Limitations and Assumptions

The findings presented in the potential impacts section are based on a model that is created to better understand openspace scoring systems, and to compare scoring systems. The following section discusses the limitations of the model presented in this analysis, and the assumptions that had to be made to make it work.

Parcels Will Not Be Bought In The Order They Are Ranked

When a parcel is purchased as openspace, the owner of the parcel has to agree to sell their land. Also, the organization protecting the openspace has to have money available to purchase the land. These events must coincide to allow the transaction to take place. Follow this link for more information about how land trusts purchase openspace. There is no way of knowing at a large scale, which land owners will want to sell their property to the town, so there is no way of assessing if the parcels that are ranked high will actually be able to be protected. This means that they probably will not be bought in the order that they are ranked.

Despite this reality, this assumption still creates a useful way of analyzing openspace scoring systems. Purchasing the parcels in the order they are ranked is what the openspace policy intends to accomplish.

The purpose of openspace scoring systems is to evaluate potential purchases in a systematic way. This system helps the town choose between parcels when more then one parcel becomes available for purchase at any given time. The scoring system influences the type of land that is protected through the aggregate of these decisions. If the policy calls for purchasing parcels with a large amount of co-occurring resources, these parcels will tend to be purchased more often then those without large amounts of co-occurring resources.

The model in this analysis, assumes the most drastic case of policy implementation. It assumes that every property can be purchased at any given time, and that the choices that are made between the parcels are all that matters. The model is likely to amplify the influence the policy has over the process of purchasing openspace.

Tax Assessors Database

It is inaccurate to equate the assessed value of a parcel to the market value of that parcel. The assessment used in this analysis was conducted in 1995, and the real estate market in Charlestown has changed substantially since then. The assessed value for any given property is most likely significantly less then the cost of purchasing that property. There is no acceptable way of relating assessed value to market value in Charlestown, so all of the analysis in this study are conducted with assessed value.

Market value of properties was estimated in some instances by comparing assessed value of properties that were recently sold with their assessed value.

Despite the limitations of using the assessed value of land, the relative assessed value is still very useful. When comparing the cost of parcels, assessed value is a useful tool to use. It allows the overall difference in price per area, which is crucial to the scoring system analysis, to be estimated.