Problem definition

Currently, 120.000 people in Artsakh are under a blockade. The Lachin corridor, a road that runs through territory ruled by ethnic Armenians, is the only access point for people, food, and medical supplies. It is the sole connection between the Republic of Armenia and Artsakh. Azerbaijani protesters who have pitched tents outside of the town of Shusha have been blocking this road for more than a month (Nagorno-Karabakh: Empty shops and blockade pile pressure on Armenians, 2023). Delivering food and other essentials to these villages has become impossible. It is stated that the provocative actions of Azerbaijan may lead to a large-scale humanitarian disaster. The most important question for everyone was how many days can the products in the shop be enough for the population. Thus, the goal of the simulation is to examine in how many days all of the products will be finished for all 120.000 population.

Method

The simulation is made via NetLogo 6.3.0. NetLogo is a programmable modeling environment for simulating natural and social phenomena like the one described above (NetLogo, 2022). For instance, with NetLogo it is possible to simulate a fire emergency in a shopping center, the queues in a supermarket, the spreading of a virus, and more. This analysis is strongly based on the population activity and the number of available food supplies. Thus, I believe that NetLogo is very useful for this research.

Detailed description of the method

The method used simulates the flow of daily grocery shopping in Artsakh. Assuming that every day people go to the grocery shop to buy some food. First of all, let’s define the grocery store and create the shops. There are two types of shops in this analysis: supermarkets and convenience shops. According to the performed analysis, on average supermarkets prepare 10000 products daily, while the small-convenience stores have just 2000 products (Rooks, 2022). Meaning, that at the moment when the blockade started, the number of products in supermarkets stuck at 10000 in Artsakh and in convenience stores at 2000. Since that moment, each purchase contributed to the countback process. Taking into account the fact that the gap between these two numbers is huge, the simulation describes both types separately.

Supermarkets: As per the data based on my friends, family, and personal knowledge, there are no more than 50 supermarkets all over Artsakh. To be more realistic, there are approximately 30 supermarkets. Thus, the continuous variable named supermarket number is created as a range of numbers from 0 to 50.

Convenience stores: In Artsakh, The majority of daily purchases are conducted from the convenience stores nearby. In fact, there is a very big number of convenience stores in every neighborhood. Again based on my personal research, I've concluded that every province in Artsakh has approximately 80 convenience stores in total. There are 5 provinces in Artsakh, meaning that in total there are 400 convenience stores. The exogenous variable shop number defined the number of convenience stores. Secondly, besides the parameters discussed, the simulation has another six important parameters.

Population: This is an exogenous variable, however, according to real-life data, the population of Artsakh is 120000. Thus the research uses this number in the scope of its analysis.

People-shopping: This variable describes the number of people doing daily grocery shopping and is set based on several factors. First of all, children are not doing the grocery shopping and it’s needed to subtract their number from the total. According to the statistics, 26% of the whole population are children (Vision, 2022). Moreover, it is assumed that not everyone does the shopping, most probably just one family member. Thus, we withdraw the number of children from the total number and additionally divide the achieved number by two. As a result, in the real-life case, we get the number 44400. The variable is influenced by other model variables and therefore is endogenous.

```set people-shopping (population - (population * 26 / 100)) / 2
```

Number-of-products: The number of products is a global endogenous variable and is changed according to the shop data. As already discussed, the average number of convenience store products is 2000 and for supermarkets is 10000. Thus, in the simulation, the number of each type of shop is respectfully multiplied by the average number of products.

```set supermarket-products 10000;
set number-of-products ( shop-number * 2000 ) + ( supermarket-products * supermarket-number )
```

Food supply: The endogenous variable keeping track of the products left in percentages. In the beginning, this variable is set to be 100%. According to the number of products on the first day of the blockade, 100% is defined. Every time a person goes to the shop and buys some products, the food supply percentage decreases.

```set food-supply food-supply - minimal-percentage
```

Minimal-percentage: This endogenous variable is subtracted from the food supply variable every time a person does shopping. To calculate the percentage wasted on each shopping, the 100% is divided by the number of all products.

```set minimal-percentage 100 / number-of-products
```

Days: The last and most important endogenous variable answering the main question is the days. The initial value of days is set to zero. As soon as all shopping people reach the shops and do their shopping, the day is considered to be finished and a new day starts. The variable initialization is called on the moment each person does the groceries. In order to conduct the correct day calculation, this formula is being implemented.

```set days days + ( 1 / people-shopping )
```

Let's say the number of people shopping is 25. As soon as one of them arrives at the shop and does the shopping, they return “home” or to the initial starting position. At that moment, the day for them is finished. Logically, we would have to add 1 to the day count. However, if the number 1 was added on each successful shopping procedure, we would have the variable days set to 25 on the second day. Thus, on each successful shopping case, we divide 1 over the whole number of people shopping on that exact day (i.e. 25). Finally, we add it to the days variable. As a result, we get the number 1 at the end of each day.

Results

The result of the simulation completely answered the stated question of how many days the food will end in the real-life case. The final resulting number of days is 25. Therefore, with a population of 120000, no access to imports from the outer world, 44400 daily grocery shoppers, 400 convenience stores nearby, 30 supermarkets and a total of 1100000 products, the food would finish in the stores in just 25 days.

Conclusion

As a result of the simulation, it was found that in the stated conditions, the food would finish in 25 days. In fact, at the moment it is the 34th day of Artsakh blockade and as the simulation concluded, the food in the stores was finished exactly on the 25th day of the blockade (NEWS.am, 2023).

Citations

Nagorno-Karabakh: Empty shops and blockade pile pressure on Armenians. (2023). BBC News. [online] 6 Jan. Available at: https://www.bbc.com/news/world-europe-64174164.

NetLogo, N. (2022). NetLogo 5.1.0 User Manual. [online] ccl.northwestern.edu. Available at: http://ccl.northwestern.edu/netlogo/5.0/docs/whatis.html [Accessed 14 Jan. 2023].

Rooks, M. (2022). 30 000 Different Products And Counting: The Average Grocery Store. [online] icsid.org. Available at: https://www.icsid.org/uncategorized/how-many-products-are-in-a-typical-grocery-store/.

Vision, W. (2022). Children in Nagorno Karabakh are at risk. [online] www.wvi.org. Available at: https://www.wvi.org/newsroom/armenia/children-nagorno-karabakh-are-risk [Accessed 14 Jan. 2023].

NEWS.am (2023). Karabakh grocery stores are practically empty, number of closed stores in the capital Stepanakert increases. [online] news.am. Available at: https://news.am/eng/news/738341.html [Accessed 14 Jan. 2023].

Code

```breed [people person]
people-own [target]
breed [houses house]
globals [days food-supply number-of-products minimal-percentage supermarket-products]
to setup
clear-all
set-default-shape houses "house"
set days 0
set people-shopping (population - (population * 26 / 100)) / 2
set supermarket-products 10000;
set number-of-products ( shop-number * 2000 ) + ( supermarket-products * supermarket-number )
set food-supply 100
set minimal-percentage 100 / number-of-products
create-ordered-houses shop-number
[ fd max-pxcor ]
create-people people-shopping [
setxy 0 0
set size 1.2
set shape "person"
set target one-of houses
face target
]
reset-ticks
end
to go
if distance target = 0 and food-supply >= 0
[
setxy 0 0
set food-supply food-supply - minimal-percentage
set target one-of houses
face target
set days days + ( 1 / people-shopping )
]
ifelse distance target < 1
[ move-to target ]
[ fd 1 ]
]
tick
end
```