NBER Working Papers Download FAQ

What does the facility offer?

Visitors to the NBER Web working papers site, at http://www.nber.org/wwp.html are able to view and download the full text of papers in Adobe PDF format.

Are all papers included?

All papers back to June 1973 or numbered 0001 and higher are available online. Select here to learn the highest numbered (latest) paper currently available online.

Is it free?

Full-text down loads are free for subscribers to the hard copy series, journalists, corporate donors to the NBER, US sites with domain names in ``.GOV'' and residents of developing countries and transition economies. Online only subscriptions are also available at half the regular or university subscription price. Individual papers can also be downloaded for a small charge for users not in any of these categories. For more information on all these modes of access, select on the help link at the end of this page.

What do I need at my end?

Any World Wide Web browser (even character mode browsers) should do for downloading. To view or print the papers you would need the free Adobe Reader.

How do I get authorized for free downloads?

Access for US sites with domain names in ".GOV" should be automatic. Access for developing countries should also be automatic, based on the 2-letter top level domain name. Subscribers will need to send their domain name and network number to wwp@nber.org together with with the subscriber number on the label of any working paper received as part of their subscription. Journalists and corporate donors should write to wwp@nber.org respectively with the network identification information.

How do single copy sales work?

On the bibliography page shown to non-subscribers there is an 'Purchase From SSRN.com' button. You can select that to order an electronic copy via the browser. You will need to provide a credit card number to effect the transaction. Currently the charge is $US5 for each paper downloaded.

Is a network number the same as my IP address?

Not exactly. The network number covers all the computers on your subnet, possibly the whole university or firm. Your IP address is only one address among the many in use at your site. The online working papers are offered to the whole site, not just your computer.

Do I really need to know the network number?

If your network Domain Name Server can correctly resolve reverse name lookups, the network number is redundant. It may help to explain how we authenticate users. With every WWW query, we are provided with the IP address of the querying computer. We then compare that to the list of network numbers, and if the IP address is on one of the authorized networks, we offer a full-text down load. Otherwise we do a reverse lookup on the IP address. If that returns with the host name of a machine in an authorized domain, the full-text down load is offered. Only if both attempts at authentication fail is the down loading opportunity not offered. Any user not offered a free download on the bibliographic page is offered a purchase button, and also a link for Users expecting free downloads.... If you select on the later, you will be asked for your email address. We will do our authorization checking on that address, and email you a special URL to download the paper if the email address is in an authorized domain.

Whose fault is it if reverse name lookups don't work?

Your ISP, network administrator, or whoever is responsible for your name server, or possibly your firewall administrator, or even a poorly designed security policy. Lookups might fail also on a very overloaded network - this would be temporary.

How do I know if my domain name has been entered in your database?

Try browsing http://www.nber.org/papers/w0000 to test your status. . You can test your network for reverse name lookups with the reverse-lookup tester from Digital. Much more information about reverse name lookup is available from http://papers.nber.org/reverse.shtml which includes our observation of the host name and IP address of your system. If you have any difficulty obtaining authorized access, please send us that information.

We use a Web proxy server or firewall that hides our address. Can we participate?

If the proxy server or firewall is part of your domain, there is no problem. If it is shared by other customers of your ISP, or otherwise combines the requests of multiple sites, we may not recognize the requests as coming from you, in which case we will not offer free access. There are various ways of overcoming this difficulty, but your network administrator needs to discuss them with feenberg at nber dot org to select the best way. We are quite flexible and can authorize off of VIA or X-FORWARDED FOR headers if those can be supplied by the proxy.

Our provider is Compuserve/AOL/Worldnet/... and I don't know my network number. Can we participate?

Select here for information about our provisions for you. This information is also usefull for users who travel, or wish to download working papers at home.

Our system gets a different IP address every time it connects. What should we do?

If the selection of addresses is from a pool restricted to your firm or university, then your network administrator should be able to tell you the network number range from which individual assignments are made. If the IP addresses are assigned by a large ISP which serves many customers, then see the answer to the previous question.

Where do I find the papers?

Browse http://www.nber.org/wwp.html for a general user interface. If you know the working paper number you can retrieve the abstract and bibliograpy page with http://papers.nber.org/papers/wNNNN, where NNNN is the working paper number. You can directly retrieve the paper itself, in .pdf format with http://papers.nber.org/papers/wNNNN.pdf.

Why does it take so long to download a paper?

The papers are mostly images of printed pages - not character data. This makes most working paper files 1 or 2 megabytes in size, quite large for someone with a modem connection, but practical for a hardwired link. We expect to provide more compact file sizes for future papers. Overseas users sometimes have difficulties because of overloaded trans-oceanic backbones.

Now that I am authorized, what more can go wrong?


An extensive list of possible problems is given in our trouble-shooting page.

If you still need help, send an email message to wwp@nber.org with the host name and/or IP address of the computer you are using, the number of the working paper you are having difficulty with, and the time of the failure (Eastern Standard Time). Also, try looking up paper number w0000, and note if that is successful. I can examine the log and perhaps diagnose the problem, or save it for our programmer. Without the paper number and time, there is very little I can do.

Last modified 27 February 1999
feenberg at nber dot org


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