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Replace Missing Values (In Database)

Synopsis

Replaces missing values in the data.

Description

Replaces missing values in examples. If a value is missing, it is replaced by one of the functions "minimum", "maximum", "average", and "none", which is applied to the non missing attribute values of the example set. "none" means that the value is not replaced. The function can be selected using the parameter list columns. If an attribute's name appears in this list as a key, the value is used as the function name. If the attribute's name is not in the list, the function specified by the default parameter is used. The replenishment "value" indicates that the user defined parameter should be used for the replacement. It can be a nominal or a numerical value.

Input

example set input

Output

example set output

Parameters

Attribute filter type

The condition specifies which attributes are selected or affected by this operator.

Attribute

The attribute which should be chosen.

Attributes

The attribute which should be chosen.

Regular expression

A regular expression for the names of the attributes which should be kept.

Use except expression

If enabled, an exception to the specified regular expression might be specified. Attributes of matching this will be filtered out, although matching the first expression.

Except regular expression

A regular expression for the names of the attributes which should be filtered out although matching the above regular expression.

Value type

The value type of the attributes.

Use value type exception

If enabled, an exception to the specified value type might be specified. Attributes of this type will be filtered out, although matching the first specified type.

Except value type

Except this value type.

Block type

The block type of the attributes.

Use block type exception

If enabled, an exception to the specified block type might be specified.

Except block type

Except this block type.

Numeric condition

Parameter string for the condition, e.g. >= 5

Invert selection

Indicates if only attributes should be accepted which would normally filtered.

Default

Function to apply to all columns that are not explicitly specified by parameter 'columns'.

Columns

List of replacement functions for each column.

Replenishment value

This value is used for some of the replenishment types.