1. Field of the Invention
This application relates generally to computer implemented analysis of price appraisal data. More specifically, the application relates to a system and method for performing computer implemented analysis and scoring of real estate appraisal adjustment data.
2. Description of the Related Art
The sales comparison approach is the primary valuation method used for most residential appraisals in the United States. This approach is based on the assumption that home purchasers will pay no more for a property than it would cost to purchase a comparable substitute property. Because it is rare to find two identical houses for sale at the same time in the same neighborhood, appraisers typically select comparable sales (“comps”) that vary from the subject property on a variety of factors, and then account for the differences using a formal adjustment process. The resulting opinion of subject property market value should represent the appraiser's professional conclusion, based on market data, logical analysis, and judgment.
First, the appraiser documents facts about the subject property and obtains facts about the recent sales of other properties in the local market. From these facts, the appraiser identifies the comps by determining which property characteristics drive value in the subject property's market and selecting the properties that are most similar to the subject property in these respects. In addition to physical property characteristics, recency of sale and geographical proximity are key factors in determining similarity.
Next, the appraiser calculates dollar-value adjustments for differences in property characteristics between each comp and the subject. For each feature where the comp is inferior to the subject property, the appraiser adds value to the sale price of the comp. For each feature where the comp is superior, the appraiser subtracts value. The end result of all adjustments should equal the market value of the subject property. The appraiser then reconciles the adjusted value of the various comps and calculates the appraisal value of the subject property by determining an appropriate weighted average for the values of the adjusted comps.
Many appraisers, however, tend to under-adjust in their appraisals. Specifically, appraisers routinely select as comps properties having superior property characteristics but then fail to subtract an appropriate amount for the comps' advantages. Because of this, the practice of comp selection itself leads to adjustments that can artificially inflate the appraised value of a subject property. Furthermore, because appraisers routinely attempt to create the best impression of a subject property, the set of comps that they select and the adjustments that they make can create false and inflated value.
In this manner, when an appraiser is motivated to inflate the value of a subject property, he or she may ignore good comps close to the subject property that have low sale prices. Instead, the appraiser may select comps that are superior to the subject property because, for example, they are of a newer construction, are closer to desired neighborhood amenities, or are located in better school districts. The value of the subject property will then be inflated if the appraiser simply makes smaller-than-warranted downward adjustments to account for the differences.
Accordingly, there is a need for a system and method to rate the quality of the adjustments made by appraisers in their appraisals of real property. Furthermore, there is a need for a system and method for detecting and quantifying adjustment issues found in an appraisal.
In one example, this application describes a system and method of evaluating risk in the adjustment of the comps in real estate appraisals. Using algorithmic modeling, various embodiments evaluate an appraiser's claims against industry standards, model predictions, and geographic information service (GIS) analysis, etc. Various embodiments detect erroneous adjustments because they are both materially different from a model estimate and materially different than those made by the majority of appraisers in the same area.
According to one embodiment, the scoring of appraisal adjustments rates the quality of adjustments made by appraisers in their appraisals of real property. This is done by accessing a model adjustment database that is based on an automated valuation model and a peer adjustment database that is based on an aggregate measure of appraiser peers in the same geographic location as the subject property. A comparison is conducted for adjustments made by the appraiser to both model adjustments and peer adjustments to determine discrepancies. When a discrepancy is larger than a threshold, a message or warning may be generated. A comparable sales pool composition database is also accessed to determine a valuation impact of the adjustments made on the particular set of comparable sales selected by the appraiser. After data evaluation, an adjustment rating score is calculated for the property appraisal based on the number and severity of messages and the valuation impact.
This application can be embodied in various forms, including business processes, computer-implemented methods, computer program products, computer systems and networks, user interfaces, application programming interfaces, and the like. The foregoing summary is intended solely to give a general idea of various aspects of this application, and does not limit the scope of the application in any way.
These and other more detailed and specific features of various embodiments are more fully disclosed in the following description, reference being had to the accompanying drawings, in which:
In the following description, numerous details are set forth, such as flowcharts, data tables, and system configurations. It will be apparent to one skilled in the art that these specific details are merely exemplary and not intended to limit the scope of this application.
Systems and methods are disclosed that provide parties to a real estate transaction with the means to evaluate risk in the adjustments of comparable sales (“comps”) used in real estate appraisals. Although discussed herein in the context of real estate appraisals, it should be understood that the systems and methods herein disclosed are not limited to real estate appraisals, but have application with respect to other types of appraisals and valuation judgments.
[Subject Appraisal Adjustments]
In evaluating a property appraisal, various embodiments may utilize an appraiser adjustment database having entries corresponding to respective property characteristics as determined by an appraiser of a subject property. For example, the database may include entries respectively detailing a property characteristic, a value for the property characteristic corresponding to the subject property, a value for the property characteristic corresponding to the comp, and the value of the adjustment made by the appraiser to account for any discrepancy between the subject property and the comp.
As noted above, as part of the adjustment process, the appraiser must weigh the differences between a subject property and one or more comps. The appraiser chooses comps in a given neighborhood that are most similar to the subject in terms of the characteristics and amenities that drive value in the local market and, for characteristics that are not close or identical, makes appropriate value adjustments to the sale price of the comps to account for the differences.
Form 100 may be a paper form that the appraiser fills out by hand or an electronic form that the appraiser fills out electronically.
In the illustrated example, the property characteristics 131 include sale date, gross living area (GLA), lot size, exterior, quality of construction, age, condition, number of bedrooms, number of bathrooms, presence or absence of a basement, and presence or absence of a garage. Form 100 may, however, have more, fewer, or different property characteristics as desired. Although the particular property characteristics 131 shown in
Property characteristics 131 may be those found in a Uniform Appraisal Report; for example, proximity to subject, sale price, sale price per GLA, financing concessions, date of sale, location, sale type (i.e., leasehold or fee simple), lot size, view, design (i.e., style), quality of construction, actual age, condition, above grade room count, GLA, finished rooms below grade, functional utility, HVAC, energy efficient items, garage, patio, fireplace, and the like.
For each property characteristic 131, the appraiser enters a value corresponding to the subject property in subject column 110, and values corresponding to the comps in respective comp columns 120. In
The adjustments made by the appraiser on form 100 are preferably in a machine-readable form and the adjustments may be entered into a database. In instances where form 100 is a paper form, the adjustments may be hand coded or electronically coded by a technology such as optical character recognition (OCR). In instances where form 100 is an electronic form, the adjustments may preferably be automatically electronically coded.
[Model Adjustments]
Furthermore, in evaluating a property appraisal, various aspects may utilize a model adjustment database having entries corresponding to expected values of the respective property characteristics as determined by an automated valuation model.
Statistical analysis is performed on housing data to determine the marginal values of particular property characteristics. The results of the statistical analysis (which may be the estimated coefficients of a regression-based model) are entered and stored in a database for future access. Because the computerized model is based on a statistical analysis, the results will typically be more reliable when a larger amount of input data is included.
The computerized model is preferably a regression model. Most preferably, the regression model is a hedonic regression model. In any event, the computerized model determines an expected market price placed on the individual characteristics of a home. At least some of the individual characteristics may correspond to property characteristics 131 described above with reference to
An exemplary computerized model operates using the statistical method of linear regression in a logarithmic scale. In such a method, the expected price may be modeled as:
where P represents the expected price, α0 is a constant term, xi represents the value of an individual property characteristic, αi represents a coefficient representative of the weight assigned to the corresponding characteristic, and β represents the base of the logarithm. In a regression model, the coefficients αi are calculated so as to minimize the sum of the squared errors. Here, because the price varies as the log base β of the property characteristic, a concept of diminishing returns may be incorporated. For example, a relative increase of 100 ft2 of GLA will have a larger impact on the price of a house with a GLA of 1000 ft2 than on the price of a house with a GLA of 5000 ft2.
In the illustrated example, the continuous variables are GLA, lot size, age, number of bedrooms, and number of bathrooms. The continuous variables, however, may include any property characteristic capable of being represented as a continuous variable. Furthermore, an automated valuation model may utilize fewer or differently defined continuous variables if desired. In coefficient column 220 corresponding to the continuous variables, a negative number represents a decrease in price with an increase in the value of the corresponding property characteristic, whereas a positive number represents an increase in price with an increase in the value of the corresponding property characteristic.
According to
In the illustrated example, the dummy variables are brick/stone exterior, vinyl exterior, excellent construction, fair construction, excellent condition, fair condition, basement, and garage. The dummy variables, however, may include any property characteristic capable of being represented as either 1 or 0. Furthermore, an automated valuation model may utilize fewer or different dummy variables if desired. Of course, because the dummy variables take only one of two possible values, these particular entries may be represented by a linear regression in a linear scale. As such, in coefficient column 220 corresponding to the dummy variables, a negative number represents a decrease in price when the corresponding property characteristic is present, whereas a positive number represents an increase in price with an increase in the value of the corresponding property characteristic.
According to
Although the model adjustments described above have been explained in the context of a linear regression in a log scale, one skilled in the art would recognize that model may be based on a linear regression in log-log scale, a linear regression in a linear scale, a nonlinear regression, combinations thereof, or any other statistical prediction method.
[Peer Adjustments]
Furthermore, in evaluating a property appraisal, various aspects may utilize a peer adjustment database having entries corresponding to aggregate values of respective property characteristics as determined by appraiser peers in the same geographic location as the subject property.
Preferably, a large number of appraisal forms of the type described with reference to
In the illustrated example, the data table 400 contains columns corresponding to gross living area. The data table 400 may also include differential, adjustment, and valuation columns corresponding to one or more additional property characteristics in the same table. Alternatively, the peer adjustment database may include a separate data table for each property characteristic.
In the illustrated example, the statistical distribution is a positively-skewed normal distribution. However, because the statistical distribution is based on actual data, it is not limited to any particular distribution.
In a first example, appraisal adjustment scoring comprises operations that identify unreasonable adjustments and rates the overall quality of an appraiser's adjustments in a subject appraisal.
In the first example, the entire spectrum of adjustment errors and misrepresentations made by appraisers are examined by performing three unique evaluations of appraiser adjustments.
One such evaluation is a comparison of the adjustments made in a subject appraisal to those made by an automated valuation model. The computerized model may preferably be the model described above with reference to
A second such evaluation is a comparison of the adjustments made in the subject appraisal to those made in aggregate on other appraisals by appraiser peers who work in the same geographic location. The aggregate data may preferably be represented by the database described above with reference to
A third such evaluation is an examination of the composition of the comp pool chosen by the appraiser to determine the valuation impact of questionable or nonstandard adjustments on the appraiser's price opinion of the subject property.
Where the operations illustrated in
The exemplary method is initialized at step S100. The exemplary method then proceeds to step S110 and loads the subject appraisal data. The data accessed in step S110 may correspond to a single property characteristic and associated adjustment, a subset of all property characteristics and associated adjustments, or all property characteristics and associated adjustments.
The exemplary method then performs the above unique evaluations in steps S120, S130, and S150 for the accessed data. Steps S120, S130, and S150 may be performed in series, in parallel, or in a combination of series and parallel. In step S120, the exemplary method performs a comparison between the appraiser adjustment value and a corresponding model adjustment value by performing a series of subprocesses described in more detail below. In step S130, the exemplary method performs a comparison between the appraiser adjustment value and a corresponding peer adjustment distribution by performing a series of subprocesses also described in more detail below. In step S150, the exemplary method performs an analysis of the chosen sales pool also described in more detail below.
The exemplary submethod is initialized at step S120 as shown with reference to
In step S125, the exemplary submethod flags the property characteristic identifier. In step S126, the exemplary submethod notes the magnitude of the appraiser-model discrepancy. Although
In step S127, the exemplary submethod determines if all desired property characteristics have been analyzed. If there are still more property characteristics to analyze, the exemplary submethod returns to step S121 and loads a new property characteristic identifier. If there are no additional property characteristics to analyze, the exemplary submethod is terminated in step S128, and the exemplary method proceeds to step S140 as shown in
The exemplary submethod is initialized at step S130 as shown with reference to
In step S135, the exemplary submethod flags the property characteristic identifier. In step S136, the exemplary submethod notes the magnitude of the discrepancy. Although
In step S137, the exemplary submethod determines if all desired property characteristics have been analyzed. If there are still more property characteristics to analyze, the exemplary submethod returns to step S131 and loads a new property characteristic identifier. If there are no additional property characteristics to analyze, the exemplary submethod is terminated in step S138, and the exemplary method proceeds to step S140 as shown in
The exemplary submethods illustrated in
In step S150 illustrated in
For example, if the exemplary method determines that all of the comps chosen by the appraiser are very similar to the subject property, the exemplary method may determine that any adjustment errors in the appraiser adjustment are likely to have small impact on the appraisal. On the other hand, if the exemplary method determines that some or all of the comps chosen by the appraiser are very dissimilar to the subject property, the exemplary method may flag the dissimilar comps and determine that any adjustment errors in the appraiser adjustment are likely to have a severe impact on the appraisal. In this manner, the exemplary method may detect situations where the comp pool is skewed to the superior (for example, larger GLA) side and the downward adjustments are inadequate, or where the comp pool is skewed to the inferior side and the upward adjustments are inadequate.
In step S140, the exemplary method determines if certain conditions have been met in steps S120, S130, and/or S150, and generates messages that indicate the adjustment dimension in question and the conditions that were violated. The conditions may be predetermined or dynamically calculated, and may vary according to associated property characteristics. Although
For example, the exemplary method may generate a first message when comps skew large or small relative to the subject property and when the appraiser's GLA adjustment is an outlier compared to both peers and model for a particular property characteristic. In other words, the first message may indicate that the adjustment error is large compared to both the model adjustment and the peer adjustment, and that the adjustment error is likely to have a severe impact on the appraisal.
Furthermore, the exemplary method may generate a second message when the appraiser's net adjustment for a particular comp based on all relevant property characteristics differs from the net model adjustment by a particular amount; for example, by 20% or more. In other words, the second message may indicate that even if the adjustment error is small, any adjustment error is likely to have a disproportionately large impact on the appraisal.
Although only two messages have been explicitly described, the exemplary method may generate more than two different types of messages based on a given set of messaging rules. Furthermore, multiple messages may be generated for a single comp and/or a single property characteristic.
In step S160, the exemplary method assigns a single overall adjustment rating based upon the combination and severity of messages generated in step S140. The exemplary method may rate the appraiser's adjustments on an ordinal scale, for example from one to five. In this example, a lower rating score indicates no or few adjustment risks, and a higher rating score indicates increasingly significant problems that increase the risk of valuation misrepresentation. The exemplary method may calculate the rating based on a predetermined or dynamically calculated scoring table.
In an exemplary method using scoring table 900, a plurality of penalty points are assigned based on the degree of difference in the appraiser adjustment as compared with the model and peers. In this example, an appraisal adjustment that is in the second percentile compared with peers and is less than ten percent of the model adjustment receives five points. The amount of penalty points decreases as the adjustment as a percentile of peers and/or as a percentage of model becomes closer to the mean or median. In other words, larger deviations from the model in combination with an appraiser adjustment being farther out in the peer distribution tail will result in a larger penalty than a smaller deviation from the model combined with the appraiser adjustment being closer to the peer distribution mean or median. In this manner, the total amount of penalty points is indicative of both an appraiser-peer discrepancy and an appraiser-model discrepancy.
While one exemplary scoring table 900 has been provided for illustration, in practice any particular scoring method may be utilized so long as the scoring method quantifies the concepts wherein: (a) larger deviations from peers and model jointly will result in larger penalties for each individual adjustment; (b) the appraised value of the subject property is deemed less reliable the more individual adjustments are flagged by the exemplary method; and (c) bad adjustments made on a comp pool that is heavily skewed to one side of the subject property are deemed more likely to have a material impact on the overall appraised value of the subject property.
After step S160 has been completed, the exemplary method proceeds to step S170 as illustrated in
After step S170 has been completed, the exemplary method may terminate at step S180. In other aspects, the exemplary method may proceed from step S180 back to step S100 to repeat steps S110-S170 for one or a plurality of additional property characteristics.
In a second example, appraisal adjustments scoring comprises a computing device that identifies unreasonable adjustments and rates the overall quality of an appraiser's adjustments in a subject appraisal.
The appraiser adjustment value accessing module 1071 may be configured to access an appraiser adjustment value corresponding to a value of a respective property characteristic of a subject property as determined by an appraiser of the subject property. The model adjustment value accessing module 1072 may be configured to access a model adjustment value corresponding to an expected value of the respective property characteristic as determined by an automated valuation module. The peer adjustment distribution accessing module 1073 may be configured to access a peer adjustment distribution corresponding to an aggregate value of the respective property characteristic as determined by appraiser peers. The appraiser adjustment value, model adjustment value, and peer adjustment distribution may be located in a database. Alternatively, the appraiser adjustment value, model adjustment value, and peer adjustment distribution may be located in separate databases.
The appraiser-model discrepancy module 1074 may be configured to determine an appraiser-model discrepancy when a difference between the appraiser adjustment value and the model adjustment value exceeds a first threshold. The appraiser-peer discrepancy module 1075 may be configured to determine an appraiser-peer discrepancy when the difference between the appraiser adjustment value and the peer adjustment distribution exceeds a second threshold.
The appraiser-model discrepancy module 1074 and the appraiser-peer discrepancy module 1075 may be configured to perform operations in parallel; for example, as shown in
The message generating module 1076 may be configured to generate a respective adjustment message when a condition is met during the steps of determining, the adjustment message indicating the respective property characteristic and the condition.
The sales pool impact determining module 1077 may be configured to access a sales pool composition data corresponding to comparable sales as determined by the appraiser. The sale spool impact determining module 1077 may be further configured to determine a valuation impact of the sales pool composition data on the respective appraiser adjustment value.
The rating module 1078 may be configured to assign a rating to the property appraisal, the rating being based upon the number and severity of the adjustment messages and the valuation impact.
The databases described above may be stored in the memory 1060, in the external computer program product, or in a remote device, and may be accessed by the computing device 1000 via the internal bus 1040 or via the communication unit 1030 connected to, for example, a network.
In a third example, appraisal adjustments scoring comprises a computer system that identifies unreasonable adjustments and rates the overall quality of an appraiser's adjustments in a subject appraisal.
The operations may be stored entirely in a memory of one of the computing devices 1110-1130, for example the server computing device 1120. In such a configuration, the operations may be accessed by terminal computing devices 1110, 1130 via the network connection. Thereby, the terminal computing devices 1110, 1130 may execute the operations by accessing the program code stored on the server computing device 1120.
Alternatively, the operations may be stored in a distributed manner across more than one computing device 1110-1130. In such a configuration, portions of the operations may be accessed by terminal computing devices 1110, 1130 via a network connection and other portions of the operations may be accessed by terminal computing devices 1110, 1130 from their respective internal memories. Thereby, a user may execute a user interface portion of the operations via a terminal computing device 1110, causing the terminal computing device 1110 to communicate with the server computing device 1120. In response, the server computing device 1120 may execute appropriate portions of the operations and communicate data generated therein to the terminal computing device 1110 for storage, display, or further analysis. In an alternate configuration, respective portions of the operations may be performed by a plurality of computing devices in a distributed manner, for example by distributed parallel computing.
Although the example of
Computing devices such as the computing devices 1000, 1110-1130, 1210, and 1230-1240 may generally include computer-executable instructions such as the instructions to perform the operations, where the instructions may be executable by one or more computing devices such as those listed above. Computer-executable instructions may be compiled or interpreted from computing programs created using a variety of programming languages and/or technologies, including but not limited to Java™, C, C++, FORTRAN, Visual Basic, PERL, etc., and combinations thereof. Generally, a processor, for example, a microprocessor, receives instructions from, for example, a memory, a computer-readable medium, etc., and executes these instructions, thereby performing one or more processes, including one or more of the processes or subprocesses described herein. Such instructions and other data may be stored and transmitted using a variety of computer-readable media.
It is understood that as used herein, a processor may “perform” or “execute” a particular function by issuing the appropriate commands to other units, such as other components of the computing device, peripheral devices linked to the computing device, or other computing devices. As such, the commands may cause other units to take certain actions related to the function. For example, although a processor does not display an image in the sense of the processor itself physically emitting light in a pattern, the processor may nonetheless “execute” the function of “displaying” an image by issuing the appropriate commands to a display device that would then emit light in the requisite pattern. In this example, the display device that the processor causes to display the image may be part of the computing device that includes the processor, or may be connected remotely to the computing device that includes the processor by way of, for example, a network. In this manner, a processor included in a server hosting a webpage may “display” an image by issuing commands via the Internet to a remote computing device, the commands being such as would cause the remote computing device to display the image. Moreover, for the processor to have “executed” the particular function, the generation of a command that would cause another unit to perform the various actions of the function is sufficient, whether or not the other unit actually completes the actions.
A computer-readable medium described herein includes any non-transitory (tangible) medium that participates in providing data, such as instructions, that may be read by a computer. Such a medium may take a variety of forms, including but not limited to volatile media such as random access memory (RAM) or non-volatile media such as optical or magnetic disks. Such instructions may be transmitted via one or more transmission media, including coaxial cables, copper wire, and fiber optics, including the wires that comprise a system bus coupled to a processor of a computer. Common forms of computer-readable media include, for example, a floppy disk, a hard disk, magnetic tape, a CD-ROM, a DVD-ROM, punch cards, paper tape, RAM, flash memory, or any other medium from which a computer can read.
Databases, data repositories, data tables, or other data stores described herein may include various kinds of mechanisms for storing, accessing, and retrieving various kinds of data, including a hierarchical database, a set of files in a system, an application database in a proprietary format, a relational database management system (RDBMS), etc., or combinations thereof. Each such data store is typically included within a computing device employing a computer operating system such as those mentioned above, and are accessed via a network in a variety of manners. A file system may be accessible from a computer operating system, and may include files stored in various formats. An RDBMS generally employs the Structured Query Language (SQL) in addition to a language for creating, storing, editing, and executing stored procedures, such as the PL/SQL language mentioned above.
The automation of adjustment scoring is a new step in appraisal evaluation that has never been accomplished before at this level of detail and with this comprehensive a database of appraisal data. The rating operations, based on messaging, allows for a level of granularity previously unseen in appraisal evaluation and analysis. Furthermore, by evaluating an appraisal in comparison both to a model and to peers while simultaneously evaluating the composition of the pool of comparable sales, various embodiments accurately identify only those adjustments most likely to impact value.
With regard to the processes, systems, methods, submethods, algorithms, operations, etc., described herein, it should be understood that, although the steps of such operations have been described as occurring in a certain ordered sequence, such operations could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps may be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. In other words, the descriptions of operations herein are provided for the purpose of illustrating certain aspects of the application, and should not be construed so as to limit the scope of the application.
Accordingly, it is to be understood that the above description is intended to be illustrative and not restrictive or exhaustive. Although various aspects been described in considerable detail with reference to certain aspects thereof, the invention may be variously embodied without departing from the spirit or the scope of the invention. Therefore, many aspects and applications other than the specific examples provided herein would be apparent upon reading of the above description. It is anticipated and intended that future developments will occur in the technologies discussed herein, and that the disclosed systems and methods will be incorporated into such future embodiments. In other words, it should be understood that the application is capable of modification and variation.