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Social Effects on Duration in Restaurants
Appetite, 1997, 29, 25–30
Social Effects on Duration in Restaurants
ROBERT SOMMER and JODIE STEELE University of California, Davis and State University of New York, Stony Brook, NY, U.S.A.
A nonreactive observational study in full-service restaurants showed group size to be positively correlated with length of stay. Among the serendipitous findings were the role of reading in lengthening duration and the paucity of lone diners in full-service restaurants. 1997 Academic Press Limited
I Naturalistic studies of intake have shown that groups remain longer and consume more food and beverages than do lone individuals (Sommer, 1965; Cutler & Storm, 1975; Plant, Kreitman, Miller & Duffy, 1977; Sommer & Sommer, 1989; Sykes, Rowley & Schaefer, 1990). Apart from a few studies taking place in student cafeteries and training facilities (Bell, Meiselman, Pierson & Reeve, 1994; Meiselman, Hedderly, Staddon & Pierson, 1994), most naturalistic observation studies have taken place in settings emphasizing beverage service. Very few systematic observational studies have been carried out in restaurants, perhaps the most common out-of-home consumption setting in the Western world. Krantz (1979) found that non-obese people purchased more in a cafeteria when they were accompanied than when they were alone. The reverse trend was found among obese individuals. (Neither group size nor duration were recorded in the study.) Observing people in fast-food and traditional restaurants, Klesges, Bartsch, Norwood, Kautzman & Haugrud, (1984) found that people ate more in groups than when alone. The present study explores group influence on duration within full-service restaurants. Because the method chosen was unobtrusive naturalistic observation, it was recognized from the outset that the study would not examine consumption per se but only length of time spent in the restaurant. Following the results of earlier observational studies in locations emphasizing beverage service and the diary studies of de Castro and de Castro (1989) it was predicted that group size would influence length of stay in full-service restaurants. The present research turned out to have serendipitous aspects that will be described in the results. We would like to express our appreciation to Barbara Sommer and Ira Sy for their assistance. Correspondence to: Robert Sommer, Psychology Department, University of California, Davis, CA 95616-8686, U.S.A. 0195–6663/97/040025+06 $25.00/0/ap960062
1997 Academic Press Limited
26
R. SOMMER AND J. STEELE
M The procedures were similar to those used by Sommer (1965) in pubs and Sommer and Sommer (1989) in coffee houses. A researcher enters the setting as a customer, sits at a table, orders, and consumes the items in a leisurely fashion, in order to lengthen the observational session. While seated, the observer unobtrusively records information on the next three lone individuals and next three group members (one member in each group is chosen arbitrarily) who enter the restaurant after the researcher has been seated. By selecting a similar number of lone and group customers in each setting, setting effects on duration should be equalized for lone and group customers. All patrons are observed from the moment they enter the restaurant. This requirement was instituted to avoid bias in choosing observational subjects and to omit people already seated, whose entry time into the restaurant is unknown. Information was restricted to those items that could be observed reliably and unobtrusively, including entrance and departure time, gender, age in deciles, group size, and whether or not the individual was reading. All restaurants were located in Northern and Central California. There were 27 visits to five coffee shops, and 30 visits to 20 traditional restaurants.
Taxonomy of Restaurants The research team initially employed a single conception of restaurants following the dictionary definition as “a place where meals could be bought and eaten; an eating house”. This excluded fast-food restaurants emphasizing take-out service since we were interested in meal duration. Also excluded were pizza parlors and similar restaurants where ordering is done at a counter and individuals seat and serve themselves, which appeared to call for a separate investigation. The need for a further distinction between coffee shops and traditional restaurants became apparent midway through the research. The term coffee shop describes low cost, high volume restaurants featuring snack foods and beverage service as well as meals, with a premium on quick service, and typically with a number of counter seats. Often a coffee shop is open 24 hours a day and affiliated with a chain, although neither of the latter conditions was necessary for inclusion in the study. In contrast, the traditional restaurant offers primarily or exclusively table service involving full meals, the food is moderate to high priced, and service is available only at designated meal hours. From a behavioral standpoint, service in a traditional restaurant is more leisurely than in a coffee shop. Reading, playing games, and table-hopping are more common in coffee shops where group size tends to be fluid, relative to traditional restaurants where party size tends to be fixed for the duration of a meal. Levels of illumination tend to be higher in coffee shops than in traditional restaurants, which provide more environmental support for reading in the coffee shop. Because of these differences, the results will be presented separately for coffee shops and for traditional restaurants.
Incomplete Sessions There were nine sessions in which the observer departed before a customer being observed. Three of the incomplete sessions involved lone customers and six involved
27
SOCIAL EFFECTS
T 1 Duration as a function of reading and group membership in coffee shops Mean duration in minutes Alone Not reading (N) Reading (N)
30·2 (9) 38·9 (34) Fgroup 9·98, p<0·01 Fread 4.71, p<0·05
Groups 42·8 (74) 51·2 (13)
group members, which was similar to the overall ratio of lone and group customers in the study. For the incomplete sessions, time was measured up to the observer’s departure. R Coffee Shops A total of 130 customers were observed in coffee shops. Although the research design had called for equal numbers (up to three) lone individuals and group members for each observational session, the final sample contained 43 lone individuals and 87 group members. There were several reasons for the larger number of group members in the sample. Eleven loners were joined by others during a session, converting them into group members. Second, and more significant, there were fewer lone individuals than groups in the coffee shops. The activities engaged in by the loners and groups were very different in the setting. Of the lone individuals observed, 79% were reading newspapers, books, or other materials at some point during the meal compared to 15% of people in groups. Of the 13 instances where people in groups were reading, 12 occurred in groups of two, and only one person in a group of three or larger was observed reading. Because of the large number of coffee house patrons who were reading, and the likelihood that this would influence duration as had occurred in a previous study in coffee houses which did not serve meals (Sommer & Sommer, 1989), a two-way ANOVA was conducted using group status (lone vs. group customers) and reading as independent variables, with meal duration as the dependent variable. Table 1 shows both main effects to be significant while the interaction was not. Groups remained longer in the coffee shops than did lone individuals, and those reading stayed longer than those not reading. The differences were significant both when lone individuals who were joined by others were classified as group members and when they were excluded from the analysis. Traditional Restaurants It proved even more difficult in traditional restaurants than in coffee shops to locate lone customers. Although the research design had called for equal numbers
28
R. SOMMER AND J. STEELE
T 2 Duration for lone diners and groups in traditional restaurants Mean duration in minutes
All diners (N) Matched pairs (N)
Alone
Groups
t
p
36·5 (21) 35·2 (17)
50·3 (73) 46·8 (17)
4·12
0·01
2·56
0·05
of lone customers and group members during each observation session (up to three in each restaurant), the 94 customers consisted of 21 lone individuals and 73 group members. The difference was due to the paucity of lone customers in traditional restaurants. The implications of the lack of lone customers will be considered in the discussion. Reading was less frequent in traditional restaurants than in coffee shops and when it occurred was done exclusively by customers sitting alone. Of those sitting alone, 57% were observed reading while none of the group members were reading. The absence of reading among group members precluded the two-way ANOVA used in the coffee shops. Instead, correlations and t-tests were conducted within samples to test main effects. The first analysis involved the total sample of 94 customers observed in traditional restaurants. The second test, considered more precise since it controls for setting variables, compares matched samples of lone customers and group members within each restaurant. The gain in precision by using matched pairs is offset by the loss in sample size, since only 17 matched pairs of loners and group members within the same settings were observed. The two analyses complement each other and will be presented in order. Correlations were used with the entire sample, which included all variations in group size. A separate analysis was subsequently undertaken comparing lone diners with groups of all sizes combined. The two analyses yielded similar results. Consistent with the findings of de Castro and Brewer (1992), group size was positively associated with meal duration (r=0·42, p<0·001). When lone individuals are excluded, the correlation between group size and duration was 0·46 (p<0·01). Table 2 shows that lone customers remained an average of 36·5 min compared to an average of 50·3 min for group members. There were no significant interactions between group size and age or gender, or between age or gender and duration.
Matched Pairs The original research design had called for equal numbers (up to three) of lone customers and group members within each setting in order to control for background variables. However, the paucity of lone customers made it difficult to find matched pairs. For 17 of the 30 observation sessions (57%) in traditional restaurants, no lone customers were observed. In order to conduct the matched-pair analysis, the study was extended several months. Even with the extension, only 17 matched pairs (lone
SOCIAL EFFECTS
29
individuals and group members who arrived at the restaurant after the observer had been seated) were located. For the 17 matched pairs, lone customers remained an average of 35·2 minutes compared to 46·8 min for group members. Reading Of the 21 lone customers observed in the traditional restaurants, 12 (57%) were seen reading at some point during the meal. Those reading had an average duration of 39·0 minutes compared to 33·2 minutes for those not reading. While the difference was in the predicted direction, it was not statistically significant, t (19)=1·06, p= 0·30.
D The present research was made difficult by the scarcity of lone diners in restaurants. In the conceptualization of the study, eating alone was part of the independent variable. Yet at another level, the paucity of lone diners is perhaps the strongest evidence in the present study for the importance of social factors in restaurant dining. The ratio of lone to group diners in the sample represents a serious overestimation of the actual ratio of lone to group diners in the restaurants. In 8% of the visits to the coffee shops and 57% of the visits to traditional restaurants, not a single lone diner was observed who met the conditions of the study in terms of arriving after the observer had been seated. People choose to eat in restaurants in groups. This may reflect a self-consciousness about eating alone when others are in group (the fear of being perceived as unable to find a partner or friend) or the possibility of diminished enjoyment dining alone. There has been little or no discussion in the literature of the paucity of lone dining in restaurants. It would not be a factor in experimental studies where the investigator establishes group size and has not been mentioned in any of the published studies using diary methods. We have no doubt that traditional restaurants exist where there are more lone customers than were found in the present study. Such restaurants would probably be found in neighbourhoods with a high percentage of people living alone or that cater to business customers on sales trips. Group effects on duration were found in both the coffee shops and traditional restaurants. These results support the time extension model proposed by the de Castros and their associates in that meal duration was positively associated with group size. Reading was a serendipitous variable in the present study. Reading had not been mentioned in any of the experimental or diary studies of food intake we have seen. In the present research, the significant role of reading in food service settings could not be ignored. Reading is a common activity in coffee shops, more common among lone than group customers, very uncommon among group customers in traditional restaurants, and serves to lengthen duration in both settings. There is no interaction between group status and reading, but each operates independently to increase duration. This raises some interesting theoretical and practical questions. Facilitation theory looks at the effects of social stimuli on activity. However, reading in public locations is primarily an asocial activity, the province of people who are alone, and its role may be to supplant or substitute for other types of activities. This would place it in the category of a social inhibitor.
30
R. SOMMER AND J. STEELE
Limitations Because this was planned as a naturalistic nonreactive study that would sample different coffee houses and restaurants, we were limited in the type of information that could be obtained. We did not study intake but only duration in a setting where food and beverages are consumed. There is however research indicating that duration in such settings is positively associated with intake (e.g. Sommer, 1965; Plant, Kreitman, Miller & Duffy, 1977; Clendenen, Herman & Polivy, 1994). The variables measured in the present study are imprecise, reflective of the limitations in the method used. Reading was a dichotomous variable (present/absent) rather than being measured by amount or type of material read. Nor was an attempt made to measure intake directly. These are significant limitations. On the positive side, the study breaks new ground in applying systematic naturalistic observation to important intake settings. The study calls attention to the paucity of lone diners in such settings and the role of reading as a social inhibitor. Our hope is that others will extend and focus these findings using more precise measures.
R Sommer, R. (1965). The isolated drinker in the Edmonton beverage room. Quarterly Journal of Studies on Alcohol, 26, 95–110. Cutler, R. E. & Storm, T. (1975). Observational study of alcohol consumption in natural settings: The Vancouver Beer Parlor. Journal of Studies on Alcohol, 36, 1173–1183. de Castro, J. M. & Brewer, E. M. (1992). The amount eaten in meals by humans is a power function of the number of people present. Physiology and Behavior, 51, 121–125. Clerdenen, V. I., Herman, C. P. & Polivy, J. (1994). Social facilition of eating among friends and strangers. Appetite, 22, 11–24. Plant, M. A., Kreitman, N. & Miller, T. (1977). Observing public drinking. Journal of Studies on Alcohol, 38, 867–880. Sommer, R. & Sommer, B. A. (1989). Social facilitation in coffeehouses. Environment and Behavior, 21, 651–666. Sykes, R. E., Rowley, R. D. & Schaefer, J. M. (1990). Effects of group participation on drinking behaviors in public bars. In J. W. Neuliep (Ed.). Replication research in the social sciences. Pp. 373–390. Newbury Park, California: Sage. Bell, R., Meiselman, H. L., Pierson, B. J. & Reeve, W. G. (1994). Effects of adding an Italian theme to a restaurant on perceived ethnicity, acceptability, and selection of foods. Appetite, 22, 11–24. Meiselman, H. L., Hedderly, D., Staddon, S. L. & Pierson, B. (1994). Effect of effort on meal selection and acceptability in a student cafeteria. Appetite, 23, 43–55. Krantz, D. S. (1979). A naturalistic study of social influences on meal size among moderately obese and non-obese subjects. Psychosomatic Medicine, 41, 19–26. Klesges, R. C., Bartsch, D., Norwood, J. D., Kautzman, D. & Haugrud, S. (1984). The effects of selected social and environmental variables on the eating behavior of adults in the natural environment. International Journal of Eating Disorders, 3, 35–41. Received 23 January 1996, revision 7 August 1996
Social Effects on Duration in Restaurants
ROBERT SOMMER and JODIE STEELE University of California, Davis and State University of New York, Stony Brook, NY, U.S.A.
A nonreactive observational study in full-service restaurants showed group size to be positively correlated with length of stay. Among the serendipitous findings were the role of reading in lengthening duration and the paucity of lone diners in full-service restaurants. 1997 Academic Press Limited
I Naturalistic studies of intake have shown that groups remain longer and consume more food and beverages than do lone individuals (Sommer, 1965; Cutler & Storm, 1975; Plant, Kreitman, Miller & Duffy, 1977; Sommer & Sommer, 1989; Sykes, Rowley & Schaefer, 1990). Apart from a few studies taking place in student cafeteries and training facilities (Bell, Meiselman, Pierson & Reeve, 1994; Meiselman, Hedderly, Staddon & Pierson, 1994), most naturalistic observation studies have taken place in settings emphasizing beverage service. Very few systematic observational studies have been carried out in restaurants, perhaps the most common out-of-home consumption setting in the Western world. Krantz (1979) found that non-obese people purchased more in a cafeteria when they were accompanied than when they were alone. The reverse trend was found among obese individuals. (Neither group size nor duration were recorded in the study.) Observing people in fast-food and traditional restaurants, Klesges, Bartsch, Norwood, Kautzman & Haugrud, (1984) found that people ate more in groups than when alone. The present study explores group influence on duration within full-service restaurants. Because the method chosen was unobtrusive naturalistic observation, it was recognized from the outset that the study would not examine consumption per se but only length of time spent in the restaurant. Following the results of earlier observational studies in locations emphasizing beverage service and the diary studies of de Castro and de Castro (1989) it was predicted that group size would influence length of stay in full-service restaurants. The present research turned out to have serendipitous aspects that will be described in the results. We would like to express our appreciation to Barbara Sommer and Ira Sy for their assistance. Correspondence to: Robert Sommer, Psychology Department, University of California, Davis, CA 95616-8686, U.S.A. 0195–6663/97/040025+06 $25.00/0/ap960062
1997 Academic Press Limited
26
R. SOMMER AND J. STEELE
M The procedures were similar to those used by Sommer (1965) in pubs and Sommer and Sommer (1989) in coffee houses. A researcher enters the setting as a customer, sits at a table, orders, and consumes the items in a leisurely fashion, in order to lengthen the observational session. While seated, the observer unobtrusively records information on the next three lone individuals and next three group members (one member in each group is chosen arbitrarily) who enter the restaurant after the researcher has been seated. By selecting a similar number of lone and group customers in each setting, setting effects on duration should be equalized for lone and group customers. All patrons are observed from the moment they enter the restaurant. This requirement was instituted to avoid bias in choosing observational subjects and to omit people already seated, whose entry time into the restaurant is unknown. Information was restricted to those items that could be observed reliably and unobtrusively, including entrance and departure time, gender, age in deciles, group size, and whether or not the individual was reading. All restaurants were located in Northern and Central California. There were 27 visits to five coffee shops, and 30 visits to 20 traditional restaurants.
Taxonomy of Restaurants The research team initially employed a single conception of restaurants following the dictionary definition as “a place where meals could be bought and eaten; an eating house”. This excluded fast-food restaurants emphasizing take-out service since we were interested in meal duration. Also excluded were pizza parlors and similar restaurants where ordering is done at a counter and individuals seat and serve themselves, which appeared to call for a separate investigation. The need for a further distinction between coffee shops and traditional restaurants became apparent midway through the research. The term coffee shop describes low cost, high volume restaurants featuring snack foods and beverage service as well as meals, with a premium on quick service, and typically with a number of counter seats. Often a coffee shop is open 24 hours a day and affiliated with a chain, although neither of the latter conditions was necessary for inclusion in the study. In contrast, the traditional restaurant offers primarily or exclusively table service involving full meals, the food is moderate to high priced, and service is available only at designated meal hours. From a behavioral standpoint, service in a traditional restaurant is more leisurely than in a coffee shop. Reading, playing games, and table-hopping are more common in coffee shops where group size tends to be fluid, relative to traditional restaurants where party size tends to be fixed for the duration of a meal. Levels of illumination tend to be higher in coffee shops than in traditional restaurants, which provide more environmental support for reading in the coffee shop. Because of these differences, the results will be presented separately for coffee shops and for traditional restaurants.
Incomplete Sessions There were nine sessions in which the observer departed before a customer being observed. Three of the incomplete sessions involved lone customers and six involved
27
SOCIAL EFFECTS
T 1 Duration as a function of reading and group membership in coffee shops Mean duration in minutes Alone Not reading (N) Reading (N)
30·2 (9) 38·9 (34) Fgroup 9·98, p<0·01 Fread 4.71, p<0·05
Groups 42·8 (74) 51·2 (13)
group members, which was similar to the overall ratio of lone and group customers in the study. For the incomplete sessions, time was measured up to the observer’s departure. R Coffee Shops A total of 130 customers were observed in coffee shops. Although the research design had called for equal numbers (up to three) lone individuals and group members for each observational session, the final sample contained 43 lone individuals and 87 group members. There were several reasons for the larger number of group members in the sample. Eleven loners were joined by others during a session, converting them into group members. Second, and more significant, there were fewer lone individuals than groups in the coffee shops. The activities engaged in by the loners and groups were very different in the setting. Of the lone individuals observed, 79% were reading newspapers, books, or other materials at some point during the meal compared to 15% of people in groups. Of the 13 instances where people in groups were reading, 12 occurred in groups of two, and only one person in a group of three or larger was observed reading. Because of the large number of coffee house patrons who were reading, and the likelihood that this would influence duration as had occurred in a previous study in coffee houses which did not serve meals (Sommer & Sommer, 1989), a two-way ANOVA was conducted using group status (lone vs. group customers) and reading as independent variables, with meal duration as the dependent variable. Table 1 shows both main effects to be significant while the interaction was not. Groups remained longer in the coffee shops than did lone individuals, and those reading stayed longer than those not reading. The differences were significant both when lone individuals who were joined by others were classified as group members and when they were excluded from the analysis. Traditional Restaurants It proved even more difficult in traditional restaurants than in coffee shops to locate lone customers. Although the research design had called for equal numbers
28
R. SOMMER AND J. STEELE
T 2 Duration for lone diners and groups in traditional restaurants Mean duration in minutes
All diners (N) Matched pairs (N)
Alone
Groups
t
p
36·5 (21) 35·2 (17)
50·3 (73) 46·8 (17)
4·12
0·01
2·56
0·05
of lone customers and group members during each observation session (up to three in each restaurant), the 94 customers consisted of 21 lone individuals and 73 group members. The difference was due to the paucity of lone customers in traditional restaurants. The implications of the lack of lone customers will be considered in the discussion. Reading was less frequent in traditional restaurants than in coffee shops and when it occurred was done exclusively by customers sitting alone. Of those sitting alone, 57% were observed reading while none of the group members were reading. The absence of reading among group members precluded the two-way ANOVA used in the coffee shops. Instead, correlations and t-tests were conducted within samples to test main effects. The first analysis involved the total sample of 94 customers observed in traditional restaurants. The second test, considered more precise since it controls for setting variables, compares matched samples of lone customers and group members within each restaurant. The gain in precision by using matched pairs is offset by the loss in sample size, since only 17 matched pairs of loners and group members within the same settings were observed. The two analyses complement each other and will be presented in order. Correlations were used with the entire sample, which included all variations in group size. A separate analysis was subsequently undertaken comparing lone diners with groups of all sizes combined. The two analyses yielded similar results. Consistent with the findings of de Castro and Brewer (1992), group size was positively associated with meal duration (r=0·42, p<0·001). When lone individuals are excluded, the correlation between group size and duration was 0·46 (p<0·01). Table 2 shows that lone customers remained an average of 36·5 min compared to an average of 50·3 min for group members. There were no significant interactions between group size and age or gender, or between age or gender and duration.
Matched Pairs The original research design had called for equal numbers (up to three) of lone customers and group members within each setting in order to control for background variables. However, the paucity of lone customers made it difficult to find matched pairs. For 17 of the 30 observation sessions (57%) in traditional restaurants, no lone customers were observed. In order to conduct the matched-pair analysis, the study was extended several months. Even with the extension, only 17 matched pairs (lone
SOCIAL EFFECTS
29
individuals and group members who arrived at the restaurant after the observer had been seated) were located. For the 17 matched pairs, lone customers remained an average of 35·2 minutes compared to 46·8 min for group members. Reading Of the 21 lone customers observed in the traditional restaurants, 12 (57%) were seen reading at some point during the meal. Those reading had an average duration of 39·0 minutes compared to 33·2 minutes for those not reading. While the difference was in the predicted direction, it was not statistically significant, t (19)=1·06, p= 0·30.
D The present research was made difficult by the scarcity of lone diners in restaurants. In the conceptualization of the study, eating alone was part of the independent variable. Yet at another level, the paucity of lone diners is perhaps the strongest evidence in the present study for the importance of social factors in restaurant dining. The ratio of lone to group diners in the sample represents a serious overestimation of the actual ratio of lone to group diners in the restaurants. In 8% of the visits to the coffee shops and 57% of the visits to traditional restaurants, not a single lone diner was observed who met the conditions of the study in terms of arriving after the observer had been seated. People choose to eat in restaurants in groups. This may reflect a self-consciousness about eating alone when others are in group (the fear of being perceived as unable to find a partner or friend) or the possibility of diminished enjoyment dining alone. There has been little or no discussion in the literature of the paucity of lone dining in restaurants. It would not be a factor in experimental studies where the investigator establishes group size and has not been mentioned in any of the published studies using diary methods. We have no doubt that traditional restaurants exist where there are more lone customers than were found in the present study. Such restaurants would probably be found in neighbourhoods with a high percentage of people living alone or that cater to business customers on sales trips. Group effects on duration were found in both the coffee shops and traditional restaurants. These results support the time extension model proposed by the de Castros and their associates in that meal duration was positively associated with group size. Reading was a serendipitous variable in the present study. Reading had not been mentioned in any of the experimental or diary studies of food intake we have seen. In the present research, the significant role of reading in food service settings could not be ignored. Reading is a common activity in coffee shops, more common among lone than group customers, very uncommon among group customers in traditional restaurants, and serves to lengthen duration in both settings. There is no interaction between group status and reading, but each operates independently to increase duration. This raises some interesting theoretical and practical questions. Facilitation theory looks at the effects of social stimuli on activity. However, reading in public locations is primarily an asocial activity, the province of people who are alone, and its role may be to supplant or substitute for other types of activities. This would place it in the category of a social inhibitor.
30
R. SOMMER AND J. STEELE
Limitations Because this was planned as a naturalistic nonreactive study that would sample different coffee houses and restaurants, we were limited in the type of information that could be obtained. We did not study intake but only duration in a setting where food and beverages are consumed. There is however research indicating that duration in such settings is positively associated with intake (e.g. Sommer, 1965; Plant, Kreitman, Miller & Duffy, 1977; Clendenen, Herman & Polivy, 1994). The variables measured in the present study are imprecise, reflective of the limitations in the method used. Reading was a dichotomous variable (present/absent) rather than being measured by amount or type of material read. Nor was an attempt made to measure intake directly. These are significant limitations. On the positive side, the study breaks new ground in applying systematic naturalistic observation to important intake settings. The study calls attention to the paucity of lone diners in such settings and the role of reading as a social inhibitor. Our hope is that others will extend and focus these findings using more precise measures.
R Sommer, R. (1965). The isolated drinker in the Edmonton beverage room. Quarterly Journal of Studies on Alcohol, 26, 95–110. Cutler, R. E. & Storm, T. (1975). Observational study of alcohol consumption in natural settings: The Vancouver Beer Parlor. Journal of Studies on Alcohol, 36, 1173–1183. de Castro, J. M. & Brewer, E. M. (1992). The amount eaten in meals by humans is a power function of the number of people present. Physiology and Behavior, 51, 121–125. Clerdenen, V. I., Herman, C. P. & Polivy, J. (1994). Social facilition of eating among friends and strangers. Appetite, 22, 11–24. Plant, M. A., Kreitman, N. & Miller, T. (1977). Observing public drinking. Journal of Studies on Alcohol, 38, 867–880. Sommer, R. & Sommer, B. A. (1989). Social facilitation in coffeehouses. Environment and Behavior, 21, 651–666. Sykes, R. E., Rowley, R. D. & Schaefer, J. M. (1990). Effects of group participation on drinking behaviors in public bars. In J. W. Neuliep (Ed.). Replication research in the social sciences. Pp. 373–390. Newbury Park, California: Sage. Bell, R., Meiselman, H. L., Pierson, B. J. & Reeve, W. G. (1994). Effects of adding an Italian theme to a restaurant on perceived ethnicity, acceptability, and selection of foods. Appetite, 22, 11–24. Meiselman, H. L., Hedderly, D., Staddon, S. L. & Pierson, B. (1994). Effect of effort on meal selection and acceptability in a student cafeteria. Appetite, 23, 43–55. Krantz, D. S. (1979). A naturalistic study of social influences on meal size among moderately obese and non-obese subjects. Psychosomatic Medicine, 41, 19–26. Klesges, R. C., Bartsch, D., Norwood, J. D., Kautzman, D. & Haugrud, S. (1984). The effects of selected social and environmental variables on the eating behavior of adults in the natural environment. International Journal of Eating Disorders, 3, 35–41. Received 23 January 1996, revision 7 August 1996