Economics and Business Information Analysis

Transcription

1 Economics and Business Information Analysis Lecture 3: Main features of empirical ii analysis of economics and business information - Search Lecture 3: Main features of empirical analysis of economics and business information: Search Main concepts: Search Keywords Search methods Search tools Results assessment Information sources Topics: 1. Search: methods and tools 2. Search: internet, search engines, library catalogue 3. Main statistical information sources: National Statistical Office; Bank of Portugal; Ministries; Eurostat 4. Assignment Examples to be used: search assignment Exercises: search assignment Bibliography: 1

2 Search the internet for economists - Search options - Addresses - Directories - Search engines - Meta search engines - Meta search programmes 2

3 Directories Thematic classifications of internet resources Examples: Yahoo, Sapo You follow a tree you start from a generic theme and you keep going into particular sub themes trying to find the specific them that contains the issue you are trying to find yellow pages You depend on who has made the thematic classification They are quite useful for generic questions but do not give good results for very specific searches Many times they include search engines Search engines Allow you to find pages that contain the keyword used Example: Google Usually they use a data base with pages indexed when the user performs a search the data base is consulted and a results page with all the links is prepared they are quite useful when you want to perform a specific search but they give hundreds of results when the user is very general in the question it poses 3

4 Meta search engines They perform our search in several search engines and put the results together. Example: Metacrawler Advantages Avoid repeated results Disadvantages loose information and specificity syntax is many times more complex Many times some functions not available do not allow to perform complex and specific searches Meta search and intelligent agents Meta search software programmes computer software thatt is installed in our computer and replaces meta search engines some difficulties in translating our questions to all search engines they consult many times better prepared to search within a data base Intelligent agents or bots - some new software programmes that are not devoted to search but that you can use in search for instance periodic or regular search Music search 4

5 Search operators Allow to perform searches using more than one keyword non boolean boolean filters (Operators and syntax may change from one engine to another) Non Boolean Operators +: find sites that must contain the given keyword -: find sites that do not contain a given keyword *,?, %: wildcards to search word variants to find expressions Search operators Boolean logical conditions AND, OR NOT Parentheses to aggregate operators NEAR, BEFORE, AFTER. Filter to fine tuning search title url: Uniform Resource Locator, domain: electronic name of a computer, firm, institution, country or domain host: the computer that hosts the web page site: link: the URL of web pages that have links to a given webpage 5

6 Evaluating search results we must assess results quality is not enough to have results Some criteria How actual is the information Quality of the source it has reputation? Is a commercial firm with specific interests? Accuracy (Be careful with some eventual interests underlying web pages) Check Ci Criteriai for Evaluation of Internet Information Resources (VUW) - Evaluating Web Pages (Univ. Berkeley) - 6