calculated independently.
Unlike Naive Bayes, Logistic Regression must satisfy the conditional independence hypothesis (because it does not evaluate the posterior probability ). However, the contribution of each feature is calculated independently, that is, LR will not automatically help you combine different features to generate new feature (this fantasy cannot be held at all times, that is, decision tree, lsa, plsa, LDA or what you want to do ). For example, if you need a feature such as TF *
.
In a situation like searching for terrorists, where we have CT that there are few terrorists operating at any one time.If we use data mining technology to mine a large number of terrorist events every day, such technology is ineffective, even if there are indeed several terrorist events...
3 things useful to know
If you are studying data mining, the following basic concepts are very important,
1. The Tf. IDF measure of word importance.2. Hash Funct
) # Use the tf-idf model to obtain the document's tf-idf model corpus_tfidf = tfidf [corpus] # Calculate the tf-idf value # for doc in corpus_tfidf: # print doc ### '''q _ file = open ('C: \ Users \ kk \ Desktop \ q.txt','your query1_q_file.readline(1_q_file.close({vec_bow1_dictionary.doc 2bow (query. split ('') # convert the request to the word band model vec_tf
']X_new_counts =count_vect.transform (docs_new) x_new_tfidf=tfidf_transformer.fit_transform (X_new_ Counts) predicted=clf.predict (X_NEW_TFIDF) fordoc,categoryinzip (Docs_new, predicted):print '%r=>%s ' % (doc,twenty_train.target_ Names[category]Categorize 2,257 of documents in Fetch_20newsgroups
Count the occurrences of each word
With TF-IDF statistics, TF is the number of occurrences of each word in a document divided by the total numb
feature, but the contribution of each feature is calculated independently.The logistic regression does not need to satisfy the conditional independent hypothesis like naive Bayes (because it does not have a posteriori probability). But the contribution of each feature is calculated independently, that is, LR does not automatically help you combine different features to generate new feature (it is a matter of time not to have this illusion, that is, the decision tree, LSA, pLSA, LDA, or yourself
Transferred from: http://www.oschina.net/question/5189_7707 The Lucene scoring system/mechanism (Lucene scoring) is a core part of Lucene's reputation. It hides a lot of complicated details for the user, which makes it easy for users to use Lucene. But personally think: if you want to adjust the score (or structure sort) according to your own application, it is very important to have a thorough understanding of lucene scoring mechanism. The Lucene scoring combination uses the vector space model
-defined dictionaries"---HTTPS://GITHUB.COM/FXSJY/JIEBA/ISSUES/14
Keyword extraction
Keyword extraction based on TF-IDF algorithmimport jieba.analyse
Jieba.analyse.extract_tags (sentence, topk=20, Withweight=false, allowpos= ())
Sentence for the text to be extracted
TopK is the keyword that returns several TF/IDF weights, the default value is 20
Withweight
that files are stored in the system at the beginning, but they are all stored in continuous blocks. However, some files are deleted after a while, leaving some blocks in the middle with no content, the adjacent block contains the content. In this way, there will be some gaps. Just like a few blank clothes are often taken out of the closet but not sorted out. If I want to put another dress in the closet, if
Prim
Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--># Include Template Void prim (int n, Type ** edge)
{
Type lowcost [maxint] = {0 };
Int closet [maxint] = {0 };
Bool s [maxint] = {0 };
S [1] = true;For (int I = 2; I {Lowcost [I] = edge [1] [I];Closet [I] = 1;S [1] = false;}For (int I = 1; I {Type min = INT_MAX;Int j = 1;For (int k = 2; k If (lowcost [k]
hdu1007http://acm.hdu.edu.cn/showproblem.php?pid=1007The key to solving problems: solving the algorithm of divide and conquer, paying attention to the method of divide and conquer1#include 2#include 3#include 4#include 5#include 6#include 7 #defineINF 0x3f3f3f3f8 using namespacestd;9typedefLong Longll;Ten structpoint{ One Doublex, y; A}p[100002],tmp[100002]; - DoubleDis (Point a,point b) { - returnsqrt ((a.x-b.x) * (a.x-b.x) + (A.Y-B.Y) * (a.y-b.y)); the } - BOOLCMP1 (Point a,point b) {
recall rate for the number of information that is related to the query value of the accuracy of the information to query the project of course, we want these two values to be as high as possible. So the index in each document and the corresponding recall rate and the accurate rate of valuation is the focus of our attention. But we need to pay extra attention to what part of speech we should choose to be indexed. It is obvious that words such as conjunctions, prepositions and so on should be
Score (Q,D) = Coord (q,d) querynorm (q) ∑ (TF (T in D) IDF (t) ^2 t.getboost () norm (t,d)) (∑: T in Q)D:documentT:termQ:queryCoor (q, D):public float coord (int overlap, int maxoverlap)Implemented as Overlap/maxoverlap.Overlap-the number of query terms matched in the documentMaxoverlap-the total number of terms in the query
Querynorm (q):public float querynorm (float sumofsquaredweights)Implemented as 1/SQRT (sumofsquaredweights).Sumofsquaredweights-
sidearm Shan blended 摜 摣 recruited name guarantees for stranded held stirring carrying 攄, 擯 Booth range scumbags captured enemy milk 攛 administration fight 攢 Time Kuang Yuang Cloudy daylight THROAT obviously Kuching herbs Hyo 曄 Dizzy FAI temporary TEM byronin The rustic machine kill the copyright Yang 榪 Jake structure Some stately fir centrum-櫪 梘 dealings gun Maple bossconn cabinet lemon 檉 梔 fences Mark Kushida 櫳 Nicholas Koroen 櫟 linked fields tree habitat like message â#̈ã branches 橈 ligustru
interface. Nested interfaces are used to group related interfaces so that they are easy to maintain. A nested interface must be referenced by an external interface or class. It cannot be accessed directly.Key points to remember for nested interfaces
A nested interface must be public when declared within an interface, but it can have any access modifier if it is declared within a class.
Nested interfaces are implicitly declared as static
Nested interfaces declare examples withi
not the same type of furniture storage, it seems that there is no other people put cutlery and clothes in the same closet. As with different types of data in the system, it is necessary to use the appropriate storage environment for different types of data. Files and pictures are stored, sorted first by the heat of the access, or by the size of the file. Strong relationship type and need to use the traditional database of transaction support, weak re
Http://linux.chinaunix.net/techdoc/system/2008/09/19/1033277.shtml
EXT2 file Localization Process simulation experiment (no theory version)Copyright:GnuAuthor Information:Alin Fang (Fang Yunlin)Msn:Cst05001@hotmail.comG Talk:[Email=cst05001%ef%bc%a0gmail.com]cst05001@[/email][Email=cst05001%ef%bc%a0gmail.com]gmail.com[/email]Bloghttp://www.alinblog.cnDate Modified:6 Aug, 2008Objective of the experiment:The purpose of making this note1. For the sake of forgetting2. To share with youTheory:The har
integrated wiring equipment and weak current room.The Integrated Wiring equipment room and weak current room include:IDC name;Purpose;China Telecom cabling data center;Cable access of telecom operators; (two access channels are provided );Weak Current room;IDF of floor distribution frame;Communication operators access data centers/DC network data centers;Communication operators access equipment rooms and network center equipment rooms (MDF );Hosting
the scores of the different queries.∑ (TF (T in D) IDF (t) ^2 t.getboost () lengthnorm (t,d))In parentheses, the fractional summation of each term parsed, for example: Query "Lucene and Solr", Lucene score + SOLR's score3.TF (termfreq), the frequency of the term in which the term appears in the documenttf = sqrt (number of occurrences of term in this document)/***/ @Override publicfloat tf (float freq) { return (float) math.sqrt (freq); }The m
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