This is a guide for students attempting Human Computer Interaction in digital technologies achievement standard 1.44 (AS91074).
In order to fully cover the standard, you will also need to have done projects covering the topics of Algorithms and Programming Languages, and included these in your report.
Human Computer Interaction has the following bullet points in achievement standard 1.44, which this guide covers.
Achieved: “describing the role of a user interface and factors that contribute to its usability”
Merit: “explaining how different factors of a user interface contribute to its usability”
Excellence: “discussing how different factors of a user interface contribute to its usability by comparing and contrasting related interfaces”
As with all externally assessed reports, you should base your explanations around personalised examples, so that the marker can be confident that your report is your own work.
You should read and work through the interactives in the following sections of the CS Field Guide in order to prepare yourself for the assessed project.
Start by reading both of these introduction sections. They will give you a general overview of what Human Computer Interaction is all about.
Then read one (or both if you're keen) of these sections on usability, in order to understand the kinds of things you will be looking for in your usability evaluation.
In this project, you will carry out a usability evaluation by observing a helper carry out a specific task on an interface you have chosen. While you could theoretically do the task yourself and write down where you had difficulty, it is surprisingly challenging to notice and be objective of usability issues you are facing yourself.
It is essential that the interface you choose is one that your helper is not already familiar with.
Because you will need to compare related interfaces for excellence, make sure you choose an interface for which you will also be able to find a second related interface to compare with (e.g. two different alarm clocks or two different flight booking systems). The second interface should also be one that your helper is not familiar with (otherwise they may be biased towards the one they are familiar with).
In addition to choosing interfaces, you should also choose a specific piece of functionality within the interfaces. For example, the texting capabilities of a cellphone, file chooser on a computer, or drawing a simple picture in a drawing app. Focussing on something like "iPhone vs Samsung Phone", or "Windows vs Macintosh" are too general as there are thousands, if not millions, of aspects to those interfaces. You would need to pick specific apps or programs within them, and then a specific piece of functionality within the apps or programs.
Some possible pairs of interfaces you could use are: (Although remember that this list is far from exhaustive)
- Online booking systems for two different airlines (e.g. Air NZ vs Jetstar).
- Two different friends' cell phones.
- Two different email clients you have never used before (don’t forget about the many webmail clients. Even signing up for webmail addresses could prove to be challenging in some cases).
- Two different microwaves. Cheap microwaves are notorious for being inconsistent and illogical to use. [Note that running a microwave with nothing in it will damage it! You would be best to put something inside it while you are experimenting with its interface. Water in a microwave safe glass is fine]
- Two different apps/ programs/ for setting an alarm (many exist). You could choose ones that go on a phone or on your computer, or one of each. A physical alarm clock would be good.
- Two different drawing programs you have never used before.
Note that an interface you (or your helper) designed yourself is unsuitable because you will know how it works in great detail.
Once you have chosen an interface, you need to think of one or two common tasks that are carried out with your chosen interface. The tasks should be specific. Some tasks (depending on the interfaces you chose) could be:
- Setting an alarm that will ring at 4:25am tomorrow to catch an early flight (or for a more sophisticated interface, at 7:25am on Monday, Tuesday, Wednesday, and Friday i.e. all weekdays except Thursday, which perhaps you have to get up at 6:30 AM to make it to a really early meeting).
- Sending a text to a friend that says “What are you doing at 3pm today? Want to go for coffee? :-)” (Symbols are good to include in the message, as these can be challenging to find on some interfaces).
- Changing a phone background to a photo you found online.
- Heating some food or water in a microwave for 1 minute, 20 seconds.
- Booking the cheapest flight that will arrive before 11 AM in Auckland from Christchurch, on the next Saturday (stop once you get to the part that asks for payment details!).
- Draw a smiley face with a drawing program. Put your name below the smiley face.
Be sure to read this entire assessment guide carefully (including the sections on writing your report and the hints for success) before beginning this step.
The two projects in the HCI chapter ("Think aloud protocol" and "Cognitive walkthrough") provide detailed procedures of how to do an evaluation using a widely used approach. We recommend choosing one of these (depending on the kind of interface).
Whichever approach you take, tell your helper what the task is, and give them one of your chosen interfaces so that they can carry out the task. While they are carrying out the task, you should be observing and keeping notes on the steps they take, paying particular attention to any points at which they are confused, select an incorrect option (or menu), have to use trial and error (e.g. they know the setting they want is probably in one of three menus, but have to check all three), something they didn't expect happens, wasted time following a dead end, or knew what to do due to useful prompts on the interface (e.g. meaningful icons or naming). Ideally, they will be verbalising their thought process while attempting the task (as in the think-aloud protocol), although keep in mind that some people find this challenging to do.
If you have more than one task for the interface, repeat the above process for each task. Also, if you have a second interface and are aiming for Excellence, repeat the process with the other interface and the same tasks. Remember to keep thorough notes on the entire process. You will need them to write a report that describes and explains what you've observed.
In order to satisfy the requirements of the standard, you should do the following and include all your answers in your report.
Start by writing an introduction to your report. The introduction should specify what interface(s) you have chosen, and what task(s) your helper will be carrying out with them. Briefly explain what your chosen interface(s) are for, and the kinds of steps you would expect to be included in carrying out your task(s). For example, specifying who to send a text to, choosing a suitable flight time, comparing prices of similar items in an e-shop, or setting the time and/ or ring tone for an alarm. A photo or screenshot of your interface(s) and relevant aspects of it are useful to include (but be sure to read the advice near the end of this guide on including images in your report).
You should write your introduction before you do the usability evaluation. By initially thinking about what you would expect to be able to do on the interface(s) for your task(s), you will be in a better position at the end to evaluate whether or not the interface(s) lived up to your expectations.
Now think back to sections 3.3 and/or 3.4 of the book and look over the notes you took during the usability evaluation for your chosen interface(s). Explain the negative characteristics of the interface(s) which caused your helper difficulties. Also explain the positive characteristics of the interface(s) which made it easier for your helper. Be sure to briefly describe the context of each characteristic (e.g. what was the user trying to accomplish at the time? What were they expecting to see happen)? If you have two interfaces, then write up two examples for each interface. If you have one interface, then write up three or four examples for it.
Remember that short and concise paragraphs are far better than long winded rambling. You might have noticed ten different usability issues, but instead of writing about all of them, it is better to pick the three or four that are most likely to come up and are the most serious, and explain them well.
In order to meet the excellence criteria, you need to "discuss how different factors of a user interface contribute to its usability by comparing and contrasting related interfaces". Therefore, you now need to discuss how the usability of the two interfaces compares. What was different between the two interfaces? Which interface did your helper find the easiest to use? Which did they prefer using? Why? If you were designing an interface that could be used for the same task, but was better than both the interfaces you investigated, which ideas would you take from each interface? Which ideas would you stay away from?
Keep in mind that interface design is really challenging to get completely right, and even the best interfaces still have usability issues. In addition, there are often trade-offs (e.g. not all features can be listed on the outermost menu). This is why companies such as Apple, Samsung, and Google put so much money into interface design. The implication of this for you, the one writing a report about usability, is that there are not necessarily any "right" answers. Therefore, you should just focus on explaining and justifying the points you make, and not worrying about whether or not your views are what the marker "wants" to see.
- Be careful to talk about interface usability rather than just features. For example, a cell phone might have a fancy camera able to take very high resolution photos (a feature), but what we’re interested in is how easy it actually is for somebody to take a photo with the camera (a usability factor), especially how easy it is to go from having the phone in your pocket to getting the photo, or from taking the photo to sharing or printing it.
- If your helper struggles to complete the task with the interface, it is likely to be because the interface was not designed well for them. This gives you great material for your project - look for the reasons they had trouble and don’t blame them, as it isn’t their fault.
- Don’t evaluate an interface you designed yourself. As we said in the book, the designer knows the interface really well, and is the worst person to evaluate it!
- The page limit given by NZQA for the length of your report includes your work on algorithms and programming languages. The limit provides enough space to write an excellent report, but to avoid blowing out the page length:
- If you write concisely and clearly, you may be able to cover all the requirements with a page or less of writing (excluding pictures). This is fine, and in fact desirable for the marker as long as you have covered all the requirements.
- Try to keep photos/ screenshots large enough to see, but not so large that they take up needless amounts of space. Be careful about the resolution of them (we see far too many illegible images due to low resolution), and preferably print in colour. If you cannot print in colour, be sure that your images are clear in black and white. Ask your teacher for advice on sizing and positioning of images if you are having trouble.
Within the 3 pages we recommend for Human Computer Interaction, you should include a few images of your interface, and some explanations of the usability factors. For the project outlined above, a possible breakdown is:
- Up to ½ page of text introducing the topic, your chosen interface, and chosen tasks. (Achieved)
- Up to 1 page of text explaining the usability factors identified in the usability evaluation.
- Up to ½ page of text discussing comparing the two interfaces (Excellence)
- Up to ½ to 1 page worth of images (mixed with the above); ensure they are shrunk down in a way that they are still legible but not wasting space.
These are maximums, not targets!
The key to this topic is writing succinctly. Be careful to not ramble. You might not be able to include everything you wanted to; this is okay. Just prioritise and focus on the most interesting 2 or 3 issues for each interface. It is quite possible to use 2 or fewer pages (including images) in this topic, and infact some students have done an amazing job with just one page!
Note that if you go over 3 or 4 pages for Human Computer Interaction, then you may have to use fewer pages for one of the other two topics, which could be problematic.
No other material should be included for Human Computer Interaction. For example, don’t include a list of heuristics explaining each one, or a list of general usability factors. You should only describe factors that directly relate to your chosen user interfaces.