Saturday, April 28, 2007
关于 SpringerLink 论文检索
一个实验经济学网站
EconPort is an economics digital library specializing in content that emphasizes the use of experiments in teaching and research. Content includes teaching modules, a handbook of economic and game theoretic principles and concepts, a glossary of economics terms, and an extensive collection of educational material, as well as software for running experiments. Teaching modules include: substantive coverage of a variety topics that are central to economics courses; instructions and guidance for professors who plan to use these experiments in class; suggested parameterizations for experiments; and graphical data presentation facilities. Integrated software includes applications for conducting game theory, market, and auction experiments. The content sections offered are:
Experiments - A framework that allows you to conduct a variety of online economics experiments.
Handbook - A virtual text of microeconomics closely tied to experiments.
Cataloged Resources - A cataloged collection of microeconomics resources that are available on the Internet.
Glossary - A collection of terms covering microeconomics, experimental economics, and econometrics, among other areas.
其中的 Handbook 部分讨论了与实验经济学有关的微观经济学经典理论，比如“不确定条件下的决策理论”。我是在 Google 关于期望效用理论（Expected Utility Theory, EUT）、Machina Triangle 的资料时发现了这个网站。
P.S. 那个“分类资源”中的好东西更多. :)
Thursday, April 26, 2007
一个学习概率的好地方
里面有关于概率的比较全面的教程和练习（含答案）。另外，还有相关定义和定理的索引。
并提供 PDF 格式的下载。初看起来，这些教程是采用测度论的语言描述的，比较抽象。但里面的很多知识在数理金融学中都有广泛应用，值得一读！事实上，该网站的作者正是一个在新加坡做衍生证券交易的博士。
PS. 网站里 Links 包含了更多数学（Math Links）和概率（Probability Links）方面的教程和资料，其中多数是 Free 的。
Wednesday, April 18, 2007
D-Link 504 路由器端口映射方法
Swarm 在 ArchLinux 上编译成功
已上传至AUR ：
http://aur.archlinux.org/packages.php?do_Details=1&ID=9938
linuxsir帖子地址：
http://www.linuxsir.org/bbs/showthread.php?t=296391
程序测试图：sss:
Wednesday, April 11, 2007
Gauss在中文系统下提示符消失的问题解决
方法1：不使用图形界面，改用 tgauss，即命令行界面。
方法2：直接从命令行输入：gauss.exe -prompt $，前提是 gauss.exe 须在系统路径PATH里。
方法3：更改 gauss 主程序快捷方式，在“属性”窗口中，更改“目标”为：E:\Gauss\gauss.exe -prompt $ 【假设 gauss 安装在 E:\Gauss】。
这样，gauss 启动后，提示符就变成 $ （注：这也是Linux中的默认提示符之一哦），而不是原来无法显示的两个箭头了。
Friday, April 6, 2007
BlogSpot.cpm 又被封了！
Thursday, April 5, 2007
QuantLib的Excel插件
http://quantlib.org/quantlibxl
可以在 Excel 中试用QuantLibXL的二进制包：
Download QuantLibXL-bin-0.4.0.exe from the Downloads page.
安装好后，会生成一个 Workbook 目录，里面有一些金融工具计算的例子。比如，swap、B-S 公式等等。
另外，Quantlib 还提供了与 Python、S-Plus/R、Matlab/Octave 等的绑定。详情参考其主页：
http://quantlib.org/
Wednesday, April 4, 2007
Python notes: 内置数据类型
1. Dictionary
Dictionary类型定义了key（键）与value（值）的一一对应。其中的元素就是键值对。Dictionary类似于Java中的Hashtable类的实例。注意，元素是无序的！key必须是不可变的数据类型，如字符串，整数，tuple等，但是不同类型可以混用。
2. List
List是Python中最常用的数据类型。与字典的元素无序不同，list中的元素是有序的。
List支持slice，可以很方便的取片（部分元素）。比如：
>>> li = ["a", "b", "kevin", "daisy", "shanghai", "z", "end"]向List中增加元素可以使用其方法：append，insert，extend等。其中特别要注意的是append与extend的区别：append可以接受任意数据类型的参数，将其追加到尾部。而extend只能接受一个list类型的参数，并将参数中的元素合并到原来的list中，新list的元素个数是两个list之元素个数之和。
>>> li[1:3] # 取第2~3个元素
>>> li[0:2] # 取第1~2个元素，其中0可以省略
>>> li[3:] # 取第3个之后的元素（不含第3个）
>>> li[:] # 取所有元素，即形成li的一个拷贝
在list中搜索：index可以返回某个元素的索引，如果出现多个相同的元素，则返回第一个出现的索引。要检查某个元素是否在list中，用in。
从list中删除元素：remove删除某个元素（只是首次出现的那个）。pop删除最后一个元素，并返回之。它与remove不同，remove并不返回删除的那个元素。
关于List还有一些运算符，比如 + ， 这个 + 可以连接两个list，且返回新list。它与extend不同，extend仅仅修改（扩展）了原来list，并不返回。因此，对于大型list，extend执行速度更快。还可以使用 += ，* 等，* 可以重复list，比如，
>>> li = [1,2] * 3 # 相当于 li = [1,2] + [1,2] + [1,2]3. Tuple
Tuple是一种不可变类型。和list一样，tuple中的元素是有序的，也支持slice。由于其只读属性，所以tuple没有任何方法。但是，如果只是对一列元素进行遍历，那么使用tuple比list更有效率。另外，tuple还可以作为dictionary的key（事实上，dictionary的key必须是不可变的，所以tuple可以胜任，而list不行）。tuple也可用于字符串格式化中。要注意，tuple和list是可以互相转化的：tuple函数冻结一个list，list函数解冻一个tuple。
关于这些数据类型的详细说明参见： Python Library Reference
关于数理金融和计算金融的几个网站
http://www.mathfinance.com/ - The bridge between investment banking and academic research in mathematical finance
http://www.wilmott.com - Paul Wilmott, 英国皇家学会会员, 2007年3月12日来财大演讲, 题目为“金融工具的日益复杂性” (The Growth in Complexity in Financial Instruments).
附：关于Wilmott Magazine的介绍：
https://secure.interscience.wiley.com/cgi-bin/jabout/98518264/ProductInformation.html
Aims and Scope
Independent, controversial and exciting, every two months Wilmott magazine brings you a valuable collection of papers, reports, and articles. Paul Wilmott and his team of expert contributors provide a unique mix of complex content and humor to inform and entertain analysts and academics alike.
Wilmott magazine offers you cutting-edge research, innovative models, new products, useful software, in-depth analysis, solutions, and the gossip behind them. We put to the test the latest quantitative finance theories with practical, jargon-free examples you can really use. It's the easiest way for you to keep up to date with quantitative analysis, the institutions, and the people who make it happen.
Compared to other serials in finance, the focus of Wilmott is on serving the quantitative finance community, and concentrates on practicalities.
Wilmott magazine publishes articles from all of the functional areas of quantitative finance. Papers are welcomed from quantitative analysts in banks and academia, mathematicians, econophysicists and economists.
We particularly welcome technical articles with a practical focus, on the subject of derivatives, risk management, finance, behavioral finance.
Articles in Wilmott will serve the advancement of the field of quantitative finance and the dissemination of useful pedagogical ideas. While the editors will consider articles of any level of sophistication, they will not be interested in technique for its own sake. In all cases, the idea behind an article must be closely associated with practical application.
Since the journal is published in six issues a year, publication is also rapid.
Send your articles in Word or LaTeX format to submit@wilmott.com.
利用OpenSSH和PuTTY实现Windows远程登录Linux
环境：ArchLinux-0.8/OpenSSH-4.6p1-1, WinXP/PuTTY-0.93
步骤：参考 http://www.centospub.com/make.html
1) 配置SSHD: 在用户认证方式上，为了服务器和用户的安全，禁止用户密码的认证方式，而基于“钥匙”的方式。 [密钥方式没有试成功，问题出在PuTTYGen转换密钥时，所以还是改用密码登录方式，下面的配置文件作相应修改！]
$ vi /etc/ssh/sshd_config
#Protocol 2,1 ← 找到此行将行头“#”删除，再将行末的“,1”删除，只允许SSH2方式的连接
Protocol 2 ← 修改后变为此状态，仅使用SSH2
#ServerKeyBits 768 ← 找到这一行，将行首的“#”去掉，并将768改为1024
ServerKeyBits 1024 ← 修改后变为此状态，将ServerKey强度改为1024比特
#PermitRootLogin yes ← 找到这一行，将行首的“#”去掉，并将yes改为no
PermitRootLogin no ← 修改后变为此状态，不允许用root进行登录
#PasswordAuthentication yes ← 找到这一行，将yes改为no
PasswordAuthentication no ← 修改后变为此状态，不允许密码方式的登录
#PermitEmptyPasswords no ← 找到此行将行头的“#”删除，不允许空密码登录
PermitEmptyPasswords no ← 修改后变为此状态，禁止空密码进行登录
2) 因为我们只想让SSH服务为管理系统提供方便，所以在不通过外网远程管理系统的情况下，只允许内网客户端通过SSH登录到服务器，以最大限度减少不安全因素。设置方法如下：
vi /etc/hosts.deny ← 修改屏蔽规则，在文尾添加相应行
sshd: ALL ← 添加这一行，屏蔽来自所有的SSH连接请求
vi /etc/hosts.allow ← 修改允许规则，在文尾添加相应行
sshd: 192.168.0. ← 添加这一行，只允许来自内网的SSH连接请求
3) /etc/rc.d/sshd restart 重新启动SSH服务
4) PuTTY远程SSH登录
下载：http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html
下载Windows installer安装，运行putty.exe,配置：
HostName：Linux主机IP，Port：22，connection type：SSH
在Translation中可以修改字符集，这里设为UTF-8
在Appearance中可以修改显示字体，这里设为Fixdays 12，cleartype，优化LCD显示。
设置完成后，可以save当前的配置。
Top 10 Linux console applications
Top 10 Linux console applications
http://applications.linux.com/article.pl?sid=05/04/20/2235237&tid=13&tid=86&tid=47
Tuesday April 26, 2005
System administrators regularly work from the command line, but there's more to the console than managing servers. You can do most desktop work from the console, and generally faster than you can accomplish work from a graphical user interface. You can even have a basic office suite, complete with a word processor, spreadsheet, and presentation program, all in the absence of a GUI. Here are 10 applications to try.
Screen
It may seem like cheating, but think of GNU Screen as a window manager for the console. I found it to be much more usable than the multiple TTYs normally spawned by Linux. Unlike the default virtual terminals, Screen allows you to begin with one shell or application and spawn new ones on demand. You can also start with a dozen or more predetermined applications as soon as you log in. Screen allows you to page between running shells and applications, cut and paste between them, log input and output from any session, and share consoles with other users or groups. When running locally, Screen can password-lock your console. Best of all, you can detach a shell or application running from Screen. As an example, using Screen I start with a top session. I then press Ctrl-a and then the d key. This detaches the top session. If I log out, then log in again a day later, my top session is still running. A simple screen -r is all it takes for me to bring it back to the foreground. That alone is reason enough for me to use Screen -- particularly for systems that I administer remotely.
Pine
Long before Outlook and Evolution there was Pine for handling email. This console-based email application was conceived in 1989 at the University of Washington in Seattle. It now supports LDAP searches and address books, exhaustive mail filtering and highlighting (with color coding), multiple POP and IMAP accounts, spellcheck, and MIME attachments through configuration of helper applications. The keystroke commands, though simple, may seem daunting at first, but the speed of the application makes mastering them well worth the effort. One of my favorite features is the default signature: "This message was written with Pine. Yes, that Pine."
Lynx
Lynx is a straightforward text Web browser that many Linux distributions include by default. It supports bookmarks, image viewing through helper applications, and color highlighting of URL links. Although Lynx does not display frames, it will allow you to select one frame from a frameset for viewing. I use Lynx in an xterm on my desktop for reading news and other interesting articles for which I don't have the patience to put up with popup ads, bad graphics, and moving advertisements.
Zed
I must admit that for console or xterm text processing I much prefer vi or Vim to any other CLI editor. In fact, I prefer Vim to many GUI-based word processors, and just as many people prefer Emacs. If, however, you would like something simpler, Zed is not a bad choice. It is small, fast, and provides many functions. Zed supports search and replace, multiple windows, macro programming, word wrap, text justification, and more. Although the default key sequences seem obscure, Zed provides for easy configuration of both menus and key sequences. I'd suggest it if you'd rather not learn vi or Emacs.
Oleo
I was frustrated with the Oleo spreadsheet application on more than one occasion. Some of that frustration was due to my own ignorance, as the key sequences are Emacs-based. As a Lotus, Excel, Gnumeric, and OpenOffice.org Calc user I had expected Oleo to be more intuitive, but I needed multiple sessions with the info file before I could use it proficiently. Even cell reference syntax was not what I had expected. As I became more familiar with it, however, I found a lot to recommend about this application. Oleo does not support the display of more than one file at a time, but Screen gives you a nice workaround for that limitation. It does support multiple windows of the same spreadsheet. It also supports macro programming, plotting through GNU plotutils (under X only) ASCII and PostScript output, and MySQL queries. A Motif GUI interface is available under X. Although it does not yet support most spreadsheet file formats, it works well on its own. If you are setting up a console office suite, it's an application that's well worth having.
TPP
The Text Presentation Tool (or Text PowerPoint) is an impressively flexible console-based application. It supports execution of external programs, background and text colors, ASCII text borders, and automatic page numbering and date display. Special effects such as fly in, fly out, slide in from right/left, and, to some extent, variable font sizes are also available. Each presentation comprises a plain ASCII text file consisting of text and simple commands. TPP also supports TeX conversion for printing. Even if you don't need it to round out your console office suite, you should try TPP as a means of annoying anyone who's ever sent you a 24MB PowerPoint file.
MySQL
MySQL ships with many versions and flavors of Linux. Although many X and HTML front ends are available for MySQL, it's just as easy to create and maintain a database from the command line. You can script commands and queries and call them with mysql < scriptname. This makes it easy to automate operations such as data imports and report generation. MySQL supports multilevel queries, output sorting and grouping, arithmetic operations, and much more. If you haven't used MySQL, you've overlooked one of the most powerful applications on your system.
Midnight Commander
Midnight Commander is a file manager and FTP client that looks and works much like Norton Commander for DOS. The two-panel interface can display two local directories, a local and remote FTP directory, a directory and file specifications, or a directory and file preview. File attributes and permissions are color-coded, and you can change them through Midnight Commander. In addition, MC supports file undeletion on ext2 filesystems. Although MC is not my personal favorite for file management at the command line interface, it is probably the most powerful.
ZGV
ZGV is an image viewer. Strictly speaking it is not console-based, as attempts to run it through an SSH session will display only on the remote system. In addition it requires the SVGA libraries, and does not work well with Screen, as it tends to take over the entire shell. As a standalone application, however, it is handy and powerful. It supports auto zoom, thumbnails, and slideshows. For work in the CLI it's possibly the best image viewer you can find. When exiting ZGV, however, the virtual terminal will sometimes stop responding. In these cases I've been able to fix the shell by switching to another virtual terminal and back.
Nethack
Nethack is a single-player multi-level dungeon exploration game. You must make your way through an enormous maze of enemies and monsters to find the Amulet of Yendor. It's possible to play for several hours a day for at least a week without completing this quest. You arrive in the dungeon as one of 13 characters with a faithful animal companion that will help you fight orcs, were-rats, and hundreds of other creatures. If you lose your companion, it may become feral and kill you later. Although there are hundreds of dungeon-crawl adventure games, Nethack is one of the best. It is possibly the most fun you can have without a graphics card, and its use of the vi key bindings make it an excellent training resource for vi and Vim.
Other programs
These applications are enough to get you started on your CLI-based system. If you enjoy the experience, here are a few more applications to try:
X-Chat-text -- IRC client
Tethereral -- front end for TCPdump
GNU Chess -- a chess game
Vlock -- a clock for the CLI
Halibut -- converts text to manpage, PDF, PostScript, and other formats
Cmatrix -- a screen saver
vifm -- my favorite file manager
ncftp -- FTP client
antiword -- converts Word .DOC files to text
Tuesday, April 3, 2007
New-to-Java Programming Center: Learning Path
With some C++ programming experience, you'll find the OOP concepts in Java programming easier for you to understand. You'll find Java programming similar in many ways to C++, but there are many differences as well. In addition, the Java class library is large, and you'll need to become familiar with it. The links below will help you learn the Java programming language syntax, as well as get you familiar with the class libraries:
New-to-Java Programming Center Supplement Learn the basics of the Java programming language and keep up-to-date on additions to the JDC's New-to-Java Programming Center with this new monthly supplement.
Trail: Learning the Java Language by Mary Campione and Kathy Walrath
From the Java Tutorial, this trail covers the fundamentals of programming in the Java language in an easy-to-use format. A must-read for anyone interested in learning this robust platform.
Essentials of the JavaTM Programming Language: A Hands-On Guide, Part 1 by Monica Pawlan
Learn how applications, applets, and servlets are similar and different, how to build a basic user interface that handles simple end user input, how to read data from and write data to files and databases, and how to send and receive data over the network.
Essentials of the JavaTM Programming Language: A Hands-On Guide, Part 2 by Monica Pawlan
Part II walks you through network communications, building a user interface using more components, data encryption and decryption (pseudo code only), grouping multiple data elements into one object (collections), and internationalizing a program.
The Java Tutorial by Mary Campione and Kathy Walrath
As part of the Java Series of books by Sun Microsystems, The Java Tutorial contains the Getting Started trail and six Trails covering the Basics. This book walks you through the process of writing a variety of useful applications with explanation and code samples.
Using Java Technologies An Interactive Menu
Learn how to use Java technology for desktop applications, applets, wireless devices, database connectivity, server communication, and more.
Learn How To Store Data in Objects by Jacob Weintraub; Reprinted from JavaWorld
This article delves into storing data in the Java programming language and the various ways you can use that data.
Books to Shorten Your Learning Curve by Dana Nourie
The right book for you depends on what you know. This article looks at some of the latest Java technology books, and who should read them.
Lesson: Solving Common Compiler and Interpreter Problems by Mary Campione and Kathy Walrath
Having trouble compiling your source code? This lesson from the Java Tutorial outlines the most common compiler and interpreter problems.
Also, check the Reference and Resources page for the Java API documentation, as well as other articles of interest on the Step-by-Step Programming page.