Okla. Admin. Code § 710:10-3-2
The following words and terms, when used in this Subchapter, shall have the following meaning, unless the context clearly indicates otherwise:
"Aggregate assessment ratio" means the ratio of the total of assessed values to the total of the market-use values. This measure of central tendency may be distorted in that the ratio of a higher priced property will have a greater impact than the ratio of a lower priced property.
"Assessed value" means the fractional portion of market-use value against which ad valorem tax millage is levied. These statistics are obtained from the assessor's office.
"Average deviation" means the mathematical average of the total deviations and the total number of samples. This is a measure of dispersion or uniformity and deals with the inconsistency between individual ratios and the median or mean.
"Coefficient of dispersion" means the measure which shows the distribution of the individual ratios about the median. It is calculated by dividing the measure of dispersion (the average deviation) by the measure of central tendency (the median). The more uniform the assessments, the lower the coefficient of dispersion.
"Deviation from median" means the distance and direction of the individual assessment-ratio from the median.
"Market use related differential" means the measure calculated by dividing the mean assessment ratio by the aggregate assessment ratio and is used to indicate the direction of the bias of the mean assessment ratio and the aggregate assessment ratio. This measure shows any tendency for assessing relatively high priced properties higher or lower than relatively lower priced properties. A differential of more than 100 indicates lower ratios on the higher priced properties, while a differential of less than 100 indicates lower ratios on the lower priced properties. (Also known as the price-related differential)
"Market-use value" means the property value established by either the market or appraised value of the sample according to the actual use of the sample property.
"Mean assessment ratio" means a mathematical average of all the ratios and represents a measure of central tendency which is weighted.
"Median assessment ratio" means the ratio of the middle term. The median represents a measure of central tendency. The median, rather than the mean or aggregate ratio, is most often used in dispersion analysis.
"Ratio" means the ratio of assessed value to market-use value.
Okla. Admin. Code § 710:10-3-2