toward profit but is provided as a "public good"and paid for out of taxes or voluntary contributions. Thus an evaluation of the desirability of alternative locations for a new police station or public health clinic would have to include a reckoning of costs; adequacy of service rendered to the community may be required. This is in fact an essential her case is nent rests or costs may monto a st changes of can also be canr esxe nnot be sure ss centers, zation de by t homogeneity e of costs and ions rather thar ole economic ard-nosed and wever, that rations are ch decision and with es called nonbusiness motivations 2.3 LOCA That is to say, th 2.3. 1 Loca One such element of relative advantage is the supply (availability, price, and quality) of ontransterables inputs. Local inputs are materials, supplies, or services that are present at a location and could not feasibly be brought in from elsewhere. The use of land is such an input, regardless of whether land is needed just as standing room or whether it also contains minerals or other constituents actually used in the process, as in "extractive" activities such as agriculture or mining5 toward profit but is provided as a "public good" and paid for out of taxes or voluntary contributions. Thus an evaluation of the desirability of alternative locations for a new police station or public health clinic would have to include a reckoning of costs; but on the returns side, difficult estimates of quality and adequacy of service rendered to the community may be required. Where public authorities make the decision, the most readily available measuring rod might well be political rather than economic: Which location will find favor with the largest number of voters at the next election? This is in fact an essential feature of a democratic society. Still more unlike the business firm example is that of the location of, say, a church or a nursing home. In neither case is success likely to be measured primarily in terms of numbers of people served or cost per person. Perhaps the judgment rests primarily on whether the facility is so located as to concentrate its beneficent effect on the particular neighborhood or group most needing or desiring it. Finally, suppose we are considering the residence location of a family. Here again, cost is an important element in the relative desirability of locations. This cost will include acquiring or renting the house and lot, plus maintenance and utilities expenses, plus taxes, plus costs of access to work, shopping, school, social, and other trip destinations of members of the family. The returns may be measured partly in money terms, if different sites imply different sets of job opportunities; but in any event there will be a large element of "amenity" reflecting the family's evaluation of houses, lots, and neighborhoods; and this factor will be difficult to measure in any way. There is a basic similarity in the location decision process of each of these cases: The definition of benefits or costs may differ in substance, but the goal of seeking to increase net benefit by a choice among alternative locations is common to all. Further, it is important to note that a family, a business establishment, or any other locational unit is likely to be ripe f or change in location only at certain junctures. There is ample and interesting evidence in Census reports that most changes of residence are associated with entry into the labor force, marriage, arrival of the first child, entry of the first child into school, last child leaving the household, widowhood, and retirement—though for specific families or individuals a move can also be triggered by a raise in salary, a new job opportunity, or an urban redevelopment project or other sudden change in the characteristics of a neighborhood. For all types of locational units, locational choices normally represent a substantial long-range commitment, since there are costs and inconveniences associated with any shift. This commitment has to be made in the face of uncertainty about the actual advantages involved in a location, and especially about possible future changes in relative advantage. Homebuyers cannot foresee with any certainty how the character of their chosen neighborhood (in terms of access, income level, ethnic mix, prestige, tax rates, or public services) will change—though they can be sure it will change. The business firm cannot be sure about how a location may be affected in the future by such things as shifting markets or sources of supply, transportation costs and services, congestion, changes in taxes and public services, or the location of competitors. Such uncertainties, along with the monetary and psychic costs of relocation, introduce a strong element of inertia. They also enhance the preferences for relatively "safe" locations such as "established" residential neighborhoods, business centers, or industrial areas. For business firms, the conservative tendency is reinforced by the fact that in a large corporate organization, decisions are made by managers whose earnings and promotion do not depend directly on the rate of profit made by the corporation so much as on maintenance of a satisfactory and stable earnings level and growth of output and sales. It is increasingly recognized that "profit maximization" may be an oversimplified conception of the motivating force behind business decisions, including those involving location.3 The effect of uncertainty from these various sources is to encourage spatial concentration of activities and homogeneity within areas. We should also expect a more sluggish response to change than would prevail in the absence of costs and uncertainties of locational choice. Further, if the firm is content with any of a number of "satisfactory" locations rather than insisting on finding the very best, there is substantial room for factors other than narrowly defined and measurable economic interests of the firm to enter the process of locational choice in an important way. It is for this reason that the personal preferences of individual decision-makers are present even in the hard-nosed and impersonal corporation. Statistical inquiries into the avowed reasons for business location consistently report, however, that "personal considerations" figure most conspicuously in small, new, and single-establishment firms. Such considerations are least often cited in explaining locations of branch plants by large concerns (this being of course the case in which decision makers themselves are least likely to have a substantial personal stake in the matter, since they themselves will probably not have to live at the chosen location). It would be wrong to label all personal elements of choice as irrational or as necessarily contributing to waste and inefficiency. The preference to locate one's job and one's home in a pleasant climate, a congenial community, and with convenient access to urban and cultural amenities may be hard to measure in dollars, but it is at least as real and sensible as one's preference for a higher money income. In the discussion of location factors that follows, the "inputs" and "outputs" should be understood to include even the less measurable and less tangible ones entailed in what are sometimes called nonbusiness motivations. 2.3 LOCATION FACTORS Despite the great variety of types of location units, all are sensitive in some degree to certain fundamental location factors. That is to say, the advantages of locations can be categorized (for any type of unit) into a standard set of a few elements. 2.3.1 Local Inputs and Outputs One such element of relative advantage is the supply (availability, price, and quality) of local or nontransferable4 inputs. Local inputs are materials, supplies, or services that are present at a location and could not feasibly be brought in from elsewhere. The use of land is such an input, regardless of whether land is needed just as standing room or whether it also contains minerals or other constituents actually used in the process, as in "extractive" activities such as agriculture or mining