We've got a lot of demographic variables, it's not just college educated, it's also measurements of how many elderly people are in the area, ethnicity which is a measurement of how many blacks and Hispanics, the log of the median income, are the family sizes large? Working women, so in this case, let me just read this off. It means that on the average in Chicago, 36% of households have working women. You know the standard deviation is around .05, so you know it's going something between 20 and 50,60 percent. Household value over 150 thousand, and the point is that some of these standard deviations are low - others are quite large. So if you think about the dispersion across these stores, there's actual xxx dispersion in the housing market. It goes back to the question, can you really do this at the store level? Well, obviously, at the individual household level there's a lot of differences. But the point is, that people tend to cluster with people that are similar to themselves. And there are good reasons for that, and I think that's just trying to illustrate this fact.
And now I talk about the last four demographic independent variables that we have. Our measurements of the distances between the stores and relative volume of the competitor's store to my overall sales. So the distance is measured in miles, on average the distance to the nearest warehouse competitor, like a Club store or a large warehouse store like something that would be more similar to a Wal-mart, would be like 6 miles. Whereas on average for the - the average distance to my nearest competitor or a actually a weighted average of my five competitors is going to be about 2 miles. Now the point is that some stores are right next to each other, other stores are far away, so again you are just trying to capture this notion of what do I know about the market.
I just want to pause here, because this sort of completes the first segment that I wanted to go through and explain what this data looked like to try to give you some flavor of what the problem is and now we start thinking about, well, how are we going to go out and model demand. So our main question is about the data or about the problem itself.
For more description of competitive/demographic characteristics click here