what is the meaning of promising attribute and why are we choosing median income as that attribute?
As we have to identify the attributes which are the most correlated i.e. the attributes we think that would highly relate to the price we need to predict (median housing value), in our case median income shows a strong correlation indicative of the price, as we proceed with our analysis, that is what a Promising Attribute means.
are we finding perfect correlation
We have to select the features or attributes we think can show a good positive correlation as suggested by the correlation matrix between every pair or attributes. As we further proceed with the project, we also use pandas and matplotlib to see how does the plot looks like. And Yes, eventually we find the median income, indeed shows a strong positive correlation.