How do I prevent certain combinations from appearing using the "Married Pair" feature?
This lesson shows how to remove certain "impossible to test for" combinations using the "Married Pair" feature under the "Constraints" tab (which is closely related to Hexawise's Invalid Pair feature).
Imagine that you have these inputs...
You will have the following issue when you click on the "Test Cases" button:
To solve this problem, you first need to add "Not Applicable" as inputs
This is because something will need to appear in test cases that include the value "Do Not Add a Hotel".
We will want "Not Applicable" to appear for both "Hotel Chain Preference" and "Type of Room" in every scenario that includes the value "Do Not Add a Hotel".
Next, you'll want to make sure that "Do Not Add a Hotel" only gets paired with the "Not Applicable" Values.
You have two options under the "Constraints" tab. One is quick, the other is slow. Let's see the slow option, first
Namely, it's adding a lot of "Invalid Pairs" as described in more detail here.
This is the quick option... Married Pairs!
Confirm how you'd like to have the married pair operate:
Most of the time when you have "Not Applicable" as an option, you will use "Bi-directional," as in this case. Here, we want "Do Not Add a Hotel" to be paired with Type of Room as "Not Applicable" AND we want to have Type of Room of "Not Applicable" to be paired up with "Do Not Add a Hotel" so we mark this one as a Bi-directional Married Pair. For more information on what each type of Married Pair is, go here.
Boom! Pow! Shazam! Problem solved!
So what really just happened there?
When you add a Married Pair, Hexawise will constrain the first value chosen against all the other values in the parameter of the second value chosen. In the example above, creating a married pair of 'Do Not Add Hotel' and 'Hotel Chain Preference' = 'Not Applicable' means you are really invalidating these options:
- 'Do Not Add a Hotel' with 'Hotel Chain Preference = Marriott' (this combination will never appear).
- 'Do Not Add a Hotel' with 'Hotel Chain Preference = Hilton' (this combination will never appear).
- 'Do Not Add a Hotel' with 'Hotel Chain Preference = Motel One' (this combination will never appear).
- 'Do Not Add a Hotel' with 'Hotel Chain Preference = Vivanta by Taj' (this combination will never appear).
And because we created a BI-DIRECTIONAL Married Pair, we are also invalidating these potential combinations also:
- 'Do Add a Hotel' with 'Hotel Chain Preference = Not Applicable' (this combination will never appear).
As you use the Married Pair feature, keep the following tips in mind:
- You can use Hexawise's Invalid Pair feature to accomplish anything that the Married Pair feature can do.
- The Invalid Pair feature is frequently less confusing to use for new users than the Married Pairs feature. Don't hesitate to use the Invalid feature instead of the Married Pair feature.
- If you have more than 10 or so Married Pairs or Invalid Pairs in a plan, you might find that it is easier and faster to document your paired values in Excel. If so, we would recommend (a) adding multiple paired values in Hexawise before you export into Excel, and (b) ensuring that you use the exact spelling of Values (e.g., 'cutting and pasting' is usually safer than typing)
- Watch out for "Not Applicable" values. Do you need to add them to your plan? Do you need to invalidate the combination of "Not Applicable" with other selections? (In the example above, we did not want "Do Add a Hotel" to appear together with 'Hotel Chain Preference = Not Applicable')
- Especially watch out for situations where you have MULTIPLE related "Not Applicable" values in a plan. Would it make sense to create a "Married Pair" between, say, 'Hotel Chain Preference = Not Applicable' and 'Type of Room' = Not Applicable'? In the example above, it WOULD make sense to include that Married Pair. Every time 'Hotel Chain Preference' = 'Not Applicable' we would want 'Type of Room' to also be 'Not Applicable' also. Similarly, every time 'Type of Room' = Not Applicable, we would want 'Hotel Chain Preference' to also be 'Not Applicable'. This is an example of a type of constraint that the human brain would handle effortlessly without even consciously applying logical rules.