Consider the nature and demand of the factory! Demand and influence on geographical environment and surrounding facilities! List specific indicators! For example, the distance from raw materials affects the transportation cost, which can be counted as an indicator! The more indicators you can consider, the more detailed you will be! Then abstract the indicators and turn them into numbers. For example, the distance can be changed into kilometers, or the amount of materials that can be transported without the transportation cost of 100 people, and so on. Indicators can be abstracted as needed. The unit of each index is different, and the range of change is also different. Need to standardize the obtained data! Just bring the data after standard China into the algorithm! There are many related algorithms on the Internet. For example, calculating Nemerow index if you are the one and so on. You can go to Math China to see where the great god can give you more help!