Scan Criteria Overview

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Search Criteria - Overview

mrktscan_critradefinarea_sm.gifSearch criteria for a scan is defined in the Search Criteria area of the Search Criteria tabbed page.

The Search Criteria area has three sections:

A variety of criteria types, grouped according to the origin of their data and processes they employ, are available from the Selection Panel.

After selecting a criteria type, click the Add button to populate the expressions list with that type of expression, initially the new expression will contain default parameters.

Users can adjust many of the parameters' values. Select an expression in the list, the parameters controls for that expression will open in the Parameters Definition Area. Use the controls to change the values, the new values will be immediately reflected in the Parameters field in the Expressions List table.

For more information on each stage of this criteria expression definition process, click on the links above at left, or on an area in the graphic, above right.

Criteria Type Selection Panel

Criteria types are grouped into categories based on the type of data that they use and the methods in which that data is processed. The criteria types are closely related to similar components used in price charts, alerts and systems testing.

mrktscan_srchcriteriabar.gifOff-line scans in Your SOFTWARE can use criteria types from the following groups:

On-line scans are limited to the criteria types found in the Chart type group.

Click on one of the types above, or in the graphic at left, to go to that type's help topic. Each Help topic includes a description of the group as well as examples of some of the criteria parameters that the user can set.

The criteria types are located in the Available Criteria pane found in the left of the Search Criteria area. The criteria type categories can be collapsed or expanded by a single mouse click.

Select a single criteria type and click Add to place an instance of the criteria type in the Search Criteria Expressions List.

Multiple instances of the same criteria type can be added to the expression's list.

At the same time the expression is created in the list, the parameters dialog controls will open in the Search Criteria Parameters Definition Area in the bottom-right of the work area. Users can alter the default parameters from this area.

Use the buttons at the bottom of the Available Criteria list to manage the contents of the Search Criteria Expressions List.

Add new criteria expressions by selecting them in the Available Criteria list and clicking Add.

To remove an expression, select the expression in the Search Criteria Expressions List and then click the Remove button at the bottom of the Available Criteria list.

Off-Line vs. On-Line Criteria Types

Off-Line scans have the full range of criteria types available for inclusion as criteria expressions.

On-Line scans can only use the five Chart Criteria Types: Gap Up/Down, New High/Low and Price. When an On-Line scan is being defined, only the Chart group containing these options will appear in the Available Criteria selection panel.

Criteria Expression List

The Search Criteria Expressions List contains all of the individual criteria expressions that will form the logic of the scan.

Use the Add button at the bottom of the Available Criteria panel to populate the expressions list.

mrktscan_criterialist.gifMultiple instances of the same criteria type can be added to the list, the parameters can then be changed in the Search Criteria Parameters area immediately below the list.

Each row of the Search Criteria Expressions list has two components for each expression: Selected Criteria and Parameters.

The Selected Criteria refers to the criteria type, and the Parameters include the user defined variables. When these two components are read together, the resulting string will give an indication of how the particular criteria expression will operate in the scan.

The user defines the variables in the Criteria Parameters Definition Area, located immediately beneath the list.

Edit Existing Criteria Expressions

All of the expressions can be edited from this work page.

Select an expression in the list, its parameter values will display in the Search Criteria Parameters area immediately below the list.

Change the values using the various controls or by direct entry, and Save butn_save.gif.

Criteria Parameters Definition Area

The user defines each criteria type's variables in the Criteria Parameters Definition Area, located immediately beneath the Search Criteria Expressions List.

As users enter the values of the parameters in the Search Criteria Parameters area, those changes  are immediately reflected in the text in the Parameters field in the expressions list above it.

Each criteria has different parameters.

In general, there are two broad types of Search Criteria Parameters dialogs:

Click on the links above to go to an example of each type that will illustrate some of their common features and provide more information.

Simple criteria is used by many of the Chart group's criteria types.

The Chart group's Price criteria type, as well as the Hi-Lites,  Indicators, and Signals criteria types, employ complex expression formulae to define the parameters of their expressions.

The Chart group's Price criteria type and the Indicators criteria types, employ complex expression formulae to define the parameters of their expressions.

The Chart group's Price criteria type, as well as the Hi-Lites and Indicators criteria types, employ complex expression formulae to define the parameters of their expressions.

The scan expressions employ the principles used to create the similarly named Hi-Lites, Indicators and Signals and include a range of numbers, intervals, logical expressions, and many other parameter types in their formulae.

The scan expressions employ the principles used to create the similarly named Indicators and include a range of numbers, intervals, logical expressions, and many other parameter types in their formulae.

Simple Criteria Entry Dialog - Example

mrktscan_chrtcrit_simple.gifThe New High criteria item for the Chart scan type is a typical simple criteria entry box.

The search criteria is a Hew High in the symbol's price data, and the user defines the number of days prior to the day that the scan will be performed on.

The user enters the value of the number of days in the text box. The entry can  either be manually typed in, or the up/down selector button.

When a new value is selected, it will immediately be added to the Parameters expression in the list.

All of the Chart type criteria, except for Price, have simple criteria entry boxes in their Search Criteria Parameters areas.

Complex Expression Formula Dialog - Example

The parameters dialog for the Price criteria type, found in the Charts group of the Available Criteria Panel, is an example of a complex expression formula:

mrktscan_chrtcrit_complex.gif

Complex parameters often have three components which all need to be logically related to each other in order to create the search criteria expression. The scan criteria will string the three together as follows:

(First Value)+(Operator)+(Second Value)

This information is displayed in the Parameters field of the Search Criteria Expressions List (immediately above the Parameters definition area), which converts the selected search criteria into plain English.

As you adjust the criteria and its values, the Parameters field of the expression list will change. In this way you can confirm what the current settings will scan for before accepting it.

When creating a scan criteria it is important to have a clear understanding of your scanning objective. In this way, you will be able to adjust the many options to achieve the desired criteria.

It is also important to consider the other expressions which you create for the scan, and be careful not to create contradictory expressions.

First Value

mrktscan_chrtcrit_cplx1valu.gif

The First Value is the main item that the scan will be run against. Click on the drop down text box to view the available data type options.

Data Type

For the First Value, you can select any of the price data type options that are available from the server. The data types, and values that apply to them, will depend on the criteria type.

Value - Day(s) ago

Then, in the next text box, type in or scroll to the number of days you wish to use the data from. Leaving the setting at 0 will use the last data date available (usually meaning ‘today’). Remember that the base day is set when you specify the scope of the scan. By default it is the most recent day's data, but user's can select a specific date to run the scan on. In such a case, the Day(s) ago setting in this parameter would be from that day rather than the current day.

Modifier - Modify Result

mrktscan_chrtcrit_cplxmodfy.gifThe value that is returned from the above two settings can be further modified by a set amount.

Increase/Decrease uses whole numbers.

Percentages can be applied using the Multiply/Divide functions, for example modifying the result to show a 5% discount can be accomplished by setting this value to "Multiply by 0.95".

Operator

The Operator lets you specify how the first value interacts with, or is compared to, the second value:

indicatorscritoperatorvalu.gif

You can see there are a number of options within this drop down menu. Again, the exact array populating the drop-down menu depends on the criteria type.

You need to select the option that describes the relationship between the First Value and the Second Value.

Modifier - Time period

Some operators have an additional modifier that must be set.

In this example, the Crosses Above/Below operator has a Within the last "x" Days modifier.

Second Value

Use the Second Value to specify the criteria that the First Value is compared to.

In the price example, the options for the Second Value include all those available in the First Value's drop-down list. This allows you to compare the open to the close of the current day, or the high of today compared to the high of 5 days ago.

mrktscan_chrtcrit_cplx2valu.gif

There is also an additional option of Numeric Value.... This allows you to specify a value to compare the First Value with. For example, you could specify a High of today is Greater than a Numeric Value of 2. This means that any securities whose high of today is more than two dollars will be included in the scan results.

Note -  When referring to price based values, the numeric value is based on dollars. A value of 2 will equal $2.

The Range value allows the First Value to be specified in relation to a previous day's price range.

The price Range is calculated using the high and low prices. The range for the value is the converted into 100 percentile points and the number of the percentile points set by the user is compared with the First Value using the operator.

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