Interpersonal Distance

Proxemic Theory’s interpersonal distance concept, ^{Reference Hall6} which is seen as an essential feature of bilateral relations between individuals ^{Reference Dickson and MacLachlan9} is considered an important form of nonverbal communication. ^{Reference Iachini, Coello and Frassinetti10} Behaviors related to interpersonal distance are often related to the protection of certain proximities that people perceive as private. ^{Reference Danesi11}

The basic dimensions of these invisible borders differ according to cultural, social, personality, and environmental variables, and these borders ensure that the appropriate distance is maintained between individuals. ^{Reference Riem, Kunst and Steenbakkers12,Reference Karakayali13} This physical distance is seen as a tendency to approach or avoid social stimuli ^{Reference Cohen and Shamay-Tsoory14} that often make people feel uncomfortable and threatened when that space is invaded. ^{Reference Kim, Kwak and Kim15} Interpersonal distance is sensitive not only to personal attitude toward another but also to gender, ^{Reference Uzzell and Horne16} age, ^{Reference Winogrond17} status and power, ^{Reference Peker, Booth and Eke18} and culture. ^{Reference Forston and Larson19}

The concept of “social distance” is based on Simmel’s ^{Reference Simmel20} theory of the stranger in the early 20th century. As a follower of Simmel, Bogardus ^{Reference Bogardus21} proposes that individuals focus on their feelings toward each other, and defined social distance as a function of the degree of mutual sympathetic understanding, and establishes a scale of “social distance” beginning with the level of “someone to marry” and ending with “someone to exile from the country.” Apart from this view, Hall’s ^{Reference Hall6} Proxemic Theory uses the term “interpersonal distance” and posits that it is a physical distance kept as personal breathing space, like an invisible bubble, that surrounds an individual representing an imaginary barrier to regulate intimacy with others by controlling the proximity of visual, tactile, auditory, and olfactory stimulation. This theory is based on the senses and mutual bodily stimulation effects between individuals, and focuses on the individual and his or her close approximations to others. The Proxemic Theory categorizes interpersonal distance in 4 intervals: (1) Intimate distance (0 in. - 18 in.); all senses are active and there is love, family, or close friend relationships in between. (2) Personal distance (1.5 ft - 4 ft); is the minimum comfortable distance between nontouching individuals, and this zone constitutes a small protective space. (3) Social distance (4 ft - 12 ft); is considered as the area where individuals do not care about each other and do not threaten each other. The distance of individuals at workplaces without disturbing each other can be given as an example. (4) Public distance (12 ft and beyond); is the distance at which one can take either evasive or defensive action if physically threatened. Formal situations such as conference and speech can be given as examples. To prevent possible confusion in terms, the term “social distance,” which is used by Bogardus, is also used by Hall to describe the third interval in his scale. It is believed that there is no intellectual influence between these 2 theoretical approaches, although they both explore almost the same aspect of social life. ^{Reference Rogers, Hart and Miike22}

In addition, Hall ^{Reference Hall6} categorizes cultures in 2 sets: contact and noncontact. Contact cultures are more inclined to touch each other, preferring shorted interpersonal distance while noncontact cultures show antipodal attitudes. He uses geographical division and suggests that contact culture dominates Southern European, Latin American, and Arabic and noncontact culture prevails in North American, Northern European, and Asian populations.

Little ^{Reference Little23} compares perception of personal space of Swedish, Scottish, and American people with that of Greek and Italian people and finds that perception of personal space of Greek and Italian people is narrower. Watson ^{Reference Watson24} in his research conducted on foreign students living in the United States, separates the students into 2 groups, similar to Hall, ^{Reference Hall6} according to countries with high contact culture (Arabs, Latin Americans, South East Europeans) and those with low contact culture (North Americans, North Europeans, Pakistanis, and Asians) and investigates their perception of personal space. He reveals that personal spaces of students from countries with contact culture are narrower than personal spaces of those from countries without contact culture.

Remland et al. ^{Reference Remland, Jones and Brinkman25} affirm that English, French, and Dutch people prefer greater personal space than Italian and Greek people. Beaulieu ^{Reference Beaulieu26} sorts different cultures in terms of largest personal space size preference order: Anglo-Saxons come first, Asians second, and Caucasians third, and Mediterranean people and Latinos prefer the shortest distance. Tiechuan ^{Reference Tiechuan27} claims that interpersonal distance preference for Spanish or Arabic people is much closer than for British people, and interpersonal distance for people in Western culture is greater than Eastern culture. Ke and Lian ^{Reference Ke and Lian28} report that interpersonal distance preferences differ between Chinese and American people. While Americans consider only spouses and children in their intimate space, Chinese people accept many more people in theirs. People waiting in crowded queues keep their personal spaces in American Society, whereas these spaces can be as close as physical contact in Chinese Society in similar circumstances. The impact of climate on interpersonal distance preferences is also examined. The individuals dwelling in hot climates are found to be friendlier and warmer than those living in cold climates (eg, Wei et al., Ven de Viliert, Ke and Lian, Sorokowska et al.). ^{Reference Sorokowska, Sorokowski and Hilpert7,Reference Ke and Lian28-Reference Van de Vliert30}

Interpersonal Distance and Contagion

From a medical perspective as a preventive measure, the interpersonal distance concept is frequently used as social distancing and being strongly advised to slow down the spread of contagion causing epidemics or pandemics (eg Ahmed et al., Fong et al., WHO, ECDC). ^{Reference Ahmed, Zviedrite and Uzicanin31-34} Studies focusing on the spread dynamic of other epidemics and pandemics in history also suggest the spread rate of contagious virus can be significantly restrained by practice and policies that emphasize social distancing (eg, Caley et al.). ^{Reference Caley, Philips and McCracken35}

During the COVID-19 pandemic, social distancing beyond the transmission range of virus is considered a key factor to stop virus spread from an infected individual to a healthy one and to flatten the curve of contagion spread to keep the total number of cases at any given time within the health systems’ means and capabilities. ^{Reference Kupferschmidt and Cohen36,37} The failure of society to practice social distance measures effectively often led to much more draconian and extremely costly governmental measures, such as quarantine, curfew, and lockdown to inhibit the speed of contagion spread. ^{Reference Woodward and Perper38,39} Some governments have delayed to take social distancing-related measures or gave inconsistent and confusing messages to people, making them perplexed, ^{Reference Horowitz, Bubola and Povoledo40} and some societies and groups simply resist the advised or instructed policies (eg, McMurtry and Zampano, Perrone). ^{Reference McMurtry and Zampano41,Reference Perrone42}

During our literature review, we find that there is one study exploring the association between interpersonal distance habits and the mortality caused by tuberculosis. This study used cross-country data and reported that greater national interpersonal distance preferences diminished the tuberculosis fatality rate. ^{Reference Gerace and Vorp43} However, we cannot locate any study examining the relation between national interpersonal distance preference and spread rate of an infection during a pandemic.

We believe that this relation is critical for understand the social aspects of COVID-19 spread dynamics and useful to develop tailored preventive and mitigation plans for different societies and also notable to fill the gap in the literature. Hence, we theorize a greater COVID-19 spread rate in countries where people prefer shorter interpersonal distances compared with countries where they prefer greater distances, and we developed the hypotheses below:

• H₁: Society’s preferred interpersonal distance (total) influences COVID-19 spread rate.

• H₂: Society’s preferred social distance influences COVID-19 spread rate.

• H₃: Society’s preferred personal distance influences COVID-19 spread rate.

• H₄: Society’s preferred intimate distance influences COVID-19 spread rate.

Methods and Data

For national interpersonal distances, we used national interpersonal distances preference as function of 3 variables, namely social distance (SD), personal distance (PD), and intimate distance (ID) of countries around world, which was measured by Sorokowska et al. ^{Reference Sorokowska, Sorokowski and Hilpert7} with a pioneering and comprehensive study, including 8943 participants from 42 different countries. For estimating interpersonal distance, participants were asked to fill a questionnaire including 3 graphical questions related to their preferred interpersonal distance. However, although the data set of national interpersonal distances data is not shown, we estimated sensitively using pixel/millimetric coordinate system approach (Jasc Paint Shop 8.0) based on the scaled graphic presented in the study. Although there are 4 intervals of interpersonal distance in Hall’s model, ^{Reference Hall6} we think the first 3 of them are the relevant approximations for viral transmission. Public distance, which is considered 12 ft and beyond is excluded from our research scope. This interval is not measured by Sorokowska et al. ^{Reference Sorokowska, Sorokowski and Hilpert7} as well.

To measure the increase in rate of spread of COVID-19, we used a simple exponential growth function (Equation 1), which is used for forecasting of the spread of an early phase of pandemic as stated by Anderson and May, ^{Reference Anderson and May44} Chowell et al., ^{Reference Chowell, Nishiura and Bettencourt45} Wallinga and Lipsitch, ^{Reference Wallinga and Lipsitch46} and Viboud et al. ^{Reference Viboud, Simonsen and Chowell47}

(1) $$T{C_{it}} = T{C_{i{t_0}}} \times {e^{{r_i}t}}$$

TC _it : Total COVID-19 cases of i^th country related to t^th day (April 7^th 2020),

TC _it0 : Total COVID-19 cases of i^th country related to the date of reaching the 100^th cumulative case,

r _i : The growth rate related to i^th country.

To compute the growth rate (r) for each country, data on COVID-19 total cases (covering the period between the date of reaching the 100th cumulative case and April 7, 2020) are collected from Our World in Data (OWD) formal website, ⁴⁸ which sorts out daily COVID-19 data from the WHO situation reports. Hong Kong and Uganda are excluded from analysis, due to lack of COVID-19 total cases data. The data set is presented in Appendix A.

Data Analysis

We examined the impacts of national interpersonal distances (social, personal, and intimate distance) on the growth rate of total cases of COVID-19 (GRTC) totally and separately. To see the total effect, the average interpersonal distance of each nation is computed by using the geometric mean formula. Additionally, because the dependent and independent variables in the models have different measurement units, a simple logarithmic regression model is proposed, as stated in Equation 2-5. Regression models are powerful tools to estimate and/or predict the dependent variable’s (population) mean by using 1 or more independent variables. ^{Reference Gujarati49}

(2) $$\ln GRT{C_i} = {\beta _0} + {\beta _1}\ln \,GMI{D_i} + {\varepsilon _i}$$

(3) $$\ln GRT{C_i} = {\beta _0} + {\beta _1}\ln \,S{D_i} + {\varepsilon _i}$$

(4) $$\ln GRT{C_i} = {\beta _0} + {\beta _1}\ln \,P{D_i} + {\varepsilon _i}$$

(5) $$\ln GRT{C_i} = {\beta _0} + {\beta _1}\ln \,I{D_i} + {\varepsilon _i}$$

GRTC _i : The natural logarithm of Growth Rate of Total Cases of COVID-19 of i ^th country;

GMID _i : The natural logarithm of geometric mean of interpersonal distance values of i ^th country;

SD _i : The natural logarithm of Social Distance value of i ^th country;

PD _i : The natural logarithm of Personal Distance value of i ^th country;

ID _i : The natural logarithm of Intimate Distance value of i ^th country;

ε _i : The error (residual) term in the regression model.