BasicModelD (Jackrabbit Oak 1.71-SNAPSHOT API)

java.lang.Object
- org.apache.lucene.search.similarities.BasicModel
- - org.apache.lucene.search.similarities.BasicModelD

```
public class BasicModelD
extends BasicModel
```
Implements the approximation of the binomial model with the divergence for DFR. The formula used in Lucene differs slightly from the one in the original paper: to avoid underflow for small values of N and F, N is increased by 1 and F is always increased by tfn+1.
WARNING: for terms that do not meet the expected random distribution (e.g. stopwords), this model may give poor performance, such as abnormally high scores for low tf values.

Constructor Summary

Constructors
Constructor Description

BasicModelD()
Sole constructor: parameter-free

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`float`	`score(BasicStats stats, float tfn)`	Returns the informative content score.
`String`	`toString()`	Subclasses must override this method to return the code of the basic model formula.

Methods inherited from class org.apache.lucene.search.similarities.BasicModel
explain

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - BasicModelD
```
public BasicModelD()
```
    Sole constructor: parameter-free
- Method Detail
  - score
```
public final float score(BasicStats stats,
                         float tfn)
```
    Description copied from class: BasicModel
    
    Returns the informative content score.
    
    Specified by:
    
    score in class BasicModel
  - toString
```
public String toString()
```
    Description copied from class: BasicModel
    
    Subclasses must override this method to return the code of the basic model formula. Refer to the original paper for the list.
    
    Specified by:
    
    toString in class BasicModel