Ossoff2028's Index of House District Partisanship

[This is Eharding, guys]

Since nobody answered my question here:
https://uselectionatlas.org/FORUM/index.php?topic=268004.0
with any true rigor, I've decided to solve this problem on my own.

2016 House (two-party)
https://fusiontables.google.com/embedviz?q=select+col5%3E%3E1+from+1Dg51R3pGS5r0HrSuoHSUXR_IxZIfcClrwl7gsLXk&viz=MAP&h=false&lat=37.05628800013914&lng=-93.02554824999993&t=1&z=4&l=col5%3E%3E1&y=2&tmplt=2&hml=KML
2016 presidential vote by congressional district (two-party)
https://fusiontables.google.com/embedviz?q=select+col18+from+1_NolOUGbBkWbAl5TMMZrpba-OazN7DBf7dvSTUie&viz=MAP&h=false&lat=37.05628800013914&lng=-93.02554824999993&t=1&z=4&l=col18&y=2&tmplt=2&hml=GEOCODABLE
2012 presidential vote by congressional district (two-party)
https://fusiontables.google.com/embedviz?q=select+col18+from+1T2Q2YVeHXfCqiV466yZqciXyOF48DMGD3cZ2hxac&viz=MAP&h=false&lat=37.05628800013914&lng=-93.02554824999993&t=1&z=4&l=col18&y=2&tmplt=2&hml=GEOCODABLE
Two-Party Swing between 2012 and 2016 presidential vote:
https://fusiontables.google.com/embedviz?q=select+col18+from+18XmouMM-7G0SD_6dykEyD9gfgNnGmoiPpfbIdMYV&viz=MAP&h=false&lat=37.05628800013914&lng=-93.02554824999993&t=1&z=4&l=col18&y=2&tmplt=2&hml=GEOCODABLE
Two-party House Dem vote performance over two-party HRC vote in 2016
https://fusiontables.google.com/embedviz?q=select+col18+from+1IdPacdK9LIHkbXRyC2l4WdZx5E6RXCqDmwS70jSK&viz=MAP&h=false&lat=37.05628800013914&lng=-93.02554824999993&t=1&z=4&l=col18&y=2&tmplt=2&hml=GEOCODABLE
Ossoff2028's composite index of House district partisanship (will be updated depending on retirements, etc.)
https://againstjebelallawz.wordpress.com/2017/08/04/house-district-partisanship-map-link-will-be-updated-as-news-arrive/
The index of House district partisanship is labeled as the "composite".

The "composite" is calculated as thus.

If the seats were uncontested, 2/3 of the weight is on the 2012 presidential vote, the rest on the 2016 presidential vote; i.e., uncontested seats are treated as if they were open seats. I have also calculated the open seats listed as open in 2018 in Wikipedia in this fashion. The weighing is based on David Shor's data. https://gist.github.com/davidshor/5ea3e6c4e80cdc87243253e47c47bc41

If they are seats contested in 2016 with an incumbent, 50% of the weight is on the 2016 House vote, 30% is on the 2016 presidential vote, and 20% is on the 2012 presidential vote. This weighing is roughly based on comparing the 2014 and 2016 House elections and taking note of the increased importance of the 2012 presidential vote in the 2017 specials relative to 2016's House races.

All data is from the Daily Kos.

The rank is the ranking of the districts by partisanship by the composite index.

You can get the source data by clicking "source" in the map legend.

The districts held by the 2017 special election GOP winners are calculated as though their House members in 2016 were still serving today, without regard to the 2017 special election results (as different from the 2016 results as apples are from oranges) as they really cannot be viewed as open seats in 2018.

No attempt is made to account for asymmetric deterioration of incumbent bonuses in bad midterms for a president's party, as happened in 2006 and 2010 (thus Collin Peterson and other Trump district Dems are probably underrated with this composite).

[At-Large Senator LouisvilleThunder]

Great work

[BuckeyeNut]

Seems very similar to Cook PVI, which you were linked to in the first thread.

[President Punxsutawney Phil]

Great work

[This is Eharding, guys]

Seems very similar to Cook PVI, which you were linked to in the first thread.

Cook PVI is only at presidential level. My index is fully half 2016 House margin for seats with incumbents. Big difference. Thus, districts that elect people like Collin Peterson and Carlos Curbelo are, correctly in my humble opinion, rated as less extremely GOP and Dem, respectively, by my index than by Cook PVI.

[This is Eharding, guys]

Updated to account for Steve Pearce's and Jason Chaffetz's retirements (which I missed last time). Also added presidential two-party swing map.

[Since I'm the mad scientist proclaimed by myself]

Taking into account house 2016 vote is problematic, as factors such as variations in the quality of the opposing candidate can wildly swing the seat(EG AZ-02 swinging 10 points R in 2016 because Heinz was a terrible candidate with effectively no campaign.) Seats won in waves often swing quite wildly from the house vote in the previous year.

[This is Eharding, guys]

Taking into account house 2016 vote is problematic, as factors such as variations in the quality of the opposing candidate can wildly swing the seat(EG AZ-02 swinging 10 points R in 2016 because Heinz was a terrible candidate with effectively no campaign.) Seats won in waves often swing quite wildly from the house vote in the previous year.

Of course it is problematic due to the factors you mention. But I can't see a better solution than that, since Pennsylvania, Minnesota, and New York all have at least one Trump district D-held seat and one HRC district R-held seat. I, for one, don't think Dave Reichert's seat in WA-08 will be more likely to go Democrat in 2018 than AZ-01.

Also, added two-party House Dem vote performance over two-party HRC vote in 2016, which I missed last time.

[Technocracy Timmy]

This is amazing!

[This is Eharding, guys]

Updated Composite index to include John Duncan and John Delaney's retirements. Not like it changes much.

[Since I'm the mad scientist proclaimed by myself]

Taking into account house 2016 vote is problematic, as factors such as variations in the quality of the opposing candidate can wildly swing the seat(EG AZ-02 swinging 10 points R in 2016 because Heinz was a terrible candidate with effectively no campaign.) Seats won in waves often swing quite wildly from the house vote in the previous year.

Of course it is problematic due to the factors you mention. But I can't see a better solution than that, since Pennsylvania, Minnesota, and New York all have at least one Trump district D-held seat and one HRC district R-held seat. I, for one, don't think Dave Reichert's seat in WA-08 will be more likely to go Democrat in 2018 than AZ-01.

Also, added two-party House Dem vote performance over two-party HRC vote in 2016, which I missed last time.

You have to accept that a map based on data isn't going to be perfect, and a map that underestimates a few strong incumbents is better then a map that overestimates a lot of mediocre incumbents who had bad challengers.

[This is Eharding, guys]

Taking into account house 2016 vote is problematic, as factors such as variations in the quality of the opposing candidate can wildly swing the seat(EG AZ-02 swinging 10 points R in 2016 because Heinz was a terrible candidate with effectively no campaign.) Seats won in waves often swing quite wildly from the house vote in the previous year.

Of course it is problematic due to the factors you mention. But I can't see a better solution than that, since Pennsylvania, Minnesota, and New York all have at least one Trump district D-held seat and one HRC district R-held seat. I, for one, don't think Dave Reichert's seat in WA-08 will be more likely to go Democrat in 2018 than AZ-01.

Also, added two-party House Dem vote performance over two-party HRC vote in 2016, which I missed last time.

You have to accept that a map based on data isn't going to be perfect, and a map that underestimates a few strong incumbents is better then a map that overestimates a lot of mediocre incumbents who had bad challengers.

2014 famously had no correlation between swing from 2012 and the 2012 presidential vote in House races that weren't open.
https://www.dailykos.com/stories/2015/3/29/1368912/-Daily-Kos-Elections-presents-our-fully-interactive-visualizations-of-the-2014-federal-elections
Obviously, no prediction is going to be perfect, but I think giving half of the weight to the 2016 House vote is perfectly reasonable given past results. The correlation between 2012 presidential and 2014 House vote was .89, that between 2012 House vote and 2014 House vote was .93.

[🐒Gods of Prosperity🔱🐲💸]

Cool maps.

I never realized til now that Democrats only contested 1 seat in AR with Hillary running for president, which is weird to think about.

[This is Eharding, guys]

Now that I've been found out as Eharding, the link will now be to a blogpost which will be edited to show the correct link every time the FusionTable is updated. Allies, please continue bumping this thread until the 2018 elections.

[heatcharger]

Mods, please delete this thread, thanks.

[This is Eharding, guys]

Mods, please delete this thread, thanks.

Why? My index is certainly more useful than whatever garbage the race ratings websites put out.

[Virginiá]

I'm not going to delete the thread, as he did contribute here, but he won't be updating this any longer himself.

It would have been nice if eharding could have acted more like ossoff2028 rather than his real self the first time around.