Best way to enter/display relative time in a text box

Question

In a reporting client I'm working on now, there is a need to filter data by different conditions, among which are conditions based on date/time. Decided, that user first selects a predicate from a drop-down menu, then enters an absolute or relative date/time value in a textbox.

My issue concerns relative date/time values. Suggestion is to use shortcuts (d, h, m) for value and sign (- or +) to indicate in which direction it should be shifted from now.

For example, if now is 15:45,

• [earlier than] [ -3h] -- means "up to 12:45"
• [ later than] [ -2h] -- means "starting from 13:45"
• [earlier than] [ +2h] -- means "up to 17:45"
• [ later than] [ +1h] -- means "starting from 16:45"

Is my approach obvious and easy to understand? Are there some other common ways to solve this issue?

If user enters a value without sign, how it should be treated?

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The main use-case is the following: first a user sets up all conditions, then saves the whole filter for further usage. Filters are created once after installing and sometimes when a user needs some specific report. Saved filters can be modified, but this won't happen often--maybe once a day or a week. Users are enterprise, not wide audience, so some sort of training/tutorial will be provided.

Answer 1

Personally, I have to say I find the plus and minus symbols somewhat unintuitive... to me, "earlier than minus 2 hours" is a double negative that combines to mean "later than 2 hours", or something :)

Are you restricted to two fields? With a second dropdown at the end, you could be more explicit, e.g.:

[up to ]      [ 3h] [ago]      -- means "up to 12:45"
[up to ]      [ 2h] [from now] -- means "up to 17:45"
[later than ] [ 2h] [ago]      -- means "starting from 13:45"
[later than ] [ 1h] [from now] -- means "starting from 16:45"

Be aware however that all UIs like this can raise localisation difficulties due to different word ordering and the nuances of describing time periods in different languages, if that's an issue for this particular application.

Answer 2

For controls used rarely, explicit is better than implicit

• If this widget were being used 100x a day, the answer might be an expert interface where the user can enter values like 10h8m, 1d23h5m etc.

• But, this is not your use case. You have stated that this widget will be used very rarely. In this case, it's much more important to make the interface clear than to make it fast.

• Here's an approach which uses a combination of explicit controls, labels, instructions, default values, and confirmation to ensure that users understand how to use the widget and what the result is:

Answer 3

I think its a hard question to form one answer to.

Pure theoretically, I'd suggest not to rely on the user to know these abbreviatons like h,d,s,... or at least try to lower some cognitive load by explaining the use cleary (as Don Norman likes to call it, put the knowledge in the world instead of in the head). From the moment you introduce a syntax (like +/-/d/h/m/s/...) you should be very aware of the caveats this brings.

If you'd ask me, i'd add a range slider instead, so it behaves something like this crude example:

Perhaps its best to A/B test this with a few people and watch whatever comes more naturally. Also interesting to know the whys and whats:

• why do you want to use the "now" as your base, as the future is unknown at that point?
• What happens when you want to select a range of dates?
• Why do they want to set a range in such a fine granularity?
• What is the exact problem that needs to be solved?

Answering these questions first could perhaps help you discover a better answer :-)

Kind regards

Answer 4

I suggest abandon using +/- way of doing this, but try to use start date and end date approach, but with relative dates:

[start date][2d ago][end date][now] --> means "analyse last 2 days"
[start date][undefined][end date][3h ago] --> means "analyse all data that arrived not later than 3 hours ago"
[start date][2d ago][end date][3h ago] --> means "analyse data that arrived later than 2 days ago but not later than 3 hours ago"
[start date][2d ago][end date][5h from now] --> means "analyse data that arrived later than 2 days ago but will not arrive later than 5 hours from now"
[start date][2h from now][end date][undefined] --> means "start report 2h from now and keep getting data (?)" 

Are you sure user needs this future relative time? Maybe you could abandon this to make the whole thing more clear?

Answer 5

I think your current approach carries a hefty cognitive load. You're anticipating the user being able to understand:

• That the scale is relative to the time right now
• That using a + or - alters the start or stop based on the time right now
• That they can specify time in days, hours and minutes with d/h/m

Using your system, if I wanted a report that ended yesterday at 03:00 and right now it's 11:40 I would say: [Earlier Than] [-1d8h40m]. And that took me half a minute to calculate in my head.

People using your system might need very precise control, but humans are not very good at calculating differences in their brain. For example, telling you I need a project completed in 18 hours requires more cognitive load on your part to figure out exactly when I need it done. It would be easier for me to just tell you I need a project done at 06:40 tomorrow.

So for your system, let the user pick the day, hour and minute a report needs to start or end. It could be as simple as 3 dropdowns, one for each category (with minutes broken into 10 or 15 minute increments), and then an option to toggle whether it's when a report starts or ends. And you could further simplify by having the 'day' field default to the current date or even text that says 'today.'