Complete aerial photographic coverage of an area by conventional photography with parallel flight lines and stereographic overlap between exposures in the line of flight.

(1) A sale between a willing buyer and a willing seller that are unrelated and are not acting under duress, abnormal pressure or undue influences. (2) A sale between two unrelated parties, both seeking to maximize their positions from the transaction.

An ordered arrangement of data, such as a listing of sales ratios, in order of magnitude.

The assembling of adjacent parcels of land into a single unit. Compare plottage.

The excess of the value of a large parcel of land formed from a number of smaller parcels over the sum of the values of the unassembled parcels.

(1) A value set on real estate and personal property by a government as a basis for levying taxes. (2) The monetary amount for a property as officially entered on the assessment roll for purposes of computing the tax levy. Assessed values differ from the assessor's estimate of actual (market) value for three major reasons: fractional assessment ratios, partial exemptions, and decisions by assessing officials to override market value The process of gathering and interpreting economic data to provide information that can be used by policymakers to formulate tax policy.

(1) In general, the official act of determining the amount of the tax base. (2) As applied to property taxes, the official act of discovering, listing, and appraising property, whether performed by an assessor, a board of review, or a court. (3) The value placed on property in the course of such act.

The total assessed value of all property within a designated area; the property tax base.

The status date for tax purposes. Appraised values reflect the status of the property and any partially completed construction as of this date.

The administrative area in which the officer or public body responsible for making the original assessment has jurisdiction. Note: The local assessment district is usually coterminous with a county, township, or city, but the state itself may be the assessment district for some types of property.

The degree to which assessments bear a consistent relationship to market value.

The common or overall ratio of assessed values to market values.

An appraisal bias such that high-value properties are appraised higher (or lower) than low-value properties in relation to market values. See price related differential.

(1) The fractional relationship an assessed value bears to the market value of the property in question. (2) By extension, the fractional relationship the total of the assessment roll bears to the total market value of all taxable property in a jurisdiction. See level of assessment and fractional assessments.

An investigation intended to determine the assessment ratio and assessment equity.

The transfer of any personal or real property or any rights in a property, by, for example, a deed, lease, or mortgage.

An automated valuation model ( style="color: black">AVM style="color: black">) is a mathematically based computer software program that produces an estimate of market value based on market analysis of location, market conditions, and real estate characteristics from information that was previously and separately collected. The distinguishing feature of an style="color: black"> AVM style="color: black"> is that it is a market appraisal produced through mathematical modeling. Credibility of an style="color: black">AVM style="color: black"> is dependent on the data used and the skills of the modeler producing the style="color: black">AVM style="color: black">.

The arithmetic mean of the absolute deviations of a set of numbers from a measure of central tendency, such as the median. Taking absolute values is generally understood without being stated. The average deviation of the numbers 4, 6, and 10 about their median (6) is (2 + 0 + 4) / 3 = 2. The average deviation is used in computing the coefficient of dispersion ( style="color: black">COD style="color: black">).