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Design #1 Analysis:

Learnability:

Efficiency:

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The biggest benefit to using this design is that all users, whether they are invitees or event admins, need not have an account or manage contacts or other personal information. This design provides all event communication through email and hyperlinks which are an already familiar tool to most people. This is particularly convenient for our user group, working adults, because email and internet access is typically something that is at hand. For this design, one will only need to visit the site when he/she wants to create a new lunch event.

Efficiency:

For the learnability benefits that come with no accounts or user contacts, the price is paid in efficiency. Although one does save the time required to maintain and organize contacts as well as the time it takes to check an outside webpage, the application keeps no information for repeat users. Specifically, when an event creator needs to send invitations, every time he/she creates a new event, he/she will be required to type his/her own name and email as well as the names and emails of all invitees.  Secondly, this design does not provide any central browsing, meaning that all interaction with created events is done through hyperlinks in emails. The problem here is that invitees and admins depend on the organization of their emails for quick access to the link that goes to the details page. This link could quickly get buried in emails.

Safety:

A big safety risk with this design is in the means by which the admin invites other people. On the 'invite guests' page, the creator is required to input email addresses for invitees. If any of these addresses are mistyped, the application has no way of indicating this to the user before attempting to send the invitation and then receiving a failure notice(which takes time). Because this is done through email, the the users of this design don't have to worry about losing a password, or having an account hacked, but do run the risk of misplacing an event link. This is the only way an admin or invitee can access the page, so if it is lost, it is difficult to recover.

Design #2 : Lunch List Browsing Interface

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