It provides information on how observed individual characteristics interact with product characteristics. 2) It includes data on individuals who did not purchase products as well as second choices, giving insight into unobserved product characteristics.
- The model specifies utility as depending on observed and unobserved individual characteristics as well as product characteristics. Micro data on first choices matches individual characteristics to chosen products, while second choice data helps account for unobserved characteristics by holding individual conditions constant.
Bayesian Mixture Modeling of Structural Equation Modelsninohardt
1) The document proposes using Bayesian mixture modeling to account for heterogeneity in structural equation models (SEMs) by allowing for different data-generating mechanisms across observations.
2) It presents an example using a customer satisfaction survey where two competing theories imply different SEM structures.
3) The results show the mixture model fits the data better and estimates different path coefficients compared to a single-structure model, indicating some observations may come from an alternative generative process.
Avik Niyogi has over 7 years of experience in banking and financial services. He is currently serving as the Branch Manager of Odisha Gramya Bank in Cuttack, India. Prior to this, he worked as the Manager of Advances Department Head Office Credit Committee at Kaveri Grameena Bank in Mysuru, India. He also has experience working as a Consultant for Deloitte in Hyderabad, India and as an Analyst for Operational Risk at BlackRock in Gurgaon, India. He holds a PGDM in Marketing and Finance and is a CAIIB from the Indian Institute of Banking and Finance.
This letter from the Chairman and CEO of BlackRock encourages corporate leaders to focus on long-term value creation rather than short-term gains. It notes increasing pressure from activists and others for short-term results at the expense of long-term growth. The letter calls on companies to articulate their long-term strategies and resist pressures that undermine long-term value, and for governments and investors to adopt policies promoting long-termism.
yoUtilBill - A Fresh Look At Residential Energy Efficiencystevemalloy
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2) Residential buildings account for 21% of US emissions, and efficiency upgrades could save over 28% of energy use. Upfront costs are $229 billion but would save $395 billion overall.
3) Individual homeowners have not made efficiency upgrades due to complex economics calculations and inability to recoup costs if moving. New financing options like property tax assessments may help overcome these barriers.
This document provides an agenda and overview of a presentation on sales and marketing for entrepreneurs. It discusses finding a micro-niche and developing the right mindset, message, and media. Examples are given of successful entrepreneurs like Mark Zuckerberg and tips are provided such as focusing on the customer's problems and benefits rather than the product. The presenter offers ongoing support to help entrepreneurs succeed through challenges of building a business.
This document summarizes a presentation given to small business owners on how to improve their sales and marketing. It provides tips on identifying a niche market, crafting clear messaging, using the right media and mindset for selling. Key points include finding a micro-niche that is unique, telling your story through a three-part message focused on benefits to customers, and exchanging value for contact details at meetups rather than just handing out business cards. The overall message is that small business owners have an awesome opportunity if they find the right niche and beliefs.
The document summarizes the goals, technical constraints, and solutions for rendering wounds in Left 4 Dead 2. It aimed to accurately locate wounds, match weapon strength by removing body parts, and allow multiple active wounds per model. Constraints included memory and CPU limits. The initial prototype used ellipsoids to cull pixels and fill holes with wound models, but had issues. The final solution combined ellipsoids with projected textures to create natural-looking wounds, blood effects, and up to 54 unique wounds per model with minimal performance impact.
El documento describe el método 5S, que consiste en 5 pasos para mantener el orden y la limpieza en el lugar de trabajo. Los pasos son: 1) Separar (separar lo necesario de lo innecesario), 2) Ordenar (organizar y almacenar lo necesario), 3) Limpiar (mantener el lugar de trabajo limpio), 4) Estandarizar (establecer procedimientos para el orden y la limpieza), y 5) Disciplina (mantener los hábitos de orden y limpieza).
Introduction to implementing social media at the expat archiveNavah Hochstein
The document discusses implementing social media at the Expatriate Archive Centre to raise awareness, publicize events and workshops, attract new volunteers and donors, and engage researchers. It recommends analyzing current contacts, finding new relevant audiences online and offline, building relationships through targeted content and ongoing dialogue. The plan involves continuing outreach, managing feedback daily, and monitoring impact through measurement to refine the strategy over multiple phases, with the goal of creating an interactive website to conclude the social media efforts.
El documento describe la metodología 5S para sistematizar y normalizar el lugar de trabajo. Consiste en 5 pasos: 1) sistematizar, 2) ordenar, 3) limpiar, 4) estandarizar y 5) disciplina. Se recomienda establecer controles visuales en 6 niveles para mantener los estándares y detectar desviaciones. El objetivo final es que el uso de controles visuales sea automático.
- Mobile gaming is a huge and rapidly growing market, with over 2 billion dollars in revenue in 2010 alone, over 50% of which comes from games.
- The hardware in phones and tablets is now comparable to last generation consoles and will surpass current gen consoles within 3 years, allowing for more advanced games.
- To develop for mobile, games need to be optimized for short play sessions, have simple one-finger controls, and be visually impressive while maintaining a low polycount and other optimizations to perform well on mobile devices.
Los sistemas de gestión son conjuntos de elementos relacionados que establecen la política y objetivos de una organización para lograrlos de forma planificada. Existen diversos sistemas de gestión como la calidad, medio ambiente, seguridad y salud laboral, responsabilidad social, recursos humanos, innovación e información, que pueden funcionar de forma paralela siguiendo estándares como ISO 9001, ISO 14001 y OHSAS 18001.
This document provides an overview of initial Big-IP configuration including hardware, licensing, file system, and basic network and management configuration. It also covers traffic processing concepts like pools, nodes, virtual servers and load balancing methods. Monitoring functionality and types of monitors like address, service, content and interactive are described. The document shows how to configure and assign different monitors to nodes, pool members and pools. It explains the status icons for monitor states like available, offline, unknown and unavailable.
http://inarocket.com
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The document discusses how personalization and dynamic content are becoming increasingly important on websites. It notes that 52% of marketers see content personalization as critical and 75% of consumers like it when brands personalize their content. However, personalization can create issues for search engine optimization as dynamic URLs and content are more difficult for search engines to index than static pages. The document provides tips for SEOs to help address these personalization and SEO challenges, such as using static URLs when possible and submitting accurate sitemaps.
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The document describes an industrial/applied math masters project that investigates optimal retirement portfolio allocation through Monte Carlo simulation. It models three investment options - cash/money market, stocks, and bonds - under various allocation schemes. The results show that balancing stability and growth is important, as portfolios with too much imbalance toward higher-risk/return investments performed poorer overall. Specifically, a 75% stock/10% bond/15% cash allocation yielded the highest success rate and average ending balance.
This document summarizes a lecture on analyzing demand systems for differentiated products. It discusses:
1) Demand systems provide information to analyze firm incentives and responses to policy changes. They are important for welfare analysis and constructing price indices.
2) Demand models can consider representative or heterogeneous agents, and model demand in product or characteristic space. Heterogeneous agent models in characteristic space are preferred as they allow combining different data sources.
3) Demand estimation requires simulating aggregate demand from individual demands, which provides unbiased estimates that can be made precise with large simulations.
yoUtilBill - A Fresh Look At Residential Energy Efficiencystevemalloy
1) Government agencies and homeowners have recognized the need to improve residential energy efficiency to reduce emissions. Sonoma County aims to cut emissions 25% by retrofitting 80% of homes and businesses.
2) Residential buildings account for 21% of US emissions, and efficiency upgrades could save over 28% of energy use. Upfront costs are $229 billion but would save $395 billion overall.
3) Individual homeowners have not made efficiency upgrades due to complex economics calculations and inability to recoup costs if moving. New financing options like property tax assessments may help overcome these barriers.
This document provides an agenda and overview of a presentation on sales and marketing for entrepreneurs. It discusses finding a micro-niche and developing the right mindset, message, and media. Examples are given of successful entrepreneurs like Mark Zuckerberg and tips are provided such as focusing on the customer's problems and benefits rather than the product. The presenter offers ongoing support to help entrepreneurs succeed through challenges of building a business.
This document summarizes a presentation given to small business owners on how to improve their sales and marketing. It provides tips on identifying a niche market, crafting clear messaging, using the right media and mindset for selling. Key points include finding a micro-niche that is unique, telling your story through a three-part message focused on benefits to customers, and exchanging value for contact details at meetups rather than just handing out business cards. The overall message is that small business owners have an awesome opportunity if they find the right niche and beliefs.
The document summarizes the goals, technical constraints, and solutions for rendering wounds in Left 4 Dead 2. It aimed to accurately locate wounds, match weapon strength by removing body parts, and allow multiple active wounds per model. Constraints included memory and CPU limits. The initial prototype used ellipsoids to cull pixels and fill holes with wound models, but had issues. The final solution combined ellipsoids with projected textures to create natural-looking wounds, blood effects, and up to 54 unique wounds per model with minimal performance impact.
El documento describe el método 5S, que consiste en 5 pasos para mantener el orden y la limpieza en el lugar de trabajo. Los pasos son: 1) Separar (separar lo necesario de lo innecesario), 2) Ordenar (organizar y almacenar lo necesario), 3) Limpiar (mantener el lugar de trabajo limpio), 4) Estandarizar (establecer procedimientos para el orden y la limpieza), y 5) Disciplina (mantener los hábitos de orden y limpieza).
Introduction to implementing social media at the expat archiveNavah Hochstein
The document discusses implementing social media at the Expatriate Archive Centre to raise awareness, publicize events and workshops, attract new volunteers and donors, and engage researchers. It recommends analyzing current contacts, finding new relevant audiences online and offline, building relationships through targeted content and ongoing dialogue. The plan involves continuing outreach, managing feedback daily, and monitoring impact through measurement to refine the strategy over multiple phases, with the goal of creating an interactive website to conclude the social media efforts.
El documento describe la metodología 5S para sistematizar y normalizar el lugar de trabajo. Consiste en 5 pasos: 1) sistematizar, 2) ordenar, 3) limpiar, 4) estandarizar y 5) disciplina. Se recomienda establecer controles visuales en 6 niveles para mantener los estándares y detectar desviaciones. El objetivo final es que el uso de controles visuales sea automático.
- Mobile gaming is a huge and rapidly growing market, with over 2 billion dollars in revenue in 2010 alone, over 50% of which comes from games.
- The hardware in phones and tablets is now comparable to last generation consoles and will surpass current gen consoles within 3 years, allowing for more advanced games.
- To develop for mobile, games need to be optimized for short play sessions, have simple one-finger controls, and be visually impressive while maintaining a low polycount and other optimizations to perform well on mobile devices.
Los sistemas de gestión son conjuntos de elementos relacionados que establecen la política y objetivos de una organización para lograrlos de forma planificada. Existen diversos sistemas de gestión como la calidad, medio ambiente, seguridad y salud laboral, responsabilidad social, recursos humanos, innovación e información, que pueden funcionar de forma paralela siguiendo estándares como ISO 9001, ISO 14001 y OHSAS 18001.
This document provides an overview of initial Big-IP configuration including hardware, licensing, file system, and basic network and management configuration. It also covers traffic processing concepts like pools, nodes, virtual servers and load balancing methods. Monitoring functionality and types of monitors like address, service, content and interactive are described. The document shows how to configure and assign different monitors to nodes, pool members and pools. It explains the status icons for monitor states like available, offline, unknown and unavailable.
http://inarocket.com
Learn BEM fundamentals as fast as possible. What is BEM (Block, element, modifier), BEM syntax, how it works with a real example, etc.
The document discusses how personalization and dynamic content are becoming increasingly important on websites. It notes that 52% of marketers see content personalization as critical and 75% of consumers like it when brands personalize their content. However, personalization can create issues for search engine optimization as dynamic URLs and content are more difficult for search engines to index than static pages. The document provides tips for SEOs to help address these personalization and SEO challenges, such as using static URLs when possible and submitting accurate sitemaps.
Lightning Talk #9: How UX and Data Storytelling Can Shape Policy by Mika Aldabaux singapore
How can we take UX and Data Storytelling out of the tech context and use them to change the way government behaves?
Showcasing the truth is the highest goal of data storytelling. Because the design of a chart can affect the interpretation of data in a major way, one must wield visual tools with care and deliberation. Using quantitative facts to evoke an emotional response is best achieved with the combination of UX and data storytelling.
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The document describes an industrial/applied math masters project that investigates optimal retirement portfolio allocation through Monte Carlo simulation. It models three investment options - cash/money market, stocks, and bonds - under various allocation schemes. The results show that balancing stability and growth is important, as portfolios with too much imbalance toward higher-risk/return investments performed poorer overall. Specifically, a 75% stock/10% bond/15% cash allocation yielded the highest success rate and average ending balance.
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2) Demand models can consider representative or heterogeneous agents, and model demand in product or characteristic space. Heterogeneous agent models in characteristic space are preferred as they allow combining different data sources.
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1. Joint estimates of purchase timing and brand switch tendency: results from a scanner panel
data set of frequently purchased products
F. F. Gönül, P. T. L. Popkowski Leszczyc, and T. Sugawara
Carnegie Mellon University, University of Alberta, and
Carnegie Mellon University
ABSTRACT. In the marketing literature, purchase timing and brand choice behavior of households have
generally been treated independently. The subsumed independence of the two events can be restrictive. In
this paper we relax and test the independence assumption. We study purchase behavior in two stages: In
the first stage we model the timing of purchases. The second stage focuses on the conditional probability of
switching given that a purchase took place. We use longitudinal data on household purchases for two
different product categories; diapers and ketchup. The joint formulation exploits the information in the
scanner panel data more fully than has been possible before.
I. INTRODUCTION
Our purpose in this paper is to measure the correlation between purchase timing and brand switch behavior
of households. More specifically, we want to study (i) whether households switch brands more often for
the products they purchase more frequently or for the products they purchase less frequently. (ii) We want
to identify the demographic variables that influence purchase timing; and to identify the marketing variables
that influence the brand switching decisions. These research issues are of utmost importance to brand
managers of consumer products who are interested in encouraging purchase acceleration and loyalty to their
brand. Managers can implement our model in identifying market segments that buy more often but switch
less often, the heavy users of a brand or segments with growth potential.
Our data is from the scanner panel purchase data collected in two cities by the A.C. Nielsen Company for
a period of approximately one year. We aggregate the purchases to weekly units and select two categories.
We test our model and find that while for purchases of diapers there is no evidence of a significant
correlation between purchase timing and brand switching, for ketchup purchases, there is a significant
positive relationship between the timing of purchases and brand switching.
II. ECONOMETRIC MODEL
The likelihood function for a purchase occasion i that constitutes a switch from the previous purchase that
2. took place t periods ago is,
Li = Pr(j → k,t)
= Pr(j → k t) ⋅ f(t)
where j denotes the origin brand, k denotes the destination brand, and t stands for the interpurchase time.
Conversely, the likelihood function for a repeat purchase occasion i (a nonswitch event) after t periods is
given by, Li = (1-Pr (j → k t)) • f(t). We assume the switch from j to k is a discrete choice governed by a
random utility model. That is,
Ujk = _jk + ujk,
where ujk is normally distributed ( u jk _ N(0, σ u 2)). 1 We assume brand switching imposess switching
costs and hence we assume different utilities for switching and staying with the same brand. A switch
occurs if the utility of switching is greater than the utility of not swtching. (We arbitrarily normalize the
utility of not switching to zero). We further assume that the interpurchase time (t) is lognormal, and is
correlated with the random utility component. Then Li has a closed-form expression given by a bivariate
normal. More explicitly,
Pr(j → k) = Pr(_jk + ujk > 0), and
Pr(j → k t) = Pr(_jk + ujk > 0 ln(t)) J,
where J is the Jacobian of the transformation from t to ln(t). Then, the likelihood for a switch occasion
is,
Li = Pr(_jk + ujk > 0 ln(t)) J f(t).
Since the conditional distribution, g(ujk ln(t)), is a normal distribution, the likelihood function is the
product of two normal distributions and is easy to evaluate. Specifically,
σ u (ln(t) - ))] 1 _ φ ( ln(t) - µ t )
Li = [1 - Φ(- _ jk - ρ µt 2
σt ln(t) σ t σt
2
where ln( t) _ N( µ t , σ ), φ ( _ ) 3 stands for the standard normal p . d . f ., Φ (•) 4 denotes the standard
t
normal c.d.f., and the correlation coefficient, ρ = Corr(ujk, ln(t)), measures the correlation between purchase
3. timing and the probability of a switch. A positive correlation indicates that when interpurchase time
2
increases the likelihood of a switch increases. We impose the restriction that σ (1 - ρ ) = 1 5 in order to
2
u
identify the bivariate normal model.
III. ESTIMATION
We estimate our model on two data sets, with diaper purchases and ketchup purchases. The diaper data
consists of 152 households who regularly bought diapers from among 3 national brands during the course
of a year. There are a total of 2675 purchases. The ketchup data consists of 200 households who regularly
bought ketchup from among 2 national brands and store brands (combined as one brand, since the purchase
data is across stores) over the course of one year. There are a total of 1567 ketchup purchases. The average
interpurchase time for disposable diapers is about 2 weeks, and for ketchup about 10 weeks. Our findings
are presented in Table 1.
--Insert Tabel 1 here--
Diapers
Households that have higher incomes are likely to buy diapers more frequently, ceteris paribus, and
households that are better educated are likely to buy diapers less frequently, ceteris paribus. Coupons rather
than price are the determining factor in influencing brand switches in the diaper market. There is no
significant correlation between interpurchase time and the propensity to switch.
Ketchup
Households that are larger in size are likely to buy ketchup more often, ceteris paribus. The remaining
demographic variables have no influence on purchase timing. Price, significantly and negatively influences
the probability of a switch. In-store displays do not play a role in encouraging consumers to switch brands.
The correlation coefficient is positive and significant. Households that buy less often may "forget" the
brand and tend to switch more often than other households.
4. IV. CONCLUSION
Our empirical analysis shows that it is possible to identify the characteristics of households that buy a
certain product more often than others. This facilitates target marketing and enables managers to better
target advertising and promotional campaigns to different consumer segments. For example, a managerial
policy could be to target reminder advertising to heavy users and target price incentives to switchers. We
also show that brand switching is caused by different characteristics depending on the product category.
For diapers, price is not a significant factor but coupon is. In a category like ketchup, where coupons are
negligible, store display does not induce households to switch, while price does.
Different from the prior literature, in this work, we measure the correlation between the timing of
purchases and brand switches. We find that when the purchase interval gets longer, consumers are more
likely to switch. Hence, frequent purchasers are more likely to be brand loyal. For ketchup purchases we
observed a significant correlation between interpurchase time and the propensity to switch. Thus, we are
led to conclude that if the product is essential and bought regularly like diapers, loyalty may continue.
However, if the product is not essential like ketchup, where there are many substitutes, then switching may
be more prevalent. These results are consistent with findings in the promotional literature. Price
promotions, reflected in the price of ketchup, tend to lead to purchase acceleration, while coupons (mostly
used for diaper purchases) generally do not lead to purchase acceleration.
5. _____________________________________________________________________________________
Table 1
Results of Analysis of Purchase Timing and Brand Switching
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DIAPER KETCHUP
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Interpurchase Time
Constant 0.5941** 1.7766**
(0.0704) (0.1179)
Education 0.0316** 0.0135
(0.0092) (0.0130)
Income -0.0172** 0.0016
(0.0058) (0.0089)
Household Size ---- -0.0808**
(0.0173)
Switch Propensity
Constant -0.9121** 0.1074
(0.3360) (0.2579)
Price -0.0131 -0.3526**
(0.0230) (0.0661)
Coupon 0.4387** ----
(0.0584)
Display ---- -0.1427
(0.0960)
Correlation between 0.0251 0.0871*
Interpurchase Time and Switch (0.0278) (0.0440)
Propensity
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Notes: Standard errors are in parentheses. Significance at 1% is denoted by (**) and at 5% by (*).
Household size is not included in the diaper model, since there is not much variation in size
among the purchasing households. Coupon is not included in the ketchup model, since coupon
activity is negligible in the category. Likewise, display activity is virtually nonexistent in the
diaper category. We exclude these variables without loss of significant information.
5