Friday, January 7, 2011

The parishes and Thorndon added to panel data

Two advances today:

1. Finally worked out how to join the dataset that Malcolm has been so patiently preparing to the map of the locations of the parishes. The result is below. Looks a bit as though south-west England is suffering from chicken-pox! We have the data on arable rents, yields, distances to nearest market-town and elevations for these parishes, nearly 800 of them. We have already done the basic statistics and found that there is a very strong relationship between rent, yields, distance and elevations. We also found that the elasticity of rent to what the farmer took home increased markedly as we moved east towards London. I don't know why that should be, but I suspect it might be connected to the amount of 'enclosure' that went on in the area. I'll work on that idea. Next step is to use some free software called Geoda to calculate the 'spatial lag', which is the grouping together of rents. Here's the map and then below some notes on Thorndon.
The 800 (or so!) parishes in south-west England: data from the 1836 Tithe Files
 2. The 'railways' paper: Malcolm calculated the amount of track laid on an annual cumulative basis for Thorndon, the fourth of the estates. Thorndon is in Essex, right over on the east coast, not far north of London. As a result, they had railway track early on. I added Thorndon to the other three estates in the panel data set, and I'm delighted to say that the results remain highly significant. It is clear that landlords were extracting the savings from their tenants----but hey! what else is new? Mi has found me useful information on yields which is part of the estate-specific information I will begin adding to the dataset. Think of it this way: we want to isolate the impact of just one factor---track---so we need to hold steady anything else that might have an effect on rents. This is what we can do with panel-data regression and that's why it is such a powerful tool. So much is done with regression....learn it whenever you get a chance. It will be really useful to you. I'll teach you if you like.

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