Thursday, April 3, 2014

India Elections Tidbits #2: Margin of victory

Psephology in Indian elections of always interesting. Television commentators and professors from some mathematics istitute discus on television as if what they discovered is a forgone conclusion. I have heard statements like "Now that congress has lost it, what next for them?".
Winning margin for constituencies with less than 5% margin
Following is the list of constituencies with the winning margin.

Constituency NoConstituencyStatePercentage Margin
5ZahirabadAndhra Pradesh1.71%
6MedakAndhra Pradesh0.57%
10ChelvellaAndhra Pradesh1.60%
11MahbubnagarAndhra Pradesh2.43%
12NagarkurnoolAndhra Pradesh4.66%
23KakinadaAndhra Pradesh3.53%
24AmalapuramAndhra Pradesh3.91%
25RajahmundryAndhra Pradesh0.21%
27EluruAndhra Pradesh3.97%
28MachilipatnamAndhra Pradesh1.19%
29VijayawadaAndhra Pradesh1.17%
30GunturAndhra Pradesh3.77%
31NarasaraopetAndhra Pradesh0.15%
37HindupurAndhra Pradesh2.22%
40TirupatiAndhra Pradesh1.82%
42ChittoorAndhra Pradesh1.02%
43Arunachal WestArunachal Pradesh0.46%
45KarimganjAssam1.16%
50BarpetaAssam3.38%
51GauhatiAssam1.07%
53TezpurAssam3.58%
54NowgongAssam4.54%
57DibrugarhAssam4.68%
58LakhimpurAssam4.90%
69KatiharBihar1.88%
74VaishaliBihar2.70%
79HajipurBihar4.45%
89PataliputraBihar3.75%
100South GoaGoa4.60%
102BanaskanthaGujarat0.84%
105SabarkanthaGujarat2.39%
118PanchmahalGujarat0.19%
126ValsadGujarat0.51%
129SirsaHaryana2.41%
147ChikkodiKarnataka4.42%
149BagalkotKarnataka2.47%
157DharwadKarnataka3.70%
163Dakshina KannadaKarnataka3.22%
167MysoreKarnataka1.70%
170Bangalore NorthKarnataka3.62%
172Bangalore SouthKarnataka2.90%
180MalappuramKerala0.00%
183AlathurKerala2.53%
184ThrissurKerala3.20%
186ErnakulamKerala1.58%
196BhindMadhya Pradesh4.38%
203SatnaMadhya Pradesh0.44%
209BalaghatMadhya Pradesh3.82%
216UjjainMadhya Pradesh4.48%
218RatlamMadhya Pradesh4.65%
222KhandwaMadhya Pradesh4.28%
224NandurbarMaharashtra3.97%
228BuldhanaMaharashtra3.29%
253Mumbai South CentralMaharashtra4.93%
264LaturMaharashtra1.51%
276MizoramMizoram0.00%
286DhenkanalOrissa2.17%
287BolangirOrissa4.82%
289NabarangpurOrissa0.00%
295BhubaneswarOrissa1.46%
303HoshiarpurPunjab2.93%
308FerozpurPunjab2.20%
339Chennai NorthTamil Nadu2.90%
340Chennai SouthTamil Nadu4.52%
342SriperumbudurTamil Nadu2.23%
344ArakkonamTamil Nadu1.41%
350ViluppuramTamil Nadu0.35%
360KarurTamil Nadu3.12%
362PerambalurTamil Nadu0.95%
368SivagangaTamil Nadu0.43%
370TheniTamil Nadu0.41%
380KairanaUttar Pradesh3.10%
381MuzaffarnagarUttar Pradesh1.60%
401BadaunUttar Pradesh1.96%
408SitapurUttar Pradesh2.79%
423JalaunUttar Pradesh0.91%
433Ambedkar NagarUttar Pradesh1.87%
437GondaUttar Pradesh1.37%
449SalempurUttar Pradesh4.64%
480JadavpurWest Bengal4.54%
483HowrahWest Bengal3.75%
484UluberiaWest Bengal4.64%
509MahasamundChattisgarh4.11%
523LohardagaJharkhand1.45%
In summary, based on last election, there are 149 constituencies which were won with less than 5% margin.

  • Less than 1% margin  -- 16 seats
  • Between 1% and 2% margin -- 19 seats
  • Between 2 % and 3% margin -- 30 seats
  • Between 3% and 4% margin -- 36 seats
  • Between 4% and 5% margin -- 48 seats
With such a large number of seats won with so low margin, how can these television commentators be so confident of seats won. Also how can they take the margin of error in votes polled and extrapolate that to number of seats.