Display apparatus

A display for presenting trends in financial commodities such as stocks. The display is made up of an array of rectangular boxes each representing an individual stock. Each display is dedicated to a different sector of the market. The color of the individual boxes is representative of the degree of fractional deviation of the most recent trading price of that stock from an assigned selected reference value, e.g., the price at the end of the previous trading session. Preferably, the location of each individual stock within the display is determined by the degree of influence that the user is to perceive that stock has upon one characteristic of the market, e.g., the volatility on one axis and perceived source of volatility on another axis, or the stocks can be located in accordance with decreasing market share on one axis and decreasing capitalization on the other. The result is a color display in which the current behavior of stock prices with respect to a selective set of reference stock prices in a selected sector of the economy is summarized in a checkerboard-like collection of visual boxes whose individual colors show the current trend in trading prices. The overall display shows sector trends and those individual stocks deviating from those trends. The individual boxes can also be designed to show trend information about the stocks that they respectively represent.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 This invention relates in general to display apparatus presenting a
 comparison of analogous components not linked by a definable physical
 relationship from which one component could be extrapolated from another,
 and more particularly to apparatus for displaying trends in a process
 related to financial markets, having a number of analogous components each
 having a corresponding, variable element.
 2. Background Information
 The trading of financial instruments such as stocks and bonds has largely
 become a computer supported operation. Almost all significant trading of
 securities is accomplished by computer pursuant to the established
 protocols of the major exchanges. For example, on the New York Stock
 Exchange, orders for specific securities are entered at a terminal
 operated by a licensed agent with a "seat" on the exchange. This order is
 processed through a stock "specialist", a firm that is obligated to manage
 transactions for a given security. The specialist clears the stock trade
 at a price reflecting the current supply-demand environment for that
 security. Upon confirmation of the trade, the parties up-date their
 respective positions via computer controlled memory. For the most part,
 the above transaction is accomplished through computer terminals linked
 together by communication buses or telephone lines.
 A different arrangement is provided for certain over the counter trading
 associations of which NASDAQ "National Association of Securities Dealers"
 is probably the most prominent. These exchanges avoid the use of
 specialists in specific stocks and membership does not invoke a seat on an
 exchange. To the contrary, NASDAQ is established as a computer integrated
 market of select securities, wherein members trade as agents for their
 customers and make markets in specific securities themselves. To operate
 effectively in this environment the members must have a sophisticated
 communication system that permits entry and up-dating of current stock
 positions supporting the desired transactions. This invokes the creation
 and operation of a central on-line database for the securities to be
 transacted. Members enter into the NASDAQ database via a remote terminal
 and input their request as more fully described in U.S. Pat. No. 5,297,032
 issued Mar. 22, 1994.
 These operations are heavily dependent on appropriately programmed computer
 systems, for example, see U.S. Pat. No. 4,674,044 to Kalmus et al., titled
 "Automated Securities Trading System". In addition to supporting such
 transactions, dealers also participate in making markets in individual
 securities, i.e., the dealer is also the principal and sells the
 securities out of dealer inventory.
 The above operations are performed in real time with the participation of
 hundreds of competing buyers and sellers forming a highly competitive
 environment. A central element to success in such a market is the rapid
 access to vital information on current market conditions in terms of
 market trends and recent swings to support the ability to enter quickly to
 establish or withdraw a price. For example, a trend away from a given
 security is first indicated by a drop of market makers on the inside
 market. Participants with an early indication of the soaring market are in
 the best position to profit from it, "or reduce their exposure".
 This process has become more complicated with customers communicating with
 their traders on-line directly through the use of personal computers. In
 order for such customers to maximize the benefits of their trades it is
 imperative that they have the ability to assimilate the vital information
 available on current market conditions in real time. Many of those
 customers are substantially less sophisticated than their traders and need
 to have that information presented in a user friendly manner that they can
 readily adsorb, understand and apply.
 In the past, the traders were largely dependent on information supplied
 directly from the database of transactions in a form selected primarily
 for ease of communication. Although the on-line data was rich with current
 market information, the form of this data simply was not optimized to
 permit rapid extraction and review to support trading; to the contrary,
 the feed data was mostly devoid of trend information in the market and the
 traders had to mostly rely on intuition and luck in predicting market
 shifts.
 U.S. Pat. No. 5,297,032, cited above, addressed this issue by providing a
 multi-tasking workstation that includes seven primary applications each of
 which is set in a windowed interface for implementing a plurality of
 security based transactional operations. While the invention provided more
 information, including trends, to the operators, it presented a different
 problem in contributing to information overload and the lack of ease of
 assimilation of the information. The depth of this problem is described
 more fully in U.S. Pat. No. 4,816,208, entitled "Alarm Management System",
 issued Mar. 28, 1989. Accordingly, it is an objective of this invention to
 establish a display format which will communicate multiple facets of
 information about the markets in a form that is easily absorbed and
 readily understood. More particularly, it is an object of this invention
 to provide such a display for identifying trends that is applicable to a
 number of processes having a plurality of analogous components with a
 common variable element.
 SUMMARY OF THE INVENTION
 It is an object of this invention to provide a display for identifying
 trends in a process including a number of analogous components each having
 at least one corresponding, variable element that enables a display
 operator to readily assimilate and easily understand the trends and the
 corresponding information from which they are generated. In this regard, a
 plurality of complementary geometrically shaped fields, e.g., rectangles,
 each representative of the corresponding, variable element of one of the
 components, are displayed side by side in a graphical array. A visual
 pattern within each field is varied according to a common code which
 incrementally changes between two extremes; the displayed pattern
 corresponding to the last measured variation of the variable element from
 an intermediate reference value. The reference value is the measured
 empirical value of the corresponding variable element for each component
 chosen at a predetermined, common point in time and the extremes are
 common preselected deviations.
 In a preferred embodiment the invention is directed to determining trends
 in financial markets and more particularly in stock markets. The display
 is rectangular with boxes within the display each representing an
 individual stock. Each display is dedicated to a different sector of the
 market. The color of the individual boxes is representative of the degree
 of fractional deviation of the most recent trading price of that stock
 from an assigned selected reference value, e.g., the price at the end of
 the previous trading session or the beginning of the current week, month
 or year. Preferably, the location of an individual stock within the
 display is determined by its volatility in the market, e.g., apparent
 sensitivity to broad changes in the market on one axis and apparent
 sensitivity to changes external to the market on the other axis, or stocks
 can be located in accordance with decreasing market share on one axis and
 decreasing capitalization on the other.
 In the foregoing embodiment, the fractional deviation values for the
 various stocks are translated into colors for presentation on the display.
 The result is a color display in which current behavior of stock prices
 with respect to a selected set of reference stock prices in a selected
 sector of the economy is summarized in a checkerboard-like collection of
 visual boxes whose individual colors show the current trends in trading
 prices of the corresponding stock. Broad shifts or trends in stock prices
 in the sector appear as broad areas of a single color or of adjacent
 colors. The deviation of individual stocks from the trend can also be
 observed. With the position of the representations of individual stocks
 ordered as set forth above, the upper left corner of the display is most
 representative of the trend of the sector since the most influential
 stocks are located there.
 A modification of this general pattern could be implemented in accordance
 with this invention in the special case in which trading in one or more
 stocks on a given stock exchange is halted by that exchange in response to
 the development of abnormal conditions relating to that stock or those
 stocks. In this special case the box/block corresponding to each affected
 stock would be assigned a unique color lying outside the set of colors
 normally used to indicate degrees of fractional deviation of current
 trading prices from reference values.
 In another embodiment of the invention, a smoothing algorithm is applied to
 the raw fractional deviation values. This results in a smoothened display
 which emphasizes the overall trend of the sector. In another enhancement
 each box representative of a stock is broken down into a plurality of
 fields from which a change in the trend of the individual stocks or other
 market components over a preselected time period can be observed. The
 invention can be applied to other financial markets as well such as the
 currency markets.

DESCRIPTION OF THE PREFERRED EMBODIMENTS
 The present invention is directed to display generation apparatus for
 displaying to a user a comprehensive indication of ongoing changes and
 trends in a process having analogous components with varying corresponding
 elements. Each component is represented by a field in an array with the
 status of the element for each component relative to a reference value
 shown by a color code in the corresponding field, with the variation in
 colors across the display identifying trends.
 The invention can be better understood when viewed in a particular
 application to the financial markets and in particular, in one preferred
 embodiment, to stock markets. The invention in such an application
 comprises a display generation apparatus for portraying to a user a
 comprehensive indication of ongoing changes and trends in trading prices
 of a number of individual corporate stocks such as are traded on a
 recognized stock exchange, e.g., the New York Stock Exchange. The
 invention further provides a display for translating information relating
 to the most recent trading prices of such stocks as determined from a
 currently available, on-line data source, such as described in U.S. Pat.
 No. 5,297,032, into coded colors displayed by individual pixels on the
 electronic output screen of the display apparatus.
 Desirably, the set of stocks whose trading price fluctuations are depicted
 in a specific display is selected to be representative of a particular
 sector of the national economy. Thus, one such display might be indicative
 of the trends in trading prices of stocks issued by corporations active
 primarily in the "services" sector. Another display of the same basic
 arrangement can represent trends in trading prices of stocks of companies
 involved primarily in the "energy" sector, etc. It is expected that the
 total number of displays, corresponding, respectively, to the several
 sectors of the economy as defined in a given stock exchange will be about
 twelve, though that should not be considered a limitation of this
 invention.
 While the fully expanded implementation of the invention is envisioned to
 treat, effectively in parallel, all of the identified sectors of the
 economy as perceived in a specific stock exchange, for purposes of
 simplification the processing of stock transaction information in a single
 sector is described here. Generalization to parallel processing of
 information relevant to more than one sector is straightforward. However,
 certain display aspects of a multi-sector parallel processor will be noted
 in the following description.
 As shown in FIG. 1, the basic display arrangement 62 for a given sector
 consists of a square or rectangular array of "boxes" 60 of square or
 rectangular form arranged in a regular row and column configuration. Each
 "box" area or field 60 consists of a number of addressable pixels, also
 arranged in rows and columns, on the output display screen and corresponds
 to a specified stock in the sector of interest. Though not shown in FIG.
 1, the field/stock correspondence for each box is shown within the area of
 the box by an alphabetic indication of the name of the corporation issuing
 the stock. The alphabetic indication should be a contrasting color to
 enhance readability. Alternatively, it is possible by means of a mouse,
 touch screen, or light pen for a user to call up the name of the issuing
 corporation together with details of the past performance for example, on
 request.
 The color of the area on the display screen enclosed by each box 60 is
 representative, by a programmed code, of the degree of fractional
 deviation of the most recent trading price of the corresponding stock from
 an assigned, selectable reference value of the trading price of that
 stock. The reference value of a trading price of a given stock could be,
 for example, the closing price of that stock at the end of the previous
 trading session or the opening price of that stock at the first trading
 session of the current week, month or year. Alternative reference values
 are also accommodated. However, to be meaningful the reference values of
 all considered stocks in the sector of interest must correspond to the
 same point in time.
 The association of a given box 60 on the display 62 with a given stock in
 the corresponding sector is, in principle, arbitrary. However, several
 different association patterns can provide added meaning to the display,
 making trends more recognizable. In one, stocks are assigned to box
 locations in terms of "volatility" of the stock prices and of perceived
 sources of volatility. Thus, an overall arrangement of a typical sector
 display can be depicted as illustrated in FIG. 1 in which the left to
 right aspect of the display can be representative of increasing
 sensitivity to internal sector/market activity while the top to bottom
 aspect of the display is representative of increasing sensitivity to
 external activity. In this approach sensitivity to internal market
 activity can be measured in terms of the value of the "Beta" parameter
 quoted in reviews of the behavior of individual stocks. Beta is a
 parameter that identifies how volatile the stock is when compared to a
 particular index. More information about the Beta parameter as an estimate
 of risk can be found in a reference authored by Malkiel, entitled A Random
 Walk Down Wall Street. After reviewing that reference it will be
 appreciated that the horizontal aspect of FIG. 1 can readily represent
 "systematic risk" and the vertical aspect can represent "unsystematic
 risk" as such terms are defined in the reference.
 Alternatively, the overall assignment of stocks to boxes 60 in a given
 sector display 62 can be in terms of total capitalization and market
 share. For example, the top to bottom aspect of FIG. 1 can be
 representative of decreasing market share while the left to right aspect
 is representative of decreasing capitalization. While the individual
 fields 60 for the respective stocks have been described as boxes, it
 should be appreciated that they can take on other geometric forms, e.g.,
 triangles. Desirably the mating interfaces between fields should form a
 complementary design so that the transition from one to the other is
 smooth.
 As a general rule, the most stable and most indicative stocks in a given
 sector should be assigned box locations in the upper left region of the
 display while stocks considered to be least indicative of overall sector
 behavior should be assigned box locations in the lower right regions. This
 methodology is in keeping with the "visual momentum" concept of cognitive
 psychologists.
 In one preferred embodiment of the invention, the actual fractional
 deviations of the most recent trading prices of the stocks in the sector
 of interest from their corresponding reference values, in a selected set
 of reference values, are calculated using the expression:
 ##EQU1##
 Where the subscript "i" identifies the particular stock. In principle, the
 value of the fractional deviation can range from -1.0 to +.infin.. In
 realistic cases it is expected that the actual range would probably not
 exceed -0.20 to +0.20, corresponding to situations in which the particular
 stock is trading at 80 percent of its reference value and 120 percent of
 its reference value, respectively. The range will be, in general,
 dependant on the "age" of the reference value set. That is, the further in
 the past the reference value set was defined, the broader, on average, the
 range of fractional deviations will be.
 Translation of the current fractional deviation values to pixel colors is
 done in a two stage process. In the first stage the entire expected range
 of fractional deviation values is divided into a set of subranges which
 may be, but need not be, of equal size. Considerations, based on the
 ability of the human eye to readily distinguish similar colors from each
 other, have shown that a set of, typically, eleven subranges, is desirable
 for best resolution. These subranges may then be identified by, for
 example, positive sequential integer numbers. Thus, for a relatively
 limited expected range of fractional deviation values spanning the
 interval minus 0.050 to plus 0.050, corresponding to most recent trading
 prices differing, in general, by no more than .+-. five percent from a
 selected recent reference set of trading prices, the subregions might be
 defined and identified as follows:
 TABLE 1
 Fractional Deviation Value Subregion Identifier
 +0.045 to +.varies. 11
 +0.035 to +0.045 10
 +0.025 to +0.035 9
 +0.015 to +0.025 8
 +0.005 to +0.015 7
 -0.005 to +0.005 6
 -0.015 to -0.005 5
 -0.025 to -0.015 4
 -0.035 to -0.025 3
 -0.045 to -0.035 2
 -1.000 to -0.045 1
 Note that the subranges 1 and 11 effectively account for all outlying
 deviations. Occurrence of a significant number of fractional deviation
 values in the 1 and 11 subranges indicates that the expected range should
 be expanded and the subregion boundaries redefined. In this connection,
 automatic resealing of the expected range can be done employing techniques
 well known in the art, based on the number or fraction of the fractional
 deviation values falling in the end subregions.
 The set of integral values used to identify subregions will be recognized
 as having computational advantages. In this embodiment, the exact
 boundaries of each subregion must be specified. Thus, the bounds of the +9
 range, for example, described above, could be set either as:
 &gt;0.025 fractional deviation, and
 .ltoreq.0.035 fractional deviation
 or as
 .gtoreq.0.025 fractional deviation, and
 &lt;0.035 fractional deviation
 The choice between the two sets of rules is nominally arbitrary. However,
 which ever rule is adopted must encompass all possible values of
 fractional deviation and the rule must be consistently applied.
 In the second stage of converting recent trading prices to colors the set
 of subregions is mapped onto a set of related display pixel colors. In the
 preferred embodiment the set of colors range from pure orange through
 colors of progressively lower red content and higher yellow content
 through a medium, pure yellow color and on by way of decreasing yellow
 content and increasing blue content to a final pure green. The pure orange
 color corresponds to the subregion encompassing the most negative
 fractional deviation values; the medium pure yellow color corresponds to
 the subregion of little or no fractional deviation, and the pure green
 color corresponds to the subregion of the most positive fractional
 deviation values. Following the example given above:
 TABLE 2
 Subregion Identifier Color
 11 Green
 10 9 8 7
 ##STR1##
 6 Yellow
 5 4 3 2
 ##STR2##
 1 Orange
 As an alternative to the use of rigid, precise boundaries for the
 respective subregions it is also possible to utilize "dead bands" as are
 well known in control theory art in order to suppress possible flutter in
 the subregion identifier values at successive time steps.
 The net result is a color display on an electronic display device in which
 the current behavior of stock prices with respect to a select set of
 reference stock prices in a selected sector of the economy is summarized
 in a checkerboard-like collection of visual boxes whose individual colors
 show the current trends in trading prices of the corresponding stocks.
 Broad shifts or trends in stock prices in the sector appear as broad areas
 of a single color or of adjacent colors. Broad area shifts toward green,
 particularly in the upper left quadrant of the display, are indicative of
 potentially favorable conditions for investment in that sector. Area
 shifts toward orange particularly in the upper left quadrant, are
 indicative of declining prices. On the other hand, the appearance of a box
 of markedly different color than that of adjacent and nearby boxes will
 draw immediate attention to the particular stock associated with that box
 as departing from the general sector behavior. The quadrant in which the
 aberrant stock behavior is displayed can shed useful information regarding
 the significance of the abnormality. A further enhancement can be provided
 in the special case in which trading in one or more stocks on a given
 stock exchange is halted by that exchange in response to the development
 of abnormal conditions relating to that stock or those stocks. In this
 special case, the box/block corresponding to each affected stock would be
 assigned a unique color lying outside the set of colors normally used to
 indicate degrees of fractional deviation of current trading prices from
 reference values. In such a special case, of a stock for which trading has
 been halted, the preferred color in the box/block corresponding to that
 stock would be a pure red. While the foregoing selection of colors is
 preferred it should be appreciated that the invention will work with a
 number of different combinations of colors.
 In a second preferred embodiment of the invention, the first stage of the
 process for translating current fractional deviational values to pixel
 colors is modified to apply a smoothing algorithm to the raw fractional
 deviation values in the sector under consideration. In this approach, the
 current set of fractional deviation values is processed through a surface
 spline fit in which allowance is made for so-called "elastic spring"
 values. For purposes of generating the surface spline fit the fractional
 deviation values of the respective stocks represented in the display are
 associated with the spacial points located at the geometric centers of the
 corresponding boxes, referred to as locations "i" below. The magnitude of
 the "elastic-spring" value which is assigned to each stock, and therefore
 to its current fractional deviation value, is indicative (inversely) of
 the importance of that stock's behavior in evaluating sector behavior. A
 description of the application of surface spline methodology to the
 generation of surface functions in situations in which specific values of
 the functions are known only at discrete points is to be found in
 "Interpolation Using Surface Splines" by Robert Harder and Robert
 Desmarais in the Journal of Aircraft, Engineering Notes, dated February,
 1972, pages 189-191. The relevant equation is equation 17 in which the
 "elastic-spring" values are represented by the coefficients C.sub.i. A
 coefficient value of zero,
EQU C.sub.i =0.0
 sets the requirement that the fitting surface value at the location "i"
 must match exactly the value of the input at location ".sub.i ". In the
 current application this means that the value of the fitting surface at
 the center location of the designated box must be exactly the value of the
 fractional deviation of the most recent trading price of the stock
 corresponding to the designated box. If the coefficient value of a
 different stock, i.e. the value at the central location for that stock, is
 assigned a value greater than zero,
EQU C.sub.i &gt;0.0
 the value of the fit at the central location of box "i" is allowed to
 differ, in the interest of obtaining a smoothened fit, from the actual
 measured fractional deviation value of the corresponding stock. Thus, by
 assigning small values of the coefficient "C" to boxes/stocks that tend to
 dominate the assessment of the behavior of the sector of interest and
 larger values of the coefficient to boxes/stocks that have lesser impact
 on assessment of sector behavior, there results a fit that has been
 "smoothened" and is more nearly indicative of overall sector behavior. The
 assigned values of the coefficient "C" are stored in the elastic spring
 constants library which is part of the surface spline fit calculator
 subsystem 56 of the display generating apparatus illustrated in FIG. 2,
 which will be described more fully hereafter. Values of the "smoothened"
 fractional deviations obtained by evaluating the surface spline fitting
 function at each box location are then processed through the second stage
 of the translation to colors and the color display is drawn. This second
 stage is processed by the subregion classifier 42 also shown in FIG. 2.
 The surface spline fitting function and its adaptation to various
 applications is well known and within the ordinary skill of the art.
 It is to be noted that a comprehensive display of the behavior of the
 overall stock market, as reported by a specific stock exchange, can
 readily be generated by combining all of the individual sector displays as
 generated using this second embodiment provided all of the individual
 displays are based on reference value sets established at a common point
 in time and all utilize the same subregion boundary set or color code. The
 combined display would have the individual sector displays reduced, as
 necessary, in size and arranged in a row and column format. Since the fine
 detail of the individual displays has already been removed by surface
 spline fitting with elastic spring constants, shrinking in size of the
 individual displays should entail no further loss of detail.
 The methods and apparatus described above can be applied to other areas of
 financial transactions such as the bond market and the currency exchange
 market, both domestic and foreign. It can further be applied to
 commodities markets and other analogous processes that have related
 components with corresponding variable elements.
 FIG. 2 is a block diagram illustrating component portions of an apparatus
 that can be employed to generate a display in accordance with this
 invention. It is expected that the input link 80 will operate on a cycle
 time short enough that all transaction results that are carried by the
 on-line data source 32 will be captured by the input link 80 and passed to
 the updater buffer 34. Updating of the output display based on the current
 contents of the updater buffer 34 should occur approximately every thirty
 seconds, allowing time for the user to assimilate the information in the
 display before the display is updated again. The thirty seconds update
 criteria can be adjustable to accommodate the comfort of the user. It is
 desirable that the system be capable of shifting to a different reference
 value set and/or a different subregions boundary set within one, nominally
 thirty seconds update cycle through the corresponding user interfaces 31
 and 30 illustrated in FIG. 2. Updating of some of the libraries and the
 surface spline fit invariants can be done off-line and should be required
 infrequently and can be provided as updates to the software package.
 Referring to FIG. 2, the user can make a number of selections to define the
 display output through the user interfaces 30 and 31. User interface 30
 selects the subregion boundary and implements the chosen pattern code,
 e.g., color code, to be employed to represent the fractional deviation for
 each field on the display as previously described. User interface 31 sets
 the reference value set to be employed. The reference value set selector
 44 accepts the user's instructions from the interface 31, identifies the
 corresponding set of reference values in the library 46 and passes the
 selected set 14 for storage in the buffer 48 which provides a
 corresponding input to the fractional deviation calculator 50. Similarly,
 the subregion boundary set selector 36 retrieves the selected subregion
 boundary data from the library 38 in response to a user input 30 and
 stores the information in the buffer 40, which supplies a corresponding
 input 18 to the subregion classifier 42. The user also has the option to
 update the reference values to the then current stock prices in the
 updater buffer 34 by adding those prices to the reference value set
 library 46, through the user interface 78 and reference value update
 selector 76. These user inputs specify the operating parameters of the
 display system.
 In operation, results of transactions 10, as they occur, are fed into the
 data updater buffer 34 which also receives inputs from the stock/box
 coordinates library 58. The coordinates library 58 establishes the
 relative location of fields within the display. The data updater buffer 34
 communicates the most recent trading prices with their respective
 corresponding coordinates 12 to the fractional deviation calculator 50
 which supplies the current fractional deviation values to the surface
 spline fitting calculator 64. The surface spline fitting calculator module
 56, which is made up of the activation module 70, surface spline fitting
 calculator 64, buffer 68, surface spline fit preprocessor 66 and elastic
 spring constants library 82, also receives inputs from the stock/box
 coordinates library 58. The stock coordinates library 58 provides an input
 to both the surface spline fit preprocessor and the elastic spring
 constants library 82 to match the appropriate elastic spring constants to
 the corresponding coordinates via the surface spline fit preprocessor 66.
 The output of the surface spline fit preprocessor 66, indicated by
 reference character 26, is stored in a buffer 68 which supplies the
 appropriate value to the surface spline fit calculator 64. When the
 surface spline fit calculator module 56 is activated by the activation
 switch 70, through an input from the user interface 74, the fractional
 deviation calculator 50 supplies the current fractional deviation values
 16 to the surface spline fit calculator 64 to perform the "smoothened"
 calculation along with inputs 28 from the stock/box coordinates library
 and 26 from the buffer 68. The "smoothened" fractional deviation values 24
 are then inputted to the subregion classifier 42 through the subregion
 classifier selector switch 72. The fractional deviation calculator 50 also
 supplies the raw current fractional deviation values 16 to the subregion
 classifier 42 through the subregion classifier selector switch 72. The
 subregion classifier selector switch 72 selects one of the inputs 16 or
 24, as directed by the user input 74, for display. The subregion
 classifier 42 generates the subregion identifier values 20 which are
 collected in the output buffer 51 prior to being inputted to the output
 display generator 52 which in turn provides the display commands 22 to the
 output display screen 54. In this way, the output display is generated as
 previously described. When the raw current fractional deviation values 16
 are selected for display by the user input 74, through the subregion
 classifier selector switch 72, the surface spline function is inhibited by
 an input from the user interface 74 through the activation switch 70 and
 the surface spline fit calculator 64, which is quite computational
 resource intensive, is turned off.
 The surface spline fit preprocessor 66 is used only to calculate a set of
 nominally invariant factors that are used by the surface spline fit
 calculator 64. The only times that the preprocessor 66 actually runs are
 when:
 a. the location assigned to any stock in the display is changed to account,
 for example, for a perceived change in volatility, or a stock is added to
 or removed from the display; or
 b. the value of the elastic spring constant as assigned to a displayed
 stock is changed.
 Otherwise the preprocessor 66 supplies a set of constants to the calculator
 which is stored in the buffer 68 to be drawn upon by the surface spline
 fit calculator 64 when in operation. Thus, when the preprocessor 66
 operates, which normally would be quite infrequently, it stores its output
 in the buffer 68. Thereafter, when the calculator 64 runs, which is
 typically every 30 seconds, unless inhibited by a user command 74 to base
 the display on raw fractional deviation values, it would access the buffer
 68 and use the stored constants. Alternatively, the preprocessor could be
 completely off-line, running on a different platform with communications
 between it and the calculator 64, e.g., by disk or equivalent.
 It is desirable in some instances to couple the output display to a color
 printer. This would permit the user to obtain a hard copy print of the
 display on the screen, i.e., the sector trends at selected points in time.
 Alternatively, the most recent trading prices displayed and reference
 values can be stored on a hard drive or portable disk so the display can
 be regenerated for later review and comparison. Preferably the current
 reference value set identifier (date and time corresponding to the set)
 and the current subregion boundary-color mapping should appear on all
 output displays in a readily noticeable area to minimize user
 misinterpretation of the displays.
 Provision can also be made to substitute a set of simple geometric patterns
 for the colors in the respective boxes (or provide a combination of color
 and pattern) to allow color blind users to correctly interpret the
 information displayed on the output screen. An alternative set of patterns
 that can be used for this purpose is illustrated in FIG. 3. It should also
 be appreciated that the display generator described in U.S. Pat. No.
 4,774,049, with regard to a power distribution deviation calculator for a
 nuclear reactor, can be adapted to implement many of the blocks
 illustrated in FIG. 2.
 In another embodiment the basic methodology of the current invention
 relating to a financial data display system, can be applied with minor
 modifications to a display system for currency exchange transactions. Such
 an application can be enhanced by the following modifications to that
 previously described:
 a. a modest generalization of the mathematical expression used to define
 fractional deviation, and
 b. a notational change in the actual graphical display as will be described
 hereafter.
 The mathematical expression used to define the fractional deviation for
 this application is:
 ##EQU2##
 where the ".sub.i " and ".sub.j " each refer to each currency of interest
 with the exception that, by definition, ".sub.i " does not equal ".sub.j
 ".
 By way of illustration, one can consider a currency exchange involving
 converting units of currency "X" into units of currency "Y". In this case
 "X" is the currency sold, designated by the ".sub.i ", and "Y" is the
 currency bought, designated by ".sub.j " If the value of "Y" has risen
 against the value of "X" since the point in time at which the reference
 ratio was set, the current fraction deviation of the "X" to "Y" exchange
 will have a positive value. If one now considers the reverse transaction,
 converting "Y" to "X", one finds that "Y" is the currency sold, designated
 by ".sub.i ", and "X" is the currency bought, designated by ".sub.j ". If
 again, the value of "Y" has risen against the value of "X" since the
 reference was set, the current fractional deviation of the "Y" to the "X"
 transaction will have a negative value. Note that even though the two
 hypothetical transactions may have occurred simultaneously the absolute
 values of the respective fractional deviations would not be expected to be
 exactly equal due, in part, to the commission charge for each transaction,
 and, in part, due to the method used to normalize the two fractional
 deviation values. The effect of the cost of the transaction on the
 fractional deviation values decreases, typically, as the cost as a
 fraction of the whole value of the transaction decreases, i.e., the effect
 is less the larger the transaction. The effect of normalization decreases
 as the fractional changes in the relative currencies with respect to the
 reference decreases.
 The graphical display summarizing trends in currency exchange transactions
 takes the form illustrated in FIG. 4, which is similar to the display
 appropriate to stock and bond transactions illustrated in FIG. 1. The
 ".sub.i ", introduced above, becomes the row designator and the ".sub.j "
 becomes the column designator in the display array of this example,
 though, it should be appreciated that the reverse can apply equally as
 well.
 In the arrangement illustrated in FIG. 4 currency 1 could be, for example,
 dollars; currency 2 pounds sterling; currency 3 deutsche marks; currency 4
 yen; and so on. As previously described with respect to the stock related
 display, major world currencies which are presumed to be the most stable
 are assigned locations in the upper left hand region of the display. More
 volatile currencies would appear progressively further to the right and
 correspondingly further down in the array. The diagonal elements 84 of the
 array 62 are not meaningful in this application and could be colored black
 or grey, for example, to set them off from the rest of the display.
 In application, a user who is speculating in currencies and has, for
 example, deutsche marks to exchange would enter the display from the left
 at the row corresponding to deutsche marks being sold and would search
 across the row for boxes/blocks 60 whose colors trend from yellow toward
 green. The currencies corresponding to the columns in which the "greenish"
 blocks or boxes appear are those whose values have risen against the
 deutsche mark since the reference was set. The degree of "greenness" of
 such a box or block 60 is a measure of the current relative strength of
 the corresponding currency with respect to the deutsche mark. On the
 supposition that the indicated trend will continue, it would be
 appropriate to exchange deutsche marks for the most "green" currency of
 acceptable volatility.
 Continuing this line of reasoning, boxes or blocks 60 in the deutsche marks
 row with colors tending toward orange are seen to lie in columns
 corresponding to currencies whose values have fallen with respect to the
 deutsche mark since the reference was established. Again, on the
 supposition that the trend will continue, it would not be appropriate to
 exchange deutsche marks for such currencies. An observed shift in color in
 a box or block 60 from a weaker green to a stronger green is a clear
 indication that the apparent rising trend of the corresponding currency
 with respect to the deutsche mark is, in fact, continuing. The converse is
 also true.
 The display for showing currency exchange transaction trends can also be
 implemented by the circuit shown in FIG. 2 where the stock/box coordinates
 library 58 is programmed to identify the cells 84 in a manner that would
 be recognized by the subregion classifier 42 and output display generator
 52 so that the appropriate distinguishing coloring appears on the output
 display screen 54. Additionally, the fractional deviation calculator 50
 would have to be programmed to perform the fractional deviation
 calculation previously described for application to currency exchange
 transactions. The other changes to the respective libraries and other
 components should be similarly obvious to one skilled in the art.
 The further enhancement described below can be utilized in all described
 applications of the invention that do not make use of "smoothening" of a
 set of fractional deviation values by surface spline fitting or an
 equivalent method. "Smoothening" is only believed to be of substantial
 benefit when generating displays covering large portions of a total market
 and showing only large scale trends. The ability to obtain the fine detail
 and individual element performance that this enhancement would provide is
 of no practical consequence when "smoothening" is invoked.
 While the current invention yields a reliable indication of a linearized
 trend of the variable element with respect to an earlier reference value,
 it does not provide a convenient means for detecting a change in trends
 except by continually visually monitoring the color of a box/block
 corresponding to a stock, for example, of interest, and noting the change
 in color when it occurs. It would be desirable to be able to detect,
 continuous, automatic indications of the ongoing behavior of a variable
 element trend.
 A further enhanced embodiment of this invention achieves the foregoing
 objective by splitting each box/block 60 , for example, vertically as
 illustrated in FIG. 5, into two typically unequal areas, one showing the
 current color indication of the trend as described in the basic invention
 and the second showing the color of the most recent different indication
 of the trend for that particular market component. For example, in the
 split field 60 illustrated in FIG. 5A the left hand portion 86 would show
 the prior color coded trend information while the right hand portion 88
 would contain the current color coded trend information. If the fractional
 deviation value has not changed significantly since initialization of the
 display following the specification of reference conditions, the entire
 box/block will be a uniform color. If the color has changed in the
 interval since the specification of reference conditions the current
 indication appears in the preferably larger right hand part of the
 box/block 88 and the prior color indication appears in the preferably
 smaller left hand part of the box/block 86 as shown in FIG. 5. In order to
 avoid visual confusion it is necessary that a strong boundary
 differentiation be established for each box/block from the surrounding
 boxes/blocks 60. It should be appreciated that other geometric
 arrangements of the two components 86 and 88 of the field 60 are possible
 and in some instances desirable. For example, the geometric arrangements
 illustrated in FIGS. 5B and 5C can be employed to set off each box/block
 60 from the adjacent fields.
 FIG. 6 illustrates in block diagram form a circuit to implement the further
 improvement to display trends within a field 60. The corresponding
 elements which had been previously illustrated in FIGS. 2 are shown with
 like reference characters for comparison. The circuit utilizes two matrix
 buffers, referred to as the "old" matrix buffer 92 and the "new" matrix
 buffer 94. Initially the fractional deviation values for the first time
 step, after the reference value is established, are converted to subregion
 identifiers and the respective subregion identifier values 20 are stored
 as corresponding elements in both the "old" and the "new" matrix buffers
 92 and 94, respectively. This operation is performed in the matrix element
 comparitor 90 shown in FIG. 6. The contents of the two matrix buffers are
 passed to the display generator 52 which generates the graphical display
 using the integer values in the "old" matrix buffer 92 to set the pixel
 colors in the left hand portion 86 of the corresponding boxes/blocks 60
 and the integer values in the "new" matrix buffer 94 to set the pixel
 colors in the right portion 88 of the corresponding boxes/blocks.
 Thereafter, at each update time step the fractional deviation calculator
 50 recalculates each fractional deviation value, which is converted into
 an integer subregion identifier value in the subregion classifier 42. Then
 the current subregion identifier value is compared in the matrix element
 comparitor 90 to the corresponding value 98 that was determined in the
 most recent prior update cycle. At this point, the most recent prior value
 will still be stored as the corresponding element in the "new" matrix
 buffer 94. If the most recently determined subregion identifier is the
 same as the corresponding immediately prior value, the system proceeds to
 update the next fractional deviation value in the update cycle. If the
 most recently determined subregion identifier value is not the same as the
 corresponding immediately prior value, the immediately prior value 98 is
 stored in the appropriate location in the "old" matrix buffer 92
 corresponding to the field 86 shown in FIGS. 5A, B and C. The most
 recently calculated value 20 in that case is stored in the corresponding
 location in the "new" matrix buffer 94 corresponding to the subfield 88,
 and the system then proceeds to the updating of the next fractional
 deviation value in the update sequence. When the full set of fractional
 deviation values has been updated and the corresponding elements of the
 "old" and "new" matrix buffers 92 and 94 have been adjusted as required,
 the graphical display is generated as described above in connection with
 initialization.
 In an exemplary application of this improvement, consider the color pattern
 in a particular box/block 60 corresponding to an arbitrary selected stock.
 If the right hand portion 88 of the box is any "greenish" color and the
 left hand portion 86 is:
 a. yellow or a lighter green, the current stock price is above the
 reference value and rising; a buy situation;
 b. the same shade of green as the right portion, the stock price is above
 the reference value and holding nominally steady; probably a buy
 situation; or
 c. a darker shade of green, the stock price is above the reference value,
 but decreasing; a hold situation.
 If the right hand portion of the box/block 60 is yellow, the stock price is
 close to its reference value; a hold situation.
 If the right hand portion 88 of the box/block is any "orangish" color and
 the left hand portion 86 is:
 a. a darker shade of orange, the stock price is below its reference value,
 but rising; a hold situation;
 b. the same shade of orange as the right hand portion, the stock price is
 below its reference value and holding nominally steady; probably a sell
 situation; or
 c. yellow or a lighter shade of orange, the stock is below its reference
 value and falling; a sell situation.
 When the enhancement just described is incorporated in the invention it is
 highly desirable that the rigid boundaries of separation between the
 subregions defined by Table 1 be replaced by deadbands in order to
 suppress possible flutter in the subregion identifier values at successive
 time steps, as is well known in the art.
 Thus this invention provides a wealth of information about financial
 markets to an investor in a manner that can be easily absorbed and readily
 understood. Furthermore, the display highlights market trends and makes
 future predictions easier.
 While specific embodiments of the invention have been described in detail,
 it will be appreciated by those skilled in the art that various
 modifications and alternatives to those details could be developed in
 light of the overall teachings of the disclosure. Accordingly, the
 particular arrangements disclosed are meant to be illustrative only and
 not limiting as to the scope of the invention which is to be given the
 full breath of the appended claims and any and all equivalents thereof.