(I just noticed OP is the author, so I'll put my comment here) [edit : correction, OP is the author's brother, sorry :]
I'm absolutely no mailing specialist, but here is my take :
Your study is quite interesting, but has it any value without you saying which mails your read when ?
Tracking if an email has been read or not is quite simple, providing the email is sent as HTML and the one who reads it is no privacy-nerd (noscript, ghostery, other ways to block external ressources, highly secure mailbox softwares, etc). What if you regularly "read" Obama's mails and not Romney's ones ?
If I were to manage this kind of mailing campain, I'd probably put on hold for a while email addresses who haven't read the last X mails. On the contrary, I would go on sending mails to people reading them. Etc.
Please tell us what you did "read" and when, and what you did not.
The one I use does, yes, and probably most of them do. And I really like this feature. But I'm certain that if I wanted to support a candidate and subscribed to his newsletter, I would allow all images from sender because I would want to see the pictures, or just because the newsletter layout looks better with images.
And people managing these kind of newsletters probably know that. They design nice layouts for their newsletters, with images and fancy stuff to be "visually friendly". And they know people will want to let pictures in, and they know they will then have the possibility to track views. They even include the infamous if this email isn't properly displayed, see it here [http: //link/mail/online/?here_is_who_clicked_this_link=your_name] (usually more subtle than that.)
I was testing out mailchimp the other day, and I could not for the life of me get the thing to recognize that I had read my test e-mails to my accounts, even though I had.
It's a great call - I'll post a follow-up with that detail and try to find a couple other examples from people in other geographies and demographics. My take (from this exercise and looking at ProPublica's data) is that behavior varies significantly based on both WHO campaigns think you are and WHAT you've done lately (what you've read, which sites you've visited, have you donated or volunteered, etc).
This complexity is going to make analysis nearly impossible in the future as political (and marketing) messaging becomes incredibly personalized.
(I'm actually author and OP here is my also-HN reading brother who beat me to the punch)
I'm absolutely no mailing specialist, but here is my take :
Your study is quite interesting, but has it any value without you saying which mails your read when ?
Tracking if an email has been read or not is quite simple, providing the email is sent as HTML and the one who reads it is no privacy-nerd (noscript, ghostery, other ways to block external ressources, highly secure mailbox softwares, etc). What if you regularly "read" Obama's mails and not Romney's ones ?
If I were to manage this kind of mailing campain, I'd probably put on hold for a while email addresses who haven't read the last X mails. On the contrary, I would go on sending mails to people reading them. Etc.
Please tell us what you did "read" and when, and what you did not.