Math Open Reference


About the advertising on Math Open Reference
A note from the author

Advertising is the sole financial support of Math Open Reference. Like many sites on the web, it is administered by the Google Adsense program. I do not select the ads that run on the site, although I do have some general control over them. I can set filters and block specific advertisers.

How it works

Each web page has blank areas that will later be filled with ads. When your browser fetches a page form Math Open Reference, it arrives at your device with those areas still blank. Just before the page is displayed, scripts in the page are run by your browser which request ads from Google. These ads arrive from the Google servers (not ours) and are filled into the blank spaces. The page is then displayed. This all happens very fast - usually in a second or so.

How are the ads selected?

Google selects ads that you will see based on many criteria. For example, your past searches, time of day, and your geographic location. It then looks at filters that Math Open Reference has set that are designed to remove ads that are not appropriate or may be offensive. Then the Google system conducts an instantaneous auction to see who will bid for the ads slots. From these it selects the ads that will be sent to you. In some ways, it is quite astonishing that all this happens while the page you requested is loading.

I do not see the same ads that you do

When I look at the web site, I see ads that Google has selected that it thinks will be appropriate for me. You will see a different set.

What to do about inappropriate ads

It should not happen much, but some advertisers sometimes find a way to sneak something past our filters. If that happens, first accept my apologies. Click on the ad and see what the web address is of the advertiser and send it to me. I have a tool on the Google system that lets me block specific advertisers. So for example you may see an ad that takes you to www.slimandtrim.com/this/that. I can block all ads from that advertiser. But you have to tell me. I do not see the same ads you are seeing, so the only way I can block them is if you tell me.

Can I block the ads?

Yes. There are several tools that you can install on the machine that will block the ads. For example Adblocker. Also most schools have filters on the internet connection that removes them. We try and make sure all these tools will work properly with this site, but there are many to keep track of.

Send a message to the author