Before we dive in to the specific methods for valuating your design,

it's important that we understand the two key categories research,

qualitative and quantitative.

Qualitative research methods are common to both the generative and

tactical phases of research.

All qualitative research shares the intent,

to understand the range of behavior for your desired audience,

as well as the motivations and perceptions that lead them there.

And what the heck does that mean?

In the first phase, generative, if you're designing a product for

surgeons in the operating room, you need to note everything that happens there.

Why it happens and what the surgeons are thinking in the process?

In the second phase, tactical,

you're creating a prototype to keep surgeons more alert during a procedure.

You need to see how they use this prototype to keep awake, why the do this,

and what they think along the way?

And finally, in the third phase, evaluative.

If you've launched a product,

keep track of how people are using it in the real world.

If you observe something you don't understand,

dig deeper to discover why users are doing things this way and, again,

what they're thinking along the way.

Something else that all qualitative research has in common is talking and

observing people directly.

It cannot be automated, and often means talking to just a few people for

each study, usually five to eight is enough.

Now on to quantitative research, which is, a structured method

of data gathering and analysis involving mathematical rigor.

Let's take into what that means in practical terms.

Unlike qualitative data,

which can be gathered from in-depth discussions with a small number of people,

quantitative data involves hundreds or thousands of people.

Use quantitative methods when you want to understand how people use your product in

a statistically meaningful way that could be generalized to the entire population.

Use qualitative methods when you want an in-depth understanding of

the underlining why behind their behavior.

Luckily, you don't need to always choose between qualitative and

quantitative methods.

In fact, it's often best to combine these methods.

You can conduct a handful of interviews qualitatively in order to inform

a survey that will be sent another few thousand people quantitatively.

Or you can observe a pattern amongst the thousands of people using your service,

quantitatively.

And then select a few of them to interview in order to understand why this happens,

qualitatively.

Now, let's dive into usability studies,

a common qualitative method for tactical research.