The influence of supermarkets layout on healthy eating

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The influence of supermarkets layout on

healthy eating

What is the effect of encountering healthy food early versus late in a shopping

trip on the healthiness of the shopping cart? How does this effect change when a

customer is impulsive?

January 14, 2019

Lieke Oost

Studentnumber: s2333791 E-mail: l.oost.2@student.rug.nl

Master Marketing Management – University of Groningen Faculty of Economics and Business

Supervisor: M. T. van der Heide

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Abstract

Obesity is a growing problem in todays’ society. People are getting fatter because of eating too much easy available and high-caloric food. Supermarkets can influence the customers in the products they buy during their shopping trip. One of the aspects which can unconsciously influence the customer is the layout of the supermarket. When in a shopping trip does the customer get confronted with the different product categories? Earlier decisions made may influence the decision a customer is currently making, or will make in the future. The personality of the customer may as well influence their decisions in the supermarket. More impulsive customers tend to buy more unhealthy products than the customers who are less impulsive. In this study the goal is to understand how the layout of a supermarket

influences the healthiness of the shopping cart of the customer. The research question used is:

What is the effect of encountering healthy food early versus late in a shopping trip on the healthiness of the shopping cart? How does this effect change when a customer is impulsive?

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1. Introduction

Obesity is becoming a bigger problem in todays’ world. Associated illnesses such as cancer, heart disease and diabetes have caused the raising interest in finding ways to

encourage consumers to make healthier food choices. People want easy access to a variety of tasty, convenient, inexpensive, and safe foods that can be eaten in large quantities. By

fulfilling these needs food marketers have been accused of contributing to the growing problem of global obesity (Brownell and Battle Horgen, 2003; Kessler, 2009; Popkin, 2009; Swinburn et al., 2011; Nestle and Nesheim, 2012).

Many of our food choices are made in the supermarket, some of the choices are already planned, but up to 60% of the food choices are unplanned and made in the supermarket itself (Inman, Winer and Ferraro, 2009). Supermarkets are constantly changing and evolving. In industrialized countries, their power in the food system is unprecedented (Vorley, 2003). Supermarkets are becoming important gatekeepers of the food supply, and as diet-related diseases and associated risk factors (heart disease, some cancers, obesity) become an ever-increasing burden on global scale (World Health Organization, 2005). In developing countries, it has been suggested that the growth of supermarkets – and the processed foods they sell – is a driver of the ‘nutrition transition’ to diets high in high-calorie, nutrient-poor foods (Popkin, 2006). The development of supermarkets has been, and still is, in part a response to changes in the habits, demands and preferences of consumers, but it has also affected the decisions the consumers make about food (Clarke, 2000). Supermarkets are, in the words of Dawson (1995), ‘both reactive and proactive agents in the process of consumer choice’.

In most supermarkets, fruit and vegetables are placed in the beginning, although it may not seem very logical to start your shopping trip with vulnerable products like fruit and vegetables. Thinking about this, it may seem compelling that after putting these healthy products in your basket, consumers feel less guilty when buying more unhealthy products later in their shopping trip. Few studies already show whether buying more unhealthy foods when first being confronted with the healthy option is true. The phenomenon of licensing can explain why this might be the case. Earlier research state that people are more likely to choose unhealthy foods when the decision context allows them to justify the consumption (Khan and Dhar, 2006; Kivetz and Simonson, 2002; Kivetz and Zheng, 2006).

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that is related to overeating and obesity is impulsivity (Davis, Levitan, Smith, Tweed and Curtis,.2006; Guerrieri et al, 2007; Nederkoorn, Braet, van Eijs, Tanghe and Jansen, 2006). Impulsivity is defined as the tendency to think, control and plan insufficiently (Solanto et al, 2001). Impulsive customers seem to be easier depleted by the subsequent decisions which need to be made in a supermarket, so the location of the fruit and vegetables will influence how “fresh” they are in their shopping trip and therefore can influence the decisions they make (Baumeister, 2002).

The layout of the supermarket, or more generally, the order in which the consumer is confronted with the different products or product categories, is interesting because it can influence a lot of different things. It may affect the number of products purchased or the different product categories a customer will see during its shopping trip and, what will be examined in this study, the healthiness of the products purchased. Currently there is not a lot literature available about the layout of a supermarket. This might be because it differs over countries and continents. Some research has been done to the layout of supermarkets but these articles are more aimed at the layout in terms of the location of the aisles, rather than the order in which the product categories are presented (Larson, Bradlow and Fader, 2005; Page, Trinh and Bogomolova, 2019).

Combining all these elements, in this paper the main research question will be:

Encountering healthy food early in the shopping trip means for supermarkets that the fruit and vegetables are located close to the entrance and late means that they are located close to the check-out.

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Kervenoal, Perez-del-Aguila, and Kirkup, 2004). The layout for supermarkets differ and only few studies have investigated what the impact of this layout within the store is on the

healthiness of the shopping cart of consumers. Also, since impulsivity of the customer plays an important role in the supermarket, for on one hand the customer itself because they may be spending more money or buying more unhealthy food than intended, and on the other hand the direction of the supermarkets, because they can find ways to plan their layout so that customers buy healthier food.

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2. Theoretical background

Every day people have to make lots of choices, some more simple than others, some are made without thinking and others are taking longer to considerate. The environment around us influences the choices we make, and also choices often don’t stand on itself, choices we made or make in the past or future can influence our current choices. The supermarket is a place where a lot of choices need to be made, choices about, brands, products or even aisles taken. The choice about which aisle a customer takes, or which route through the supermarket they take can influence the choice in products they make. Our shopping behaviour is

influenced by multiple factors including the layout of the store. In the supermarket past decisions can also influence the current and future decisions a customer makes. This is one of the reasons why the layout is important for a supermarket. They can influence the customers in the healthy or unhealthy food choices they make.

2.1 Layout of supermarket

In the Netherlands, most supermarkets have the same layout, this can be seen in images 1 and 2. Albert Heijn and Jumbo are the two biggest supermarket retailers in the Netherlands. Their layout look alike in terms of, the fruit, vegetables and meat are at the beginning, dairy is located at the furthest point of the supermarket and bread is situated at the side. Because of placing all the daily needed products at the end/sides, consumers need to go through the whole store in order to get what they want, this way it is more likely that they buy something which they were not intended to buy. Layouts are not only useful for improved

utilization of buildings and land, but are very

much concerned with increasing sales (Cil, 2012). In a survey conducted by Punjaisri and Wilson (2007) it was found that layout has a big influence on customers and that customers want the stores to spend whatever it takes to create a layout that minimizes wasted steps and motion in the shopping process.

Also one of the biggest evolvements around supermarkets these days is the movement towards online shopping they are making. Customers can shop on the websites of the

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supermarket and can choose to pick up their groceries in the store, or let them be delivered to their house. Also online the customers are making decisions and are following a certain ‘path’ through the online shopping environment. This paper is focused on supermarkets in general, but also the online

developments are somehow taken into

account, because the main study of this research will be conducted online. 2.2 Decision making

A supermarket is a place of sensory stimuli. Consumers are confronted with colourful product displays of fruit and flowers, perfectly aligned packages of snacks on end-cap

displays, and even advertisements covering the floor (Inman et al, 2009). These in-store stimuli are sometimes used by customers as cues to remind them what they need, but they can also lead to unplanned purchases, which are particularly the case for impulsive customers. The layout of the supermarket can involve the products the customers buy, this is because it can affect the number of aisles a customer shopped. As customers shop the store more completely, they become exposed to a greater number of product categories and in-store displays, which can influence their decisions (Inman et al. 2009).

The decisions made in a supermarket by a consumer are mostly more than one single decision. They make a series of decisions in which one choice follows another. Which vegetables are we going to eat tonight? What brand of cereal do I want? Recent work from, for example, Dhar and Simonson (1999) about the effect of prior decisions on subsequent choice show that the choice of the first item influences how people combine subsequent items in a consumption sequence to attain a peak experience on a focal goal (e.g., health, pleasure). 2.3 Supermarkets and obesity

Decision making in the supermarket and the unplanned purchases associated with it can cause the customer to buy more unhealthy food than planned. The article of Hawkes (2008) and the article of Chandon and Wansink (2012) both discuss what the dietary implications are for price, place, product and promotion marketing. The article of Hawkes (2008) found that decisions made by supermarket operators have consequences for the diets of

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consumers around the world. Food marketers are not focused on making people fat, but on making money. Because of the free market, food companies that are less profitable than their competitors are likely to end up being acquired by their rivals to go bankrupt (Chandon and Wansink, 2012). Despite this competition supermarkets already engage in some nutrition-related activities, like developing healthy own-brand foods and reducing fat, sugar and salt in their own brand products. Still the question arises if this really helps the consumer.

Supermarket operators are certainly in a powerful position of having the potential to

encourage healthier diets and on a large scale, but to drive this change it will take more than nutrition-related activities that still largely rely on consumer decisions (Hawkes, 2008). 2.4 Licensing

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2.5 Primacy effect

Another theory which could help understand how customers are making decisions is the primacy effect. When people are presented a list of items they are more likely to recall the items at the beginning than items which are in the middle of the list. Such phenomena are called the primacy effect. (Stewart, Stewart, Tyson, Vinci and Fioti, 2004).

Researchers have developed several theories to explain primacy effects. One of these well-known theories is the modal model of Atkinson and Shiffrin (1968). Although, the model was criticized and challenged by other researchers, because they think other models can explain a wider scope of memory findings, but these other models cannot account for the full set of findings used to support the modal model. So, the modal model is still one of the most influential works in the literature of verbal learning and memory (Healy and McNamara, 1996).

Atkinson and Shiffrin proposed three distinct memory stores: sensory registers, short-term store (secondary memory), and long-short-term store (secondary memory). The study stated that the primacy effect was more related to the long-term store. The study of Atkinson and Shiffrin (1968) stated that each item in a list entered into a fixed-capacity rehearsal buffer and displaced a randomly selected item already there when the capacity (about four items) had been exceeded. When an item was in the short-term buffer, its information may be transferred to the long-term store. When they asked people to free recall the items, they recalled those items still remaining in the short-term buffer and then made a fixed number of searches in the long-term memory stored. Based on this idea, items at the beginning of a list receive more rehearsals than items in the middle or the end of the list. Therefore, these items are more likely to be transferred to and retained in the long-term store, which is observed as the primacy effect.

In the case of healthy grocery shopping in a supermarket, the primacy effect will affect the way consumers look at what is already in their shopping cart. Consumers will be more likely to recall the items they bought at the end or beginning of their shopping trip. Based on the idea of items at the beginning of the supermarket receive more rehearsals and combining this with licensing theory earlier discussed, the shopping cart is expected to be healthier when fruit and vegetables are encountered early in the shopping trip. The items early in the

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and vegetables a customer already has in their basket will boost the self-concept of the customer, reduces the negative associations with buying more unhealthy food after that. 2.6 Impulsivity of a customer

The healthiness of the choices made is influenced by different factors, among one of them is the impulsivity of the customer. To decide for an impulsive purchase, the customer must see some useful or tasty food which is not contained in the purchase plan. This means that the quantity of impulse purchases is correlated to the length of the path of the customer in the shop (Boros, Feher, Lakner, Niroomand and Vizvari, 2016). Each customer goes to the supermarket with a more or less well-defined purchase plan. Often, customers also buy items which are not on their purchase plan, these are called impulse purchases (Underhill, 1999). Actually most of the purchases a customer makes are unplanned, for example Inman et al. (2009) estimate that 60,9% of purchases are unplanned.

Psychologists and consumer researchers believe that individuals vary in their proclivity to act impulsively (Beatty and Ferell, 1998; Puri, 1996; Rook, 1987; Rook and Fischer, 1995; Rook and Gardner, 1993; Weun, Jones and Beatty, 1998). For example, Rook and Fisher (1995) argue that “our belief is that individuals’ impulse buying tendencies can be conceptualized as a consumer trait”. In addition, Rook (1987) states that, “People vary in their impulse buying proclivities. It is useful to think of consumer impulsivity as a lifestyle trait.” Impulse buying tendency can be defined as: “The degree to which an individual is likely to make unintended, immediate, and unreflective purchases (i.e., impulse purchases) (Jones, Reynolds, Weun and Beatty, 2003).”

The study of Nederkoorn, Guerrieri, Havermans, Roefs and Jansen (2009) found that consumers who were both hungrier and more impulsive bought more calories. The higher amount of calories bought can be attributed to particularly the purchase of high caloric snack foods. Hungry impulsive consumers are especially vulnerable to buying snack calories. The effect of being impulsive or hungry on the number of unhealthy products a customer buys is likely to be influenced by the placement of the fruit and vegetables.

2.7 Self-control

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buy the product (Baumeister, 2002). The paper of Hoch and Lowenstein (1991) stated that the outcome of such consumer decision points depends considerably on the conflict between the competing strengths of self-control and desire.

The causes of self-control failure are important for understanding impulse buying and similar aspects of consumer behaviour (Baumeister, 2002). Studies of Baumeister,

Heatherton, Tice and Marsh (1996) and Muraven, Tice and Baumeister (1998) found that performing any act of self-control seems to deplete some crucial resource within the self, and that resource is then no longer available to help the person on the subsequent self-control task. Research of Twenge, Baumeister, Tice and Schmeichel (2001) found that making choices and decisions appears to reduce the same resource as is used for self-control. This is especially relevant for consumer behaviour, as consumers often must make multiple decisions and may also be coming from a context (such as a job) in which decisions are required.

When going to the supermarket customers have to make multiple decisions. If each decision along the way depletes the resource slightly, then people should show a tendency to become more impulsive and less self-controlled towards the end of a series (Baumeister, 2002). This theory expects that impulsive customers will show their impulses late in a shopping trip. Thus, encountering fruit and vegetables late in the shopping trip will influence the healthiness of the shopping cart of impulsive customers in a positive way. When fruit and vegetables are placed late in the shopping trip when customers are low in self-control they are more likely to buy unplanned healthy products instead of high caloric snacks.

2.8 Conceptual model and hypotheses

Given the current literature which is present about supermarkets influencing the (healthy) food choices of their customers the following conceptual model is established.

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Given the literature about decision making in the supermarket, it is expected that the placement of the fruit and vegetables will influence the healthiness of the shopping cart. The shopping route will differ when fruit and vegetables are in a different place in the store, which can make them buy more or different products. The literature about licensing states that after intending to be virtuous, the concept of people is boosted, this reduces negative self-attributions which are associated with the purchase of relative luxuries. When fruit and vegetables are at the beginning, customers boost their self-concept by putting it in their shopping cart, after this they feel less guilty about buying unhealthy food.

When the fruit and vegetables are placed at the end of a supermarket, customers first have to go the entire store to buy their healthy food. The primacy effect states that customers are more likely to remember items they bought in the beginning of the trip. When the healthy food is at the end, the first items they will put in their cart are more likely to be unhealthy. Keeping in mind that they already bought unhealthy items in the beginning can positively affect the healthiness of their entire shopping cart. On the other hand, following the same logic of the licensing theory, the article of Hui, Braclow and Fader (2009) argues that first buying a vice category (unhealthy product), reduces the consumer’s self-concept and increases the negative self-attribution associated with additional purchases from vice categories (more unhealthy food).

The first hypothesis following the conceptual model is:

H1: When consumers are confronted with the fruit and vegetables late in their shopping trip their shopping basket will be healthier than when they are confronted with it earlier in their shopping trip.

Recent research already stated that hungry and impulsive customers are more vulnerable to buying high caloric snacks (Nederkoorn, Guerrieri, Havermans, Roefs and Jansen, 2009). When a customer is impulsive its self-control while doing groceries is lower than for the customers who are less impulsive. This lower self-control is likely to make them buy more unhealthy food.

The second hypothesis, to test the effect of the moderator on the independent variable is:

H2: When a consumer is impulsive they are more likely to buy unhealthy food.

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earlier decisions already depleted their capacity. Thus, having the fruit and vegetables located at the end of the supermarket will positively affect the healthiness of the shopping cart. The third hypothesis:

H3: The impulsivity of a customer will strengthen the relationship between the late

confrontation with fruit and vegetables in a shopping trip on the healthiness of the shopping cart.

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3. Method

3.1 Experiment

Most research conducted about the effects of layout involve laboratory research. Not using in-store data can affect the external validity, however in-store approaches may affect the privacy of the customer. To preserve external validity and the privacy of customers, an

experimental design based on a supermarket environment seemed the most appropriate (Smith and Burns, 1996).

An experiment was used to identify the effects of fruit and vegetables placement on the healthiness of a shopping cart and whether the impulsivity of a person influences this. The experiment followed a between-subjects design in which the participants were randomly assigned to either a condition in which the fruit and

vegetables were encountered early in the shopping trip, or a condition in which the fruit and vegetables were encountered late in the shopping trip. The participants in this survey consisted for 28.8% of men and 71.2% of women. The average age of the participants was 36.97, the youngest participant was 17 and the oldest 73 years old. The survey was online and in English. In the survey the goal of the research was only told at the end, because telling it in the beginning might have affected the

decisions made later in the survey by the participant. The instructions stated that the researcher is only interested in their opinion and that there are no right or wrong answers. After that the participant was given some information about the shopping trip which

followed. The information told them that they needed to do groceries for two days, including breakfast, lunch, dinner, snacks and drinks. They had to choose the products they would normally choose when doing groceries, or choose the closest available option. The whole experiment can be found in Appendix B.

The 125 participants were randomly assigned to two conditions (fruit and vegetables early versus late in the shopping trip), the other product categories (meat/vegetarian

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substitutes, base of the meal, bread/crackers, salty snacks, drinks, dairy, frozen products and sweet snack) were shown in a random order before or after the fruit and vegetables. 64 participants saw the fruit and vegetables early in their shopping trip and 61 participants saw them late in their shopping trip. For a visualization of how the experiment with the fruit and vegetables early in the shopping trip looked like see image 3. After the shopping trip a control question was asked to check whether the participant was paying attention, the question was if they saw the fruit and vegetables in the beginning or at the end of their shopping trip.

3.2 Measures

Rook and Fisher’s (1995) nine-item scale was used to measure general buying tendency (impulse buying as a personality trait), see image 4. The questions will be answered using a 7-point Likert scale, where 1= strongly disagree and 7= strongly agree.

The dependent variable, healthiness of the shopping cart was defined according to the number of calories in a product. The number of calories per

product per 100 grams was used (see appendix A). The number of calories per 100 gram for some products can be high even if these products are considered healthy options. For this reason the products were also put into three categories: healthy, unhealthy and other (see appendix A). These categories were made up according to the ‘Schijf van Vijf’ from the

Voedingscentrum. The ‘Schijf van Vijf’ is an information model about healthy eating which is

supported by reliable scientific information available at the moment. De ‘Schijf van Vijf’ sketches the framework for a healthy diet for the entire Dutch population (Feskens, 2016) . They advise eating enough fruit and vegetables, unsaturated fats, fish, meat, eggs, legumes, unsalted nuts and dairy. Also whole grain bread and other grain products and potatoes are part of a healthy diet. For drinks they advise black or green tea and water. Products they advise not to eat too much are: white bread or pasta, salted nuts, drinks with a lot of sugar, snacks like cake and sweets (Feskens, 2016).

Some questions about the health consciousness of the participants were asked after the shopping trip, these questions are used as a control variable. Health consciousness will likely affect the healthiness of the shopping cart, since health consciousness people are taking care of their diet and health.

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4. Results

The online experiment has been filled out by 125 participants. Of those 125 participants around 30% was male and 70% female. 7 participants indicated to eat vegetarian or vegan, 18 participants had other dietary restrictions, like for example no gluten, no cow milk or diabetes. Around 10% of the participants is currently following a diet to lose weight. On a 7-point Likert scale the participants ranked a mean of 3.55 with a standard deviation of 1.160 on the impulsivity items.

4.1 Reliability

Before analysing, the impulsivity items needed factor analysis. Factor analysis was used to bring intercorrelated variables together under more general, underlying variables. One of the questions about impulsivity (I carefully plan most of my purchases) was reverse-coded so that it measures the same way as the other questions. The result of the KMO measure of sampling adequacy was 0.873 which is sufficient to continue with the factor analysis, also Bartlett’s Test of sphericity was significant (0.000) and the communalities of the nine items were all above 0.4. All nine items could be put together into one variable, the loadings of each item on the variable is higher than 0.5.

After that the variables were tested on their reliability using the Cronbach’s alpha. As can be seen in table one the Cronbach’s alpha of the nine items is 0.881, which means that the variables have a high internal consistency.

Table 1

Reliability analysis for impulse buying tendency and health consciousness

Cronbach’s alpha Cronbach’s Alpha Number of items

Impulsivity 0.881 9

Health consciousness 0.832 6

All nine items of the impulsivity scale could be transformed into one variable which indicates the level of impulsivity of a participant.

For the items of the control variable health consciousness factor analysis was used as well. The result of the KMO measure of sampling adequacy was 0.828, sufficient to continue with the factor analysis, also Bartlett’s Test of sphericity was significant (0.000). The

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variable and the loadings of each item on the variable is higher than 0.5. The reliability is testes using the Cronbach’s alpha, which can be seen in table one.

4.2 Hypothesis testing The first hypothesis:

H1: When consumers are confronted with the fruit and vegetables late in their shopping trip their shopping basket will be healthier than when they are confronted with it earlier in their shopping trip.

is tested using an independent sample t-test. In this analysis the healthiness of the shopping cart (measured in calories) is the dependent variable and the placement of the fruit and vegetables is the independent variable. Levene’s test was significant (0.049), which means equal variances cannot be assumed. The results of the t-test indicated that people who saw the fruits and vegetables at the end of their shopping trip purchased more calories in their total shopping trip than people who saw it at the beginning, t(123) = -3.270, p=0.001 (Appendix C, table 1)

Another t-test was done to find out if the average number of calories per product purchased was different for people who saw the fruit and vegetables in the beginning or at the end. The average calories per product is calculated by dividing the total number of calories purchased by the total number of products a participant chose. In this analysis the independent and dependent variable stay the same, but the dependent variable (healthiness of shopping cart) is now measured as the average number of calories per product purchased. Levene’s test was not significant (0.693), which means that equal variances can be assumed. The results of the t-test indicated that, as well as in the first t-test, people who saw the fruits and vegetables at the end of their shopping trip purchased higher caloric products than people who saw it at the beginning, t(122.89)= -2.624, p=0.010 (Appendix C, table 2). There was no significant difference between the number of products customers purchased for early versus late confrontation with fruit and vegetables t(123)=-1.642, p=0.103. Also no significance difference in the impulsivity level of the customers in the two different conditions could be found t(123)=-0.674, p=0.501.

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leftover category. Customers who encountered the fruit and vegetables early in the shopping trip choose 26.61% unhealthy options relative to the total number of products they choose. The customers who encountered the fruit and vegetables late in their shopping trip chose 29.89% unhealthy options relative to the total number of products they choose. Putting the products in categories gives the same outcome as when the number of calories per product per 100 grams are used.

In table two the average numbers for early versus late confrontation with the fruit and vegetables are stated.

Table 2

Average numbers for customers confronted early vs. late with the healthy food

Number of calories total Average calories per product Number of products Average level of impulsivity of participants Percentage of unhealthy food chosen from the total Early 2909.52 195.14 15.20 3.48 26.61% Late 3536.33 214.01 16.75 3.62 29.89%

For the second hypothesis:

H2: When a consumer is impulsive they are more likely to buy unhealthy food.

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Figure 1: Calories purchased relative to customers' impulsivity

The third hypothesis:

H3: The impulsivity of a customer will strengthen the relationship between the late

confrontation with fruit and vegetables in a shopping trip on the healthiness of the shopping cart.

To test whether impulsivity of a customer moderates the effect of the placement of fruit and vegetables (early vs. late) on the healthiness of the shopping cart (in calories), an linear regression was conducted. In this analysis the early or late position of the fruit and vegetables is the independent variable, healthiness of the shopping cart in calories is the dependent variable and the impulsivity of the customer is the moderator.

First, is the model without the interaction of the placement of fruit and vegetables and impulsivity of the customer significant? Yes it is, F(2,122)=6.234, p=0.003. Now it is

interesting to see if the model with the interaction of the independent variable and the

moderator is significant. This model is significant as well, F(3,121) =4.284, p=0.007, but this model did not account for significantly more variance than solely the impulsivity of the

customer and the placement of the fruit and vegetables themselves, Rchange =0.003, p=0.508. In the model without the interaction, both impulsivity F(2,122)=2.312, p=0.022 and the early versus late confrontation F(2,122)=2.523, p=0.013 are significant. In the model with the interaction, impulsivity is on the border of significance F(3,121)=2.050, p=0.043, but the early versus late confrontation is not significant, F(3,121)=1.409, p=0.161 (Appendix C, table 4). So, adding the interaction variable to the regression weakens the effect of both the

independent variable and the moderator on the dependent variable. So, the impulsivity of the 0 500 1000 1500 2000 2500 3000 3500 4000 0 50 100 150 200 250 1 2 3 4 5 6 7 T o tal ca lo ries C alo ries p er p ro d u ct Level of impulsivity

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customer does not moderate the effect of placement of the fruit and vegetables on the healthiness of the shopping cart.

Finally, the control variable health consciousness is added to the regression to test if this variable significantly influences the shopping cart, and to see if it affects the other independent variables. The regression for health consciousness was not significant, F(3,121)=-1.972, p=0.051 with and unstandardized beta of -7.503. However, this is on the border line of significance, meaning the results are almost significant. The moderator and independent variable are both still significant when adding the health consciousness variable. Impulsivity F(3,121)=2.032, p=0.044, and for the early versus late encountering of fruit and vegetables F(3,121)=2.604, p=0.010 (Appendix C, table 5).

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5. Discussion

In this study the main aim was to answer the research question:

This was done through an online experiment in which participants were asked to do their groceries for two days.

The findings from the online experiment confirmed the expectations that impulsive customers are more likely to buy more unhealthy food. Customers who were found to be impulsive purchased on average 7.6 calories more per product or 196.59 calories more in total for a shopping trip for two days. This means that an impulsive customer purchases almost 700 calories more per week than a less impulsive customer, this number increases the more

impulsive a customer is.

Although several theories discussed in the literature section would expect that the shopping trip in which customers were confronted with the fruit and vegetables early in the shopping trip would be more unhealthy than when they were confronted with the fruit and vegetables later, this was not the case in this online experiment. It was even the other way around, the customers who saw the healthy food early purchased less calories in total and per product than the customers who saw them later in their shopping trip. This is an interesting finding, since it supports the hypothesis in a way that the order in which customers see the product categories influences the healthiness of the shopping cart.

This contradicting finding speaks partly against the theory of licensing which states that after first being confronted with the healthy food, the healthy food choice will boost customers’ self-concepts, and reducing negative self-attributions associated with the purchase of the more unhealthy food (Khan and Dhar, 2006). What can explain why the licensing theory did not work for the online experiment conducted? Previous licensing studies were mostly about clothes, household products or money (donations), but not so much about food. However, these studies spoke about hedonic, luxury, indulgence or unhealthy and utilitarian, necessities, virtuous or healthy, which makes the assumption that the findings are

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they choose did not get rehearsals by seeing them in their shopping cart, because there was no shopping cart.

Evidence for why the findings are not as expected can be found in the article of Hui, Bradlow and Fader (2009), in their article they reason the theory of licensing the other way around, they state that when a consumer is first buying something from a vice category, this reduces their self-concept and increases the negative self-attribution, this increase is

associated with additional purchases from vice categories. So this means that the customers who are confronted with the fruit and vegetables late in their shopping trip are first confronted with the other product categories, of which some contain unhealthy food. Putting these

unhealthy food in their shopping cart reduces their self-concept and increases the negative self-attribution, this increase is associated with putting even more unhealthy food in their shopping cart. This can explain why the participants who were confronted with the fruit and vegetables late in their shopping trip purchased more calories than the people who were confronted with the healthy food early in their shopping trip.

There was no significant moderating effect of impulsivity on the effect of healthy food placement on the healthiness of the shopping cart. The model with the interaction showed no significant findings, however the model without the interaction showed significance for the effect of impulsivity on the healthiness of the shopping cart and also for the placement of fruit and vegetables on the healthiness of the shopping cart. So the early versus late confrontation with fruit and vegetables as well as the impulsivity of the customer have significant effects on the healthiness of the shopping cart, but only when these independent variables stand on itself, not when they are combined or they interact. This means there is no interaction between the early versus late confrontation with healthy food and the impulsivity of the customer,

meaning that an impulsive customer will not act more or less impulsive when the healthy food is early or late in their shopping trip.

5.1 Implications

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self-attribution, this way they are more likely to buy additional healthy products/healthier options. The current practice of most Dutch supermarkets, in which the fruit and vegetables are

encountered early in the shopping trip is good according to the findings of this paper. It unconsciously helps the customer to buy less calories then when the fruit and vegetables are encountered late in the shopping trip.

These implications may be even greater for the online supermarket, because marketers have greater control over the sequence of processes prior to the purchase decision. For

example, in an online supermarket environment marketers could make a pop-up window with additional purchases (“You might also like …”), these additional options should all be

healthy. By doing this the negative self-attribution of a customer buying an unhealthy option is reduced if they choose one of the healthier additional purchases. After putting the healthier product in their shopping cart they are more likely to continue their shopping trip choosing healthier options.

5.2 Limitations

As this research is one of the first to investigate the relation on the timing of

confrontation with healthy food on the healthiness of the shopping cart, some limitations have to be noted. Only 125 people participated in the study, which is not an extremely large

number, but there is no theoretical ground to expect that this study does not generalize to greater populations, only the gender of the participants consisted of more women than men, which is not the case in the real world. Also, the shopping trip did not include prices or other product information for the products, which is also likely to affect the products a customer might choose.

Furthermore, healthy and unhealthy is defined according to the number of calories a product contains per 100 gram and to the category it belongs to according to the

Voedingscentrum (healthy or unhealthy option). These two together make a relatively solid

understanding of what healthy and unhealthy food is. However, factor like fats and sugar are not directly taken into account in these measures.

5.3 Future research

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Another interesting question relates to the definition of healthy and unhealthy food. This research defines healthy and unhealthy food according to its calories and the category it belongs to, future research could look into other nutritious values like fat or sugar.

In this study the personality trait impulsivity is used as a moderator of the effect of healthy food placement on the healthiness of the shopping cart. This moderator lead to no significant results, future research could look into impulse buying in supermarket, but taking into account the shopping lists a lot of people make.

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6. Appendices

6.1 Appendix A – Product categories

Product categories and products with their calories per 100 gram and showed if healthy or unhealthy choice following the ‘Schijf van Vijf’ from the Voedingscentrum.

Fruit and vegetables

Bananas 89 healthy choice

Apples 52 healthy choice

Grapes 67 healthy choice

Oranges 51 healthy choice

Strawberries 33 healthy choice

Broccoli 34 healthy choice

Cauliflower 25 healthy choice

Green beans 31 healthy choice

Carrots 41 healthy choice

Brussel sprouts 43 healthy choice

Meat/vegetarian substitutes

Steak 271 healthy choice

Falafel 333

Hamburger 295

Minced meat 249

Vegetarian minced meat 246

Base of the meal

Rice 336

Spaghetti 158 unhealthy choice

Whole grain rigatoni 131 healthy choice

Wraps 320

Potatoes 86 healthy choice

Bread/crackers

White bread 247 unhealthy choice

Whole grain bread 247 healthy choice

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Biscuit 410

Whole grain crackers 380 healthy choice

Salty snacks

Chips 536 unhealthy choice

Mixed nuts 639 healthy choice

Cheese sticks 501 unhealthy choice

Drinks

Cola 41 unhealthy choice

Fruity drink 14

Sparkling water 0 healthy choice

Dairy

Milk 48 healthy choice

Yogurt 39 healthy choice

Cheese 403

Custard 91

Frozen products

Pizza 226 unhealthy choice

Ice cream 208 unhealthy choice

Snacks 244 unhealthy choice

Sweet snacks

Biscuits 502 unhealthy choice

Chocolate 535 unhealthy choice

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6.2 Appendix B - Online experiment

Online experiment with fruit and vegetables shown in the beginning of the shopping trip.

Q1 Introduction Welcome to this study and thank you for your willingness to participate. My name is Lieke Oost and I am a master student Marketing Management at the University of

Groningen. For my master thesis I am researching the food choices consumers make in a supermarket. This survey will take approximately 5 minutes of your time.

Please complete this study in a focused and serious fashion. Also, please answer honestly;I am interested in your opinion, there are no right or wrong answers.

This survey will work better on a computer or laptop than on a mobile device.

Every time you finish a question or have read the instructions, please click one the arrow in the bottom right corner.

Q2

Grocery shopping

In this part of the study, you will be asked to do your groceries for two days (breakfast, lunch,

dinner, snacks and drinks). For each category, you will be presented with different options and you

can choose more than one item per category. Please select the items you would normally purchase in this scenario (or closest to what you will normally purchase).

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After you finish grocery shopping, you will be asked some questions about the shopping trip and your personality.

Q7 Fruit and vegetables

▢

Bananas (1)

▢

Apples (2)

▢

Grapes (3)

▢

Oranges (4)

▢

Strawberries (5)

▢

Broccoli (6)

▢

Cauliflower (7)

▢

Green beans (8)

▢

Carrots (9)

▢

Brussel sprouts (10) Q9 Meat/vegetarian substitutes

▢

Steak (1)

▢

Falafel (2)

▢

Hamburger (3)

▢

Minced meat (4)

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Q10 Base of the meal

▢

Rice (1)

▢

Spaghetti (2)

▢

Whole grain rigatoni (3)

▢

Wraps (4)

▢

Potatoes (5) Q11 Bread/crackers

▢

White bread (1)

▢

Whole grain bread (2)

▢

Crackers (3)

▢

Beschuit (4)

▢

Whole grain crakcers (5) Q12 Salty snacks

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End of Block: Shopping trip beginning

Start of Block: Control question

Q30 Did you see the fruit and vegetables in the end or at the beginning of your shopping trip?

o

End (1)

o

Beginning (2)

End of Block: Control question

Q34

The following questions are about the shopping trip you just finished, how do you feel about the choices you made? Please indicate the extent to which you agree with each statement.

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Q15

The following questions are about your personality.Please indicate the extent to which you agree

with each statement.

Strongly disagree (1) Disagree (2) Somewhat disagree (3) Neither agree nor disagree (4) Somewhat agree (5) Agree (6) Strongly agree (7) I often buy things spontaneously. (1)

o

"Just do it" describes the way I buy things. (2)

o

I often buy things without thinking. (3)

o

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Q35 Please indicate the extent to which you agree with each statement. Strongly disagree (1) Disagree (2) Somewhat disagree (3) Neither agree nor disagree (4) Somewhat agree (5) Agree (6) Strongly agree (7) I reflect about my health a lot. (1)

o

I'm very self conscious about my health. (2)

o

I'm alert to changes in my health. (3)

o

I'm usually aware of my health. (4)

o

I take responsibilty

for the state of my health. (5)

o

I'm aware of the state of my health as I go trough the day. (6)

o

Q3 What is your gender?

o

Male (1)

o

Female (2) Q4 What is your age?

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Q5 Are you currently following a diet to lose weight?

o

Yes (1)

o

No (2)

Q31 To what extent do you feel hungry at the moment?

o

1. Not at all (1)

o

2. (2)

o

3. (3)

o

4. (4)

o

5. (5)

o

6. (6)

o

7. Extremely (7)

Q32 Do you have any dietary restrictions?

o

Yes, vegetarian (1)

o

Yes, vegan (2)

o

Yes, other (3) ________________________________________________

o

No (4)

Q16 Dear participant, This was the last question. In this study, you were asked to shop for grocery products. Afterwards, you were asked some questions about how impulsive you as a person are. The study researches how the impulsivity of a customer influences the healthiness of their shopping cart when fruit and vegetables are either placed in the beginning or at the end. I expect that the impulsivity of a customer influences the healthiness of the shopping cart in a positive way when fruit and

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6.3 Appendix C - SPSS output Table 1

T-test hypothesis 1, total number of calories

Grade Level n Mean SD t-cal Df P

Early 64 2909.52 917.699 -3.270 123 .001

Late 61 3536.33 1211.723

Table 2

T-test hypothesis 1, average number of calories per product

Grade Level n Mean SD t-cal Df P

Early 64 195.14 40.562

Late 61 214.01 38.817 -2.624 122.890 .010

Table 3

Regression testing hypothesis 2

Source B SE B β T P

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Table 4

Regression testing hypothesis 3

Model 1

Impulsivity 7.083 3.063 .200 2.312 .022

Early versus Late 17.873 7.083 .218 2.523 .013

Model 2

Impulsivity 9.302 4.538 .262 2.050 .043

Early versus late 32.384 22.983 .395 1.409 .161

Interaction early versus late and impulsivity

-4.091 6.163 -.200 -.664 .508

Table 5

Regression adding control variable to independent variables

Impulsivity 6.217 3.059 .175 2.032 .044

Health

consciousness

-7.503 3.804 -.170 -1.972 .051

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The influence of supermarkets layout on healthy eating