Unfortunately you cannot have the tooltip on blank space because they only appear if you hover over data points. What is exactly the intended outcome of a hover over where there is no data?
You could possible create a workaround where you have data point in a separate worksheet, make them invisible (colour them white) and make the worksheet a floating element on top of your scatter.
Let me know if this helps.
Thanks for your time. The my intention is to show like a help information about that quandrant means.
As you said about invisible worksheet, if the data element being under this invisible worksheet, invisible worksheet will be over the scatter element?
Is Tooltip ONE a static tooltip with some help instructions? You can right click on the chart and select Annotation > Area and it will create a sticky note that stays in place. It would not be a tooltip.
The other option would be to create a sheet, select mark type of Shape, choose a shape (I used a custom question mark) then put a tooltip in that sheet. Drop it into your dashboard as floating and you have a tooltip help section! I would suggest you make it visible so the user knows they can hover for help. If it is white and hidden, they may or may not run into it.
Sheet with Help Icon and Tooltip...
Indeed if you want to have information on how to use the scatter, such as "hover over points for more info", you can use the technique described by Aaron. I agree that an invisible hover over is not user-friendly. It will be hard to find.
There are two other techniques which you can use to draw attention to the interpretation the four different quadrants. These will bring them out the story more visually.
1. Encoding the data points by colour:
2. Using a background image:
Let me know which one you decide to go for.
Hello Sasha, the best option for us is using second option from AARON indication.