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<div class="subTitle">org.apache.mahout.cf.taste.impl.recommender</div>
<h2 title="Class GenericItemBasedRecommender" class="title">Class GenericItemBasedRecommender</h2>
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<ul class="inheritance">
<li><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</a></li>
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<ul class="inheritance">
<li><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html" title="class in org.apache.mahout.cf.taste.impl.recommender">org.apache.mahout.cf.taste.impl.recommender.AbstractRecommender</a></li>
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<ul class="inheritance">
<li>org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender</li>
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<dt>All Implemented Interfaces:</dt>
<dd><a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html" title="interface in org.apache.mahout.cf.taste.common">Refreshable</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html" title="interface in org.apache.mahout.cf.taste.recommender">Recommender</a></dd>
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<dl>
<dt>Direct Known Subclasses:</dt>
<dd><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericBooleanPrefItemBasedRecommender.html" title="class in org.apache.mahout.cf.taste.impl.recommender">GenericBooleanPrefItemBasedRecommender</a></dd>
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<hr>
<br>
<pre>public class <span class="typeNameLabel">GenericItemBasedRecommender</span>
extends <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html" title="class in org.apache.mahout.cf.taste.impl.recommender">AbstractRecommender</a>
implements <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></pre>
<div class="block"><p>
A simple <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html" title="interface in org.apache.mahout.cf.taste.recommender"><code>Recommender</code></a> which uses a given
<a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a> and
<a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity"><code>ItemSimilarity</code></a> to produce recommendations. This class
represents Taste's support for item-based recommenders.
</p>
<p>
The <a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity"><code>ItemSimilarity</code></a> is the most important point to discuss
here. Item-based recommenders are useful because they can take advantage of something to be very fast: they
base their computations on item similarity, not user similarity, and item similarity is relatively static.
It can be precomputed, instead of re-computed in real time.
</p>
<p>
Thus it's strongly recommended that you use
<a href="../../../../../../../org/apache/mahout/cf/taste/impl/similarity/GenericItemSimilarity.html" title="class in org.apache.mahout.cf.taste.impl.similarity"><code>GenericItemSimilarity</code></a> with pre-computed similarities if
you're going to use this class. You can use
<a href="../../../../../../../org/apache/mahout/cf/taste/impl/similarity/PearsonCorrelationSimilarity.html" title="class in org.apache.mahout.cf.taste.impl.similarity"><code>PearsonCorrelationSimilarity</code></a> too, which computes
similarities in real-time, but will probably find this painfully slow for large amounts of data.
</p></div>
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<td class="colFirst"><code>static class&nbsp;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.MostSimilarEstimator.html" title="class in org.apache.mahout.cf.taste.impl.recommender">GenericItemBasedRecommender.MostSimilarEstimator</a></span></code>&nbsp;</td>
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<th class="colOne" scope="col">Constructor and Description</th>
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<td class="colOne"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#GenericItemBasedRecommender-org.apache.mahout.cf.taste.model.DataModel-org.apache.mahout.cf.taste.similarity.ItemSimilarity-">GenericItemBasedRecommender</a></span>(<a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model">DataModel</a>&nbsp;dataModel,
<a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity">ItemSimilarity</a>&nbsp;similarity)</code>&nbsp;</td>
</tr>
<tr class="rowColor">
<td class="colOne"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#GenericItemBasedRecommender-org.apache.mahout.cf.taste.model.DataModel-org.apache.mahout.cf.taste.similarity.ItemSimilarity-org.apache.mahout.cf.taste.recommender.CandidateItemsStrategy-org.apache.mahout.cf.taste.recommender.MostSimilarItemsCandidateItemsStrategy-">GenericItemBasedRecommender</a></span>(<a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model">DataModel</a>&nbsp;dataModel,
<a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity">ItemSimilarity</a>&nbsp;similarity,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/CandidateItemsStrategy.html" title="interface in org.apache.mahout.cf.taste.recommender">CandidateItemsStrategy</a>&nbsp;candidateItemsStrategy,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/MostSimilarItemsCandidateItemsStrategy.html" title="interface in org.apache.mahout.cf.taste.recommender">MostSimilarItemsCandidateItemsStrategy</a>&nbsp;mostSimilarItemsCandidateItemsStrategy)</code>&nbsp;</td>
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<caption><span id="t0" class="activeTableTab"><span>All Methods</span><span class="tabEnd">&nbsp;</span></span><span id="t1" class="tableTab"><span><a href="javascript:show(1);">Static Methods</a></span><span class="tabEnd">&nbsp;</span></span><span id="t2" class="tableTab"><span><a href="javascript:show(2);">Instance Methods</a></span><span class="tabEnd">&nbsp;</span></span><span id="t4" class="tableTab"><span><a href="javascript:show(8);">Concrete Methods</a></span><span class="tabEnd">&nbsp;</span></span></caption>
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<th class="colFirst" scope="col">Modifier and Type</th>
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<td class="colFirst"><code>protected float</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#doEstimatePreference-long-org.apache.mahout.cf.taste.model.PreferenceArray-long-">doEstimatePreference</a></span>(long&nbsp;userID,
<a href="../../../../../../../org/apache/mahout/cf/taste/model/PreferenceArray.html" title="interface in org.apache.mahout.cf.taste.model">PreferenceArray</a>&nbsp;preferencesFromUser,
long&nbsp;itemID)</code>&nbsp;</td>
</tr>
<tr id="i1" class="rowColor">
<td class="colFirst"><code>float</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#estimatePreference-long-long-">estimatePreference</a></span>(long&nbsp;userID,
long&nbsp;itemID)</code>&nbsp;</td>
</tr>
<tr id="i2" class="altColor">
<td class="colFirst"><code>protected static <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/MostSimilarItemsCandidateItemsStrategy.html" title="interface in org.apache.mahout.cf.taste.recommender">MostSimilarItemsCandidateItemsStrategy</a></code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#getDefaultMostSimilarItemsCandidateItemsStrategy--">getDefaultMostSimilarItemsCandidateItemsStrategy</a></span>()</code>&nbsp;</td>
</tr>
<tr id="i3" class="rowColor">
<td class="colFirst"><code><a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity">ItemSimilarity</a></code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#getSimilarity--">getSimilarity</a></span>()</code>&nbsp;</td>
</tr>
<tr id="i4" class="altColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#mostSimilarItems-long:A-int-">mostSimilarItems</a></span>(long[]&nbsp;itemIDs,
int&nbsp;howMany)</code>&nbsp;</td>
</tr>
<tr id="i5" class="rowColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#mostSimilarItems-long:A-int-boolean-">mostSimilarItems</a></span>(long[]&nbsp;itemIDs,
int&nbsp;howMany,
boolean&nbsp;excludeItemIfNotSimilarToAll)</code>&nbsp;</td>
</tr>
<tr id="i6" class="altColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#mostSimilarItems-long:A-int-org.apache.mahout.cf.taste.recommender.Rescorer-">mostSimilarItems</a></span>(long[]&nbsp;itemIDs,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">Rescorer</a>&lt;<a href="../../../../../../../org/apache/mahout/common/LongPair.html" title="class in org.apache.mahout.common">LongPair</a>&gt;&nbsp;rescorer)</code>&nbsp;</td>
</tr>
<tr id="i7" class="rowColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#mostSimilarItems-long:A-int-org.apache.mahout.cf.taste.recommender.Rescorer-boolean-">mostSimilarItems</a></span>(long[]&nbsp;itemIDs,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">Rescorer</a>&lt;<a href="../../../../../../../org/apache/mahout/common/LongPair.html" title="class in org.apache.mahout.common">LongPair</a>&gt;&nbsp;rescorer,
boolean&nbsp;excludeItemIfNotSimilarToAll)</code>&nbsp;</td>
</tr>
<tr id="i8" class="altColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#mostSimilarItems-long-int-">mostSimilarItems</a></span>(long&nbsp;itemID,
int&nbsp;howMany)</code>&nbsp;</td>
</tr>
<tr id="i9" class="rowColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#mostSimilarItems-long-int-org.apache.mahout.cf.taste.recommender.Rescorer-">mostSimilarItems</a></span>(long&nbsp;itemID,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">Rescorer</a>&lt;<a href="../../../../../../../org/apache/mahout/common/LongPair.html" title="class in org.apache.mahout.common">LongPair</a>&gt;&nbsp;rescorer)</code>&nbsp;</td>
</tr>
<tr id="i10" class="altColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#recommend-long-int-org.apache.mahout.cf.taste.recommender.IDRescorer-boolean-">recommend</a></span>(long&nbsp;userID,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/IDRescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">IDRescorer</a>&nbsp;rescorer,
boolean&nbsp;includeKnownItems)</code>&nbsp;</td>
</tr>
<tr id="i11" class="rowColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#recommendedBecause-long-long-int-">recommendedBecause</a></span>(long&nbsp;userID,
long&nbsp;itemID,
int&nbsp;howMany)</code>
<div class="block">
Lists the items that were most influential in recommending a given item to a given user.</div>
</td>
</tr>
<tr id="i12" class="altColor">
<td class="colFirst"><code>void</code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#refresh-java.util.Collection-">refresh</a></span>(<a href="http://docs.oracle.com/javase/7/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html" title="interface in org.apache.mahout.cf.taste.common">Refreshable</a>&gt;&nbsp;alreadyRefreshed)</code>
<div class="block">
Triggers "refresh" -- whatever that means -- of the implementation.</div>
</td>
</tr>
<tr id="i13" class="rowColor">
<td class="colFirst"><code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a></code></td>
<td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/GenericItemBasedRecommender.html#toString--">toString</a></span>()</code>&nbsp;</td>
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<h3>Methods inherited from class&nbsp;org.apache.mahout.cf.taste.impl.recommender.<a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html" title="class in org.apache.mahout.cf.taste.impl.recommender">AbstractRecommender</a></h3>
<code><a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#getAllOtherItems-long-org.apache.mahout.cf.taste.model.PreferenceArray-boolean-">getAllOtherItems</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#getDataModel--">getDataModel</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#getDefaultCandidateItemsStrategy--">getDefaultCandidateItemsStrategy</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#recommend-long-int-">recommend</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#recommend-long-int-boolean-">recommend</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#recommend-long-int-org.apache.mahout.cf.taste.recommender.IDRescorer-">recommend</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#removePreference-long-long-">removePreference</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/impl/recommender/AbstractRecommender.html#setPreference-long-long-float-">setPreference</a></code></li>
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<code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#clone--" title="class or interface in java.lang">clone</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#equals-java.lang.Object-" title="class or interface in java.lang">equals</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#finalize--" title="class or interface in java.lang">finalize</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#getClass--" title="class or interface in java.lang">getClass</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#hashCode--" title="class or interface in java.lang">hashCode</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#notify--" title="class or interface in java.lang">notify</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#notifyAll--" title="class or interface in java.lang">notifyAll</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait--" title="class or interface in java.lang">wait</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait-long-" title="class or interface in java.lang">wait</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait-long-int-" title="class or interface in java.lang">wait</a></code></li>
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<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#getDataModel--">getDataModel</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#recommend-long-int-">recommend</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#recommend-long-int-boolean-">recommend</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#recommend-long-int-org.apache.mahout.cf.taste.recommender.IDRescorer-">recommend</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#removePreference-long-long-">removePreference</a>, <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#setPreference-long-long-float-">setPreference</a></code></li>
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<pre>public&nbsp;GenericItemBasedRecommender(<a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model">DataModel</a>&nbsp;dataModel,
<a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity">ItemSimilarity</a>&nbsp;similarity,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/CandidateItemsStrategy.html" title="interface in org.apache.mahout.cf.taste.recommender">CandidateItemsStrategy</a>&nbsp;candidateItemsStrategy,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/MostSimilarItemsCandidateItemsStrategy.html" title="interface in org.apache.mahout.cf.taste.recommender">MostSimilarItemsCandidateItemsStrategy</a>&nbsp;mostSimilarItemsCandidateItemsStrategy)</pre>
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<pre>public&nbsp;GenericItemBasedRecommender(<a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model">DataModel</a>&nbsp;dataModel,
<a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity">ItemSimilarity</a>&nbsp;similarity)</pre>
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<pre>protected static&nbsp;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/MostSimilarItemsCandidateItemsStrategy.html" title="interface in org.apache.mahout.cf.taste.recommender">MostSimilarItemsCandidateItemsStrategy</a>&nbsp;getDefaultMostSimilarItemsCandidateItemsStrategy()</pre>
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<h4>getSimilarity</h4>
<pre>public&nbsp;<a href="../../../../../../../org/apache/mahout/cf/taste/similarity/ItemSimilarity.html" title="interface in org.apache.mahout.cf.taste.similarity">ItemSimilarity</a>&nbsp;getSimilarity()</pre>
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<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;recommend(long&nbsp;userID,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/IDRescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">IDRescorer</a>&nbsp;rescorer,
boolean&nbsp;includeKnownItems)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#recommend-long-int-org.apache.mahout.cf.taste.recommender.IDRescorer-boolean-">recommend</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html" title="interface in org.apache.mahout.cf.taste.recommender">Recommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>userID</code> - user for which recommendations are to be computed</dd>
<dd><code>howMany</code> - desired number of recommendations</dd>
<dd><code>rescorer</code> - rescoring function to apply before final list of recommendations is determined</dd>
<dd><code>includeKnownItems</code> - whether to include items already known by the user in recommendations</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util"><code>List</code></a> of recommended <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender"><code>RecommendedItem</code></a>s, ordered from most strongly recommend to
least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
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<pre>public&nbsp;float&nbsp;estimatePreference(long&nbsp;userID,
long&nbsp;itemID)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
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<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html#estimatePreference-long-long-">estimatePreference</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Recommender.html" title="interface in org.apache.mahout.cf.taste.recommender">Recommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>userID</code> - user ID whose preference is to be estimated</dd>
<dd><code>itemID</code> - item ID to estimate preference for</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>an estimated preference if the user has not expressed a preference for the item, or else the
user's actual preference for the item. If a preference cannot be estimated, returns
<a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Double.html?is-external=true#NaN" title="class or interface in java.lang"><code>Double.NaN</code></a></dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
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<h4>mostSimilarItems</h4>
<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;mostSimilarItems(long&nbsp;itemID,
int&nbsp;howMany)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#mostSimilarItems-long-int-">mostSimilarItems</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>itemID</code> - ID of item for which to find most similar other items</dd>
<dd><code>howMany</code> - desired number of most similar items to find</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>items most similar to the given item, ordered from most similar to least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
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<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;mostSimilarItems(long&nbsp;itemID,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">Rescorer</a>&lt;<a href="../../../../../../../org/apache/mahout/common/LongPair.html" title="class in org.apache.mahout.common">LongPair</a>&gt;&nbsp;rescorer)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#mostSimilarItems-long-int-org.apache.mahout.cf.taste.recommender.Rescorer-">mostSimilarItems</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>itemID</code> - ID of item for which to find most similar other items</dd>
<dd><code>howMany</code> - desired number of most similar items to find</dd>
<dd><code>rescorer</code> - <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender"><code>Rescorer</code></a> which can adjust item-item similarity estimates used to determine most similar
items</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>itemss most similar to the given item, ordered from most similar to least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
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<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;mostSimilarItems(long[]&nbsp;itemIDs,
int&nbsp;howMany)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#mostSimilarItems-long:A-int-">mostSimilarItems</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>itemIDs</code> - IDs of item for which to find most similar other items</dd>
<dd><code>howMany</code> - desired number of most similar items to find estimates used to determine most similar items</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>items most similar to the given items, ordered from most similar to least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
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<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;mostSimilarItems(long[]&nbsp;itemIDs,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">Rescorer</a>&lt;<a href="../../../../../../../org/apache/mahout/common/LongPair.html" title="class in org.apache.mahout.common">LongPair</a>&gt;&nbsp;rescorer)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#mostSimilarItems-long:A-int-org.apache.mahout.cf.taste.recommender.Rescorer-">mostSimilarItems</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>itemIDs</code> - IDs of item for which to find most similar other items</dd>
<dd><code>howMany</code> - desired number of most similar items to find</dd>
<dd><code>rescorer</code> - <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender"><code>Rescorer</code></a> which can adjust item-item similarity estimates used to determine most similar
items</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>items most similar to the given items, ordered from most similar to least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
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<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;mostSimilarItems(long[]&nbsp;itemIDs,
int&nbsp;howMany,
boolean&nbsp;excludeItemIfNotSimilarToAll)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#mostSimilarItems-long:A-int-boolean-">mostSimilarItems</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>itemIDs</code> - IDs of item for which to find most similar other items</dd>
<dd><code>howMany</code> - desired number of most similar items to find</dd>
<dd><code>excludeItemIfNotSimilarToAll</code> - exclude an item if it is not similar to each of the input items</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>items most similar to the given items, ordered from most similar to least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
</dl>
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<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;mostSimilarItems(long[]&nbsp;itemIDs,
int&nbsp;howMany,
<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender">Rescorer</a>&lt;<a href="../../../../../../../org/apache/mahout/common/LongPair.html" title="class in org.apache.mahout.common">LongPair</a>&gt;&nbsp;rescorer,
boolean&nbsp;excludeItemIfNotSimilarToAll)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#mostSimilarItems-long:A-int-org.apache.mahout.cf.taste.recommender.Rescorer-boolean-">mostSimilarItems</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>itemIDs</code> - IDs of item for which to find most similar other items</dd>
<dd><code>howMany</code> - desired number of most similar items to find</dd>
<dd><code>rescorer</code> - <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/Rescorer.html" title="interface in org.apache.mahout.cf.taste.recommender"><code>Rescorer</code></a> which can adjust item-item similarity estimates used to determine most similar
items</dd>
<dd><code>excludeItemIfNotSimilarToAll</code> - exclude an item if it is not similar to each of the input items</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>items most similar to the given items, ordered from most similar to least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
</dl>
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</ul>
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<h4>recommendedBecause</h4>
<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender">RecommendedItem</a>&gt;&nbsp;recommendedBecause(long&nbsp;userID,
long&nbsp;itemID,
int&nbsp;howMany)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<div class="block"><span class="descfrmTypeLabel">Description copied from interface:&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#recommendedBecause-long-long-int-">ItemBasedRecommender</a></code></span></div>
<div class="block"><p>
Lists the items that were most influential in recommending a given item to a given user. Exactly how this
is determined is left to the implementation, but, generally this will return items that the user prefers
and that are similar to the given item.
</p>
<p>
This returns a <a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util"><code>List</code></a> of <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender"><code>RecommendedItem</code></a> which is a little misleading since it's returning
recommend<strong>ing</strong> items, but, I thought it more natural to just reuse this class since it
encapsulates an item and value. The value here does not necessarily have a consistent interpretation or
expected range; it will be higher the more influential the item was in the recommendation.
</p></div>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html#recommendedBecause-long-long-int-">recommendedBecause</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/recommender/ItemBasedRecommender.html" title="interface in org.apache.mahout.cf.taste.recommender">ItemBasedRecommender</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>userID</code> - ID of user who was recommended the item</dd>
<dd><code>itemID</code> - ID of item that was recommended</dd>
<dd><code>howMany</code> - maximum number of items to return</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd><a href="http://docs.oracle.com/javase/7/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util"><code>List</code></a> of <a href="../../../../../../../org/apache/mahout/cf/taste/recommender/RecommendedItem.html" title="interface in org.apache.mahout.cf.taste.recommender"><code>RecommendedItem</code></a>, ordered from most influential in recommended the given
item to least</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code> - if an error occurs while accessing the <a href="../../../../../../../org/apache/mahout/cf/taste/model/DataModel.html" title="interface in org.apache.mahout.cf.taste.model"><code>DataModel</code></a></dd>
</dl>
</li>
</ul>
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<h4>doEstimatePreference</h4>
<pre>protected&nbsp;float&nbsp;doEstimatePreference(long&nbsp;userID,
<a href="../../../../../../../org/apache/mahout/cf/taste/model/PreferenceArray.html" title="interface in org.apache.mahout.cf.taste.model">PreferenceArray</a>&nbsp;preferencesFromUser,
long&nbsp;itemID)
throws <a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></pre>
<dl>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/TasteException.html" title="class in org.apache.mahout.cf.taste.common">TasteException</a></code></dd>
</dl>
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<a name="refresh-java.util.Collection-">
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<h4>refresh</h4>
<pre>public&nbsp;void&nbsp;refresh(<a href="http://docs.oracle.com/javase/7/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html" title="interface in org.apache.mahout.cf.taste.common">Refreshable</a>&gt;&nbsp;alreadyRefreshed)</pre>
<div class="block"><span class="descfrmTypeLabel">Description copied from interface:&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html#refresh-java.util.Collection-">Refreshable</a></code></span></div>
<div class="block"><p>
Triggers "refresh" -- whatever that means -- of the implementation. The general contract is that any
<a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html" title="interface in org.apache.mahout.cf.taste.common"><code>Refreshable</code></a> should always leave itself in a consistent, operational state, and that the refresh
atomically updates internal state from old to new.
</p></div>
<dl>
<dt><span class="overrideSpecifyLabel">Specified by:</span></dt>
<dd><code><a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html#refresh-java.util.Collection-">refresh</a></code>&nbsp;in interface&nbsp;<code><a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html" title="interface in org.apache.mahout.cf.taste.common">Refreshable</a></code></dd>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>alreadyRefreshed</code> - <a href="../../../../../../../org/apache/mahout/cf/taste/common/Refreshable.html" title="interface in org.apache.mahout.cf.taste.common"><code>Refreshable</code></a>s that are known to have already been
refreshed as a result of an initial call to a {#refresh(Collection)} method on some
object. This ensure that objects in a refresh dependency graph aren't refreshed twice
needlessly.</dd>
</dl>
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<h4>toString</h4>
<pre>public&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;toString()</pre>
<dl>
<dt><span class="overrideSpecifyLabel">Overrides:</span></dt>
<dd><code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#toString--" title="class or interface in java.lang">toString</a></code>&nbsp;in class&nbsp;<code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</a></code></dd>
</dl>
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