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Residential Glossary of Terms

     The living area in a house not including the basement.
     Improvements other than the principal buildings.
     According to value.
     A tax levied in proportion to the value of the thing(s) being taxed. Exclusive of exemptions, use-value assessment provisions, and the like, the property tax is an ad valorem tax.
     Modifications in the reported value of a variable, such as sale price. For example, adjustments can be used to estimate market value in the sales comparison approach by modifications for differences between comparable and subject properties.
     (1) The act of estimating the money value of property.

(2) The money value of property as estimated by an appraiser.

(3) Of or pertaining to appraising and related functions, for example, appraisal practice, appraisal services. Compare assessment.
     The date as of which a property's value is estimated.
     (1) The ratio of the appraised value to an indicator of market value.

(2) By extension, an estimated fractional relationship between the appraisals and market values of a group of properties.
     A ratio study using independent appraisals as indicators of market value.
     The oral or written communication of a completed appraisal.
     The division of the APPRAISAL FOUNDATION that develops, publishes, interprets, and amends the Uniform Standards of Professional Appraisal Practice on behalf of appraisers and users of appraisal services.
     The ratio of the appraised value to the sale price (or adjusted sale price) of a property; a simple indication of appraisal accuracy.
     One who estimates the value of property; more commonly, one of a group of professionally skilled persons holding themselves out as experts in valuation.
     A geographic area defined and named by the Department of Assessments. These areas typically encompass properties within a group of neighborhoods that are more or less equally subject to economic forces that largely determine the value of the properties in question.
     A value set on real estate and personal property by a government as a basis for levying taxes.
     (verb) The official act of discovering, listing, and appraising property. (noun) The value placed on property in the course of such act.
     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 than low-value properties in relation to market values.
     (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.
     An appraisal bias such that high-value properties are appraised lower than low-value properties in relation to market values.
     The ratio of the assessed value to the sale price (or adjusted sale price) of a property.
     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 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.
     A statistic is said to be biased if the expected value of that statistic is not equal to the population parameter being estimated. A process is said to be biased if it produces results that vary systematically with some factor that should be irrelevant. In assessment administration, assessment progressivity (regressivity) is one kind of possible bias.
     Relative to age and grade. Coded 1-5.

1 = Poor- Worn out. Repair and overhaul needed on painted surfaces, roofing, plumbing, heating and numerous functional inadequacies. Excessive deferred maintenance and abuse, limited value-in-use, approaching abandonment or major reconstruction; reuse or change in occupancy is imminent. Effective age is near the end of the scale regardless of the actual chronological age.

2 = Fair- Badly worn. Much repair needed. Many items need refinishing or overhauling, deferred maintenance obvious, inadequate building utility and systems all shortening the life expectancy and increasing the effective age.

3 = Average- Some evidence of deferred maintenance and normal obsolescence with age in that a few minor repairs are needed, along with some refinishing. All major components still functional and contributing toward an extended life expectancy. Effective age and utility is standard for like properties of its class and usage.

4 = Good- No obvious maintenance required but neither is everything new. Appearance and utility are above the standard and the overall effective age will be lower than the typical property.

5= Very Good- All items well maintained, many having been overhauled and repaired as they have shown signs of wear, increasing the life expectancy and lowering the effective age with little deterioration or obsolescence evident with a high degree of utility.
     Represents the construction quality of improvements. Grades run from grade 1 to 13. Generally defined as:

1-3 Falls short of minimum building standards. Normally cabin or inferior structure.

4 Generally older, low quality construction. Does not meet code.

5 Low construction costs and workmanship. Small, simple design.

6 Lowest grade currently meeting building code. Low quality materials and simple designs.

7 Average grade of construction and design. Commonly seen in plats and older sub-divisions.

8 Just above average in construction and design. Usually better materials in both the exterior and interior finish work.

9 Better architectural design with extra interior and exterior design and quality.

10 Homes of this quality generally have high quality features. Finish work is better and more design quality is seen in the floor plans. Generally have a larger square footage.

11 Custom design and higher quality finish work with added amenities of solid woods, bathroom fixtures and more luxurious options.

12 Custom design and excellent builders. All materials are of the highest quality and all conveniences are present.

13 Generally custom designed and built. Mansion level. Large amount of highest quality cabinet work, wood trim, marble, entry ways etc.
     (1) The tendency of most kinds of data to cluster around some typical or central value, such as the mean, median, or mode.

(2) By extension, any or all such statistics.
     A market adjustment model which uses previous assessed value along with property characteristics. The basic model form is Sale Price = Prior Year Assessed Value * (1 / factor 0 + (factor1 * Char 1) + (factor2 * Char2).+(factorN*CharN) ), where Char1 and so on are items such as building grade, lot size and so forth. The influence of these characteristics must be statistically significant over and above any statistical relationship the prior year assessed value bears on sales prices.
     (1) In a mathematical expression, a number or letter preceding and multiplying another quantity. For example, in the expression, 5X, 5 is the coefficient of X, and in the expression aY, a is the coefficient of Y.

(2) A dimensionless statistic, useful as a measure of change or relationship; for example, correlation coefficient.
     The average deviation of a group of numbers from the median expressed as a percentage of the median. In ratio studies, the average percentage deviation from the median ratio. It is a measure of uniformity.
     A standard statistical measure of the relative dispersion of the sample data about the mean of the data; the standard deviation expressed as a percentage of the mean. It is a measure of uniformity.
     (1) Recently sold properties that are similar in important respects to a property being appraised. The sale price and the physical, functional, and locational characteristics of each of the properties are compared to those of the property being appraised in order to arrive at an estimate of value.

(2) By extension, the term "comparables" is sometimes used to refer to properties with rent or income patterns comparable to those of a property being appraised.
     For a given confidence level, the range within which one can conclude that a measure of the population (such as the median or mean appraisal ratio) lies.
     The required degree of confidence in a statistical test or confidence interval; commonly 90, 95, or 99 percent. A 95 percent confidence interval would mean, for example, that one can be 95 percent confident that the population measure (such as the median or mean appraisal ratio) falls in the indicated range. It is a measure of assessment reliability.
     A statistical phenomenon (and a technique for estimating its strength) whereby knowledge of one fact about a thing implies some knowledge of a second fact about that thing. For example, because the volume and weight of water are correlated, knowing that a quantity of water is one gallon also means knowing that its weight is eight and one-third pounds. Linear correlation, the kind most often encountered, means that an increase in one factor in some proportion (say, a doubling) changes the other in the same proportion. With curvilinear correlation, as between the radius and the area of a circle, this is not true, despite the fact that the correlation may be very strong in the sense that knowledge of one fact tells you precisely the other fact. These are examples of variables perfectly correlated or nearly so; more often, correlation is only partial - for example, the correlation between the age and height of a child. The correlation coefficient gives the strength of the linear relationship between the two variables.
     One of the three approaches to value, the cost approach is based on the principle of substitution - that a rational, informed purchaser would pay no more for a property than the cost of building an acceptable substitute with utility. The cost approach seeks to determine the replacement cost new of an improvement less depreciation plus land value.
     Information expressed in any of a number of ways. "Data" is the general term for masses of numbers, codes, and symbols generally, and "information" is the term for meaningful data. "Data" is the plural of datum, one element of data.
     The amount of a good or service that would be purchased at various prices during a given period.
     The degree to which data are distributed either tightly or loosely around a measure of central tendency. Measures of dispersion include the average deviation, coefficient of dispersion, coefficient of variation, range, and standard deviation.
     (1) An underlying characteristic of something (such as a house) that may contribute to the value of a variable (such as its sale price), but is observable only indirectly. For example, construction quality is a factor defined by workmanship, spacing of joists, and materials used. Factor definition and measurement may be done subjectively or by a computer-assisted statistical algorithm known as factor analysis.

(2) Loosely, any characteristic used in adjusting the sales prices of comparables.
     Is located in the last column of your search results. This column lets you know the total number of sales remaining after each search criteria was applied. You may need to modify the search criteria to return more sales or reduce the number of sales returned. Use the Filter Count as a guide for what search criteria to change.
     Classification by construction quality which refers to the types of materials used and the quality of workmanship. Buildings of better quality (higher grade) cost more to build per unit of measure and command higher value. (See Glossary in Area Report for Residential Building Grades in use by the King County Department of Assessments.)
     Anything done to raw land with the intention of increasing its value. A structure erected on the property constitutes one very common type of improvement, although other actions, such as those taken to improve drainage, are also improvements.
     Buildings, other structures, and attachments or annexations to land that are intended to remain so attached or annexed, such as sidewalks, trees, drives, tunnels, drains and sewers.
     The common or overall ratio of assessed values to market values.
     The date on which an obligation, such as a property tax bill (usually in an amount yet to be determined), attaches to a property and the property thus becomes security against its payment. The term is usually synonymous with appraisal date but is not necessarily so.
     A geographic area, typically encompassing a group of neighborhoods, defined on the basis that the properties within its boundaries are more or less equally subject to a set of one or more economic forces that largely determine the value of the properties in question.
     Market value is the major focus of most real property appraisal assignments. Both economic and legal definitions of market value have been developed and refined.
     The process of valuing a group of properties as of a given date, using standard methods, employing common data, and allowing for statistical testing.
     A mathematical expression of how supply and demand factors interact in a market.
     A measure of central tendency. The result of adding all the values of a variable and dividing by the number of values. For example, the mean of 3,5, and 10 is 18 divided by 3, or six. Also called arithmetic mean.
     A measure of central tendency. The value of the middle term in an uneven number of items arranged or arrayed according to size; the arithmetic average of the two central items in an even number of items similarly arranged; a positional average that is not affected by the size of extreme values. The median of 3,5, and 10 is 5. The middle number.
     (1) A representation of how something works.

(2) For purposes of appraisal, a representation (in words or an equation) that explains the relationship between value or estimated sale price and variables representing factors of supply and demand.
     The development of adjustments, or coefficients based on market analysis, that identifies specific factors with an actual effect on market value.
     The formal development of a model in a statement or equation, based on data analysis and appraisal theory.
     A theoretical distribution often approximated in real-world situations. It is symmetrical and bell-shaped; 68 percent of the observations occur within one standard deviation of the mean, and 95 percent within two standard deviations.
     One recording or occurrence of the value of a variable, for example, one sale ratio among a sample of sales ratios.
     At a minimum, an exterior observation of the property to determine whether there have been any changes in the physical characteristics that affect value. The property improvement record must be appropriately documented in accordance with the findings of the physical inspection. (Defined in WAC 458-07-015).
     All the items of interest, for example, all the properties in a jurisdiction or neighborhood; all the observations in a data set from which a sample may be drawn.
     Usually represents the current use of the property.
     The mean divided by the weighted mean. The statistic has a slight bias upward. Price-related differentials above 1.03 tend to indicate assessment-regressivity; price-related differentials below 0.98 tend to indicate assessment progressivity. It is a measure of assessment equity.
     (1) The maximum value of a sample, minus the minimum value. (2) The difference between the maximum and minimum values that a variable may assume.
     A study of the relationship between appraised or assessed values and market values. Indicators of market values may be either sales or independent "expert" appraisals. Of common interest in ratio studies are the level and uniformity of the appraisals or assessments. See also level of appraisal and level of assessment.
     In Washington the law states: "The term "real property" for the purposes of taxation shall be held and construed to mean and include the land itself, whether laid out in town lots or otherwise, and all buildings, structures or improvements or other fixtures of whatsoever kind thereon, except improvements upon lands the fee of which is still vested in the United States, or in the state of Washington, and all rights and privileges thereto belonging or in any wise appertaining, except leases of real property and leasehold interests therein for a term less than the life of the holder; and all substances in and under the same; all standing timber growing thereon, except standing timber owned separately from the ownership of the land upon which the same may stand or be growing; and all property which the law defines or the courts may interpret, declare and hold to be real property under the letter, spirit, intent and meaning of the law for the purposes of taxation. The term real property shall also include a mobile home which has substantially lost its identity as a mobile unit by virtue of its being permanently fixed in location upon land owned or leased by the owner of the mobile home and placed on a permanent foundation (posts or blocks) with fixed pipe connections with sewer, water, or other utilities: PROVIDED, That a mobile home located on land leased by the owner of the mobile home shall be subject to the personal property provisions of chapter 84.56 RCW and RCW 84.60.040." (RCW 84.04.090)
     (1) The period of time necessary for a jurisdiction to have a complete reappraisal. For example, a cycle of five years occurs when one-fifth of a jurisdiction is reappraised each year and also when a jurisdiction is reappraised all at once every five years. (2) The maximum interval between reappraisals as stated in laws.
     The phenomenon whereby knowledge of the value of one variable tells you something about the probable value of another. (See correlation). Relationships may be positive (an increase in the value of one variable implies an increase in the value of the other variable) or negative (a change in the value of one variable implies a change in the other direction for the value of the other variable). Independence of two variables means that there is no relationship between them.
     I n the cost approach, replacement cost new less physical incurable depreciation.
     The cost, including material, labor, and overhead, that would be incurred in constructing an improvement having the same utility to its owner as a subject improvement, without necessarily reproducing exactly any particular characteristics of the subject. The replacement cost concept implicitly eliminates all functional obsolescence from the value given; thus only physical depreciation and economic obsolescence need to be subtracted to obtain replacement cost new less depreciation (RCNLD).
     A sample of observations from a larger population of observations, such that statistics calculated from the sample can be expected to represent the characteristics of the population being studied.
     Each county assessor shall cause taxable real property to be physically inspected and valued at least once every six years in accordance with RCW 84.41.030, and in accordance with a plan filed with and approved by the department of revenue. Such revaluation plan shall provide that a reasonable portion of all taxable real property within a county shall be revalued and these newly-determined values placed on the assessment rolls each year. The department may approve a plan that provides that all property in the county be revalued every two years. If the revaluation plan provides for physical inspection at least once each four years, during the intervals between each physical inspection of real property, the valuation of such property may be adjusted to its current true and fair value, such adjustments to be based upon appropriate statistical data. If the revaluation plan provides for physical inspection less frequently than once each four years, during the intervals between each physical inspection of real property, the valuation of such property shall be adjusted to its current true and fair value, such adjustments to be made once each year and to be based upon appropriate statistical data. The assessor may require property owners to submit pertinent data respecting taxable property in their control including data respecting any sale or purchase of said property within the past five years, the cost and characteristics of any improvement on the property and other facts necessary for appraisal of the property.(RCW 84.41.041)
     Sales verification information that identifies something out of the ordinary on a sale.
     A set of observations selected from a population.
     The statistic calculated from a set of numbers by subtracting the mean from each value and squaring the remainders, adding together all the squares, dividing by the size of the sample less one, and taking the square root of the result. When the data are normally distributed, one can calculate the percentage of observations within any number of standard deviations from normal probability tables. When the data are not normally distributed, the standard deviation is less meaningful, and one should proceed cautiously.
     The standards of practice adopted by the department and governing real property appraisal activities by accredited appraisers are the generally accepted appraisal standards as evidenced by the current appraisal standards promulgated by the Appraisal Standards Board of the Appraisal Foundation. A complete text of these appraisal standards is available for viewing during normal working hours at the property tax division of the department (WAC 458-10-060).
     A smaller appraisal market in a geographical area. To limit your search to a sub area, you will need to know a parcel number that is in the geographical area of interest.
     The amount of a good or service that would be offered for sale at various prices during a given period.
     Properties are assessed as of January 1 of any given year for taxes paid the following year. For example, properties assessed in 2004 will pay taxes in 2005.
     Properties are assessed as of January 1 of any given year for taxes paid the following year. For example, properties assessed in 2015 will pay taxes in 2016.
     Total finished living space. This would include finished space in a basement.
     In Washington, all property must be valued and assessed at one hundred percent of true and fair value unless otherwise provided by law. "True and fair value" means market value and is the amount of money a buyer of property willing but not obligated to buy would pay a seller of property willing but not obligated to sell, taking into consideration all uses to which the property is adapted and might in reason be applied. (WAC 458-07-030 (1) ).
     Annual publication of the Appraisal Standards board of the Appraisal Foundation: "These Standards deal with the procedures to be followed in performing an appraisal, review or consulting service and the manner in which an appraisal, review or consulting service is communicated..STANDARD 6 sets forth criteria for the development and reporting of mass appraisals for ad valorem tax purposes or any other universe of properties" (p.1).
     The equality of the burden of taxation in the method of assessment.
     An item of observation that can assume various values, for example, square feet, sales prices, or sales ratios. Variables are commonly described using measures of central tendency and dispersion.
     Sum of the appraised values divided by the sum of the sales prices, which weights each value in proportion to its sale price. It is a better reflection of the sample than the arithmetic mean.
     An average in which each value is adjusted by a factor reflecting its relative importance in the whole before the values are summed and divided by their number.


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