Googling to the. Introduction to Google. Part 1 Search Techniques and Tips

Transcription

1 Introduction to Google Part 1 Search Techniques and Tips Welcome to Max part 1 search techniques and tips. In this section, I will cover the basics of searching with Google and introduce you to some more advanced techniques that will get you on the road to becoming expert searchers. 1

2 Joe Barker John Kupersmith A Know Your Library Workshop Teaching Library, University of California, Berkeley Fall 2005 The information in this tutorial was adapted from a workshop designed by Joe Barker and John Kupersmith at the University of California at Berkeley. The slide format and the basic material in this online course is used with their permission. Supplemental details were found in the book Google: the missing Manual by Sarah Mill-steen and Ray-el Dornfest. 2

3 Goals and Objectives Learn why Google is the most popular search engine Learn how Google works Learn how to craft useful searches The Goals and objectives for this section of the course are to Learn why Google is the most popular search engine Learn how Google works Learn how to craft useful searches 3

4 Why Google? Biggest web search engine database 22+ billion pages Unique PageRank system Many useful features, shortcuts, and special Google databases & services NOTE: POWERPOINT IS SET TO CLICK EACH LINE. CAMTASIA FILM NOTE BE CAREFUL Why use Google? Google is currently the biggest web search engine database. It searches over 22 billion pages Google uses a unique algorithm called a PageRank system to get targeted results for your search queries. I ll explain PageRank in more detail later. Finally, Google offers many useful features, shortcuts and special databases and services. These will be covered in other sections of this course. 4

5 What s? Crafting searches likely to work Knowing how Google thinks about your searches Exploiting Google s strengths and weaknesses Knowing what Google s special features and databases can do for you NOTE: POWERPOINT IS SET TO CLICK EACH LINE. CAMTASIA FILM NOTE BE CAREFUL What is? is knowing how google thinks so that you can create searches that are going to work best for your needs. is knowing how to exploit Google s strengths and weaknesses (yes Google does have a few weaknesses!) is also knowing how to access and use Google s special features and databases. The special features and databases will be highlighted in another part of this course. 5

6 How Google works Spider program finds pages on the public web; builds huge database of web pages The Search box gives you ways to search this database PageRank arranges your results Importance - traffic, popularity of pages linking to a page Popularity - a link to a page is a vote for it Word proximity and placement NOTE: POWERPOINT IS SET TO CLICK EACH LINE. CAMTASIA FILM NOTE BE CAREFUL How Google works A spider program finds pages on the public web and builds a huge database from the web pages. Wordnet defines a spider as a computer program that prowls the internet looking for publicly accessible resources that can be added to a database The familiar search box on Google s home page gives users a way to search this database by entering search terms and symbols that act as search limiters. Google s unique pagerank system decides how the results should be organized for display. The page rank system looks at a number of things First it looks at the links going to a particular page and considers those links to be like votes. For example, if you do a search for stamp collecting one page that consistently is at or near the top of the hit list is There are many pages that link to so it got lots of votes according to 6

7 The Google Search Interface Here is Google s home page. When you go to this page, at the default setting is for a general Web search. Other options that are possible from the home page screen include images, videos, news and maps. There are also links for more search options, advanced searching, preference settings and Language tools. In this section of the course, I will be concentrating just on Web searching. See section four of this course of information about Advanced Searching, Preference Settings and Language Tools. See Section three for searching images, videos, news, maps and more. In section four, I will introduce you to some new projects that Google has in the works as well as some fun with Google. 7

8 How Google Thinks AND Is automatically implied between search terms in the search box Is automatically implied when searching text of pages within the same site Example: california vacation anaheim So far, you ve learned a bit about how google works behind the scenes. Now we re going to start talking bout how google thinks. Knowing how google thinks will help you understand how to get faster, more accurate results from your searches. First, when you enter two or more words into google s search box, it automatically assumes that you mean AND between each of your search terms. For example, if you enter the words california vacation anaheim it is the same thing as entering california AND vacation AND anaheim. In fact if you type and in between each term, google gives you the following message: The "AND" operator is unnecessary -- we include all search terms by default 8

9 How Google Thinks It STEMS some words It finds word with various endings Search kite flying and get matches on kite, kites, kiting and flying, fly, flies You can turn off stemming by using + or as in +kite +flying or kite flying Google stems words to allow for various endings and verb tenses. If you search for kite flying, you will get results that show the words kite, kites, kiting, flying, fly and flies. If you don t want google to stem your words, you can tell it not to do that. A plus sign forces google to just search for that specific term. If you only want to search the for the word kite or the term kite flying you can use a plus sign or quotes to make your search very specific. In the example on the screen, the searcher wanted the specific words kite and flying or the specific phrase kite flying. To force specific words, use the plus sign in front of the word. Make sure you don t put a space between the plus sign and the word. To find a specific phrase, use quotes around the phrase. Quotes are often called a searchers best friend. You can get very targeted results using this technique. For some fun, try using quotes in a vanity search that is searching for your own name on the Internet. Put your name (or that of someone you know in quotes) in the Google search box and see if you can find yourself on the Internet you may be surprised by what you find! 9

10 How Google Thinks It IGNORES common or STOP words When this happens, a gray message box appears just below the search box which tells you what was ignored You can force Google to look for stop words by using the + sign or putting the word(s) in quotes Examples of stop words include the, and, or, where, this, who, with, for, from Google ignores common words, also called stop words in database and internet searches. Stop words don t stop the search, they are just ignored. Notice that and is stop word. Remember that AND is implied in searches; you don t need to use this word to join search terms together. A few stop words are the, and, or, where, this, who, with, for and from. Remember, this is not an allinclusive list. You will discover other stop words in your searches. Before we leave this screen, I want to point out that or in lowercase letters is considered a stop word. When OR is in uppercase letters, it is considered a Boolean search term. Go next screen for an explanation of when to use uppercase OR. 10

11 How Google Thinks Using OR between words can broaden your search California OR oregon OR pacific coast global warming OR greenhouse effect Google uses the Boolean OR search to broaden search terms. As I mentioned on the previous slide, or is on the list of stop words. That s because when or is in small letters it is ignored; when it is in capital letters it helps define a search by making it broader. When you use or, you are telling Google to search for this OR that. This is particularly helpful when several terms that mean roughly the same thing, as in the global warming OR greenhouse effect. AND and OR are two Boolean search terms. Google doesn t support full Boolean searching For more information about about this topic, see the Boolean Searching tutorial in the LATI website. 11

12 How Google Ranks Pages RANKING favors pages that have your phrases close together and in the order typed. So, with Google, the order in which you place your words for searching really does matter. (see next two slides for examples) Google s ranking system favors pages that have your phrases close together and in the order typed. So with Google, the order in which you place your words for searching really does matter. The next two slides show some examples. 12

13 Example Searches Grass snake mostly about a kind of snake; stemming also matches snakes and grasses Snake grass mostly about a kind of grass, not present in 1 st search Snake in the grass most pages contain this expression, even though Google said in and the were ignored; also finds pages with grass snake and a few with snake grass (cont.) If you search for Grass Snake, your results will mostly be about a kind of snake. Google s stemming feature will also match those words to snakes and grasses. If you search for Snake Grass, your results will mostly be about a kind of grass. If you search for the words snake in the grass, most of the pages do contain this complete expression, even though google said that in and the were ignored. It also finds pages with grass snake and a few with snake grass. 13

14 Example Searches Cont. Snake +in +the grass eliminates pages not containing in and the somewhere snake in the grass Most specific and precise. Requires exact phrase in all pages. If you force google to include the stop words in and the, it will eliminate pages not containing in and the somewhere. Since most pages contain these words, this type of search probably won t get you the best results for what you are looking for. By putting quotes around snake in the grass, you will get much more precise search results than you would in the previous example. This search requires that this exact phrase occur in all pages. Quotes are sometimes referred to as a searcher s best friend. they are often the best, most direct way of finding accurate results when using a search engine or searching in a database. 14

15 Punctuation that is Not Ignored Apostrophe peoples, people s and peoples are searched as different words Hyphen same-sex retrieves same-sex, same sex and samesex Accent marks in foreign languages éléphant doesn t match elephant Asterisk this is a whole word wildcard. Google doesn t have a wildcard that substitutes for single letter(s) If your search term has an apostrophe in it, first try entering it exactly. If you don t find what you are looking for, try entering it without the apostrophe-- you will get different results. With hyphenated words, google will look for words with the hyphen, without the hyphen and also compound words that combine the hyphenated words together. Google treats accented letters as different symbols. It will not match a word with accents to one without. An asterisk is a wild card symbol that substitutes for a whole word. Google doesn t have a wildcard for single letters. 15

16 Fuzzy Thinking Search Options Tilde (~) Google will think of words with similar meanings ~food matches recipes, nutrition, cooking ~facts matches information, statistics ~help matches guide, tutorial, FAQ, manual If you aren t sure which is the best search term to use, you might try using Google s fuzzy logic feature. If you put a tilde [til-duh] in front of your search term, it will think of words with similar meanings. This is particularly helpful when you are trying to narrow down very general searches as in the examples shown here. 16

17 Similar Pages Google will think of pages like the one you chose. You can use the similar pages link, or force it to look for similar pages with the related: [URL] command Related: will bring up pages for CNN, New York Times, MSNBC, Fox News, etc. Google will think of pages like the one you choose by using links to and from the page, words in the page and the importance of the pages in links Possible uses for this include evaluating web pages, finding comparable pages and broadening searches by seeing what else links to a particular website. When using the related colon search limiter, don t put any space between the colon and the url. 17

18 Searching Specific Sections of Web Pages Intitle:searchterm-- Words must occur in the official title field of the page Example: Intitle:mileage This searches for the term mileage in the page title The intitle search limiter forces google to look for your search term in the official title field of the page. (By title field, I am referring title field in the HTML coding, but for most purposes this is also the title that appears on the web page). A Google search for the term mileage without the intitle limiter results in 59 million hits By using the intitle limiter, you focus your search and narrow your results considerably. When I did an intitle: mileage search, I got 648,000 hits. 18

19 Searching Specific Sections of Web Pages site:searchterm limits your search to a particular site. site: global warming OR greenhouse effect This searches just the official white house site for information that includes the terms global warming or greenhouse effect. The Site: limiter limits your search to a particular website. When you use the site search, remember to include both the site that you want to search and the search term or terms that you are looking for. The sample search on this slide searches just the official white house site for information that includes the terms global warming or greenhouse effect. 19

20 Searching Specific Sections of Web Pages Inurl:searchterm searches for results that contain your searchterm within the URL (web address) inurl:lincoln "gettysburg This searches for the term gettysburg in any web address that contains the term lincoln. Sample result: The inurl search limiter forces google to search just within the URL which stands for Uniform Resource Locator by the way also known as the web address. In the example on this slide, google searches for the term gettysburg in any web address that contains the term lincoln. See the sample result to see how this search might work. 20

21 Searching Specific Sections of Web Pages But wait there s more! Intitle:, inurl: and site: are just three examples of specialized searches that you can do. You can also search within the text of documents or look for specific file types (.pdf, powerpoint,.word docs, etc.). You can also mix your searches and tell Google to eliminate some things from your search. For more information, see the resources listed at the end of this presentation. 21

22 Weaknesses of Google Google doesn t support the full use of Boolean search terms It only indexes the first 101k of a web page Doesn t allow for truncation Isn t good for most deep web searches. 10 word limit for searches Google does have a few weaknesses. It doesn t support full boolean searching. You can only make use of the default AND, the forced AND and the OR terms in your search. It only indexes the first 101 kilobytes of a web page. Another search engine, Yahoo for example, indexes up to 500 kilobytes in the text of web pages. Although it does stem words, it doesn t allow for truncation. You can t put in part of a word and get Google to guess the rest. Although if you misspell a word, or enter a strange word, it will often ask you if you really mean something else and take a guess as to what you might really be looking for. Google isn t good for most deep web searches, which is why libraries subscribe to unique databases. However, google is improving in some specialized areas such as google scholar which searches scholarly document, google book search which searches the full text of thousands of books and find in a library which searches the OCLC database. OCLC stands for online computer library center and is a worldwide library cooperative. Google has a 10 word limit for searches, but you probably won t run into this limitation too often. 22

23 Other Google Tips The first search term is the most important Google search box is also a calculator Google can be used as a converter for measurements and currency Google can be used as a dictionary (define:) And many more Google considers the first word you give it to be the most important. A search for the terms library maryland brings up different results than Maryland library. The google search box can be used as a calculator, a mathematical converter and a dictionary. It can also be used to find airport conditions, track airline flights, find stock information, look up information in white and yellow pages and get movie listings for your home location. With google you can also track packages from UPS, FedEX and the US Postal service. You can look up Universal product codes and VIN numbers to get vehicle information. All of these special services will be explained in greater detail in Part 2 of this course. 23

24 For More Information Google: The Missing Manual by Sarah Milstein and Rael Dornfest Web Search Garage by Tara Calishain The UC Berkeley website excellent tutorials and info about searching the Internet-- Guides/Internet/FindInfo.html For more information check out these resources. Google also has excellent explanations of its services throughout it s web site. 24

25 What s next Congratulations! You ve completed part one of this online Google training course. Practice some of the things you ve learned before moving on to part two, Google Tools and Shortcuts. 25