Comparison of pollsters

Visualize and analyze the accuracy of polls/surveys by comparing polling agencies data.

Sentil Pillai
Student @ Cousera

Purpose

  • Do all the polls move in the same direction at the same time?

  • Is the margin of error of 3 percentage points accurate?

  • Is dramatic new events reflected in the poll data? This may suggest that the poll data is measuring something real.

Data source

For analysis the data (BushApproval) from R library “UsingR” is used.
http://cran.r-project.org/web/packages/UsingR/UsingR.pdf

The original source of the data used by the library is from.
http://www.pollingreport.com/BushJob.htm

Data

library(UsingR)
summary(BushApproval)

##      date              approval          who     
##  Length:323         Min.   :45.0   fox     : 64  
##  Class :character   1st Qu.:56.0   gallup  :119  
##  Mode  :character   Median :63.0   newsweek: 55  
##                     Mean   :64.9   time.cnn: 30  
##                     3rd Qu.:73.0   upenn   : 10  
##                     Max.   :90.0   zogby   : 45
  • Most polls were of size approximately 1,000; Consisting of registered voters or likely voters.
  • Date: The date poll was begun (some take a few days)
  • Approval: A numeric number between 0 and 100
  • Who/Pollster: A factor with six levels Fox, Gallup, Newsweek, Time.CNN, UPenn, Zogby

Trivia quiz

The approval ratings of President George W. Bush was

A ) 81 reported by Fox on 2001-09-19
B ) 86 reported by Newsweek on 2001-09-20
C ) 90 reported by Gallup on 2001-09-21

Which of the above approval rating by several pollster agencies statement is true ?

  1. Only A

  2. Only B

  3. Only C

  4. None of the above

  5. All the above

The highest approval-rating during the first term of his precedency was post 9-11 event.

All the above, the polling data shows 9 point/percent change over three day period.

Interaction with App

Choose one or more of the pollsters by checking the box.

Choose a time frame during the first term precedency, by selecting start and end dates.

Three tabs on the right reactively re-display

  • Data table tab: Dataset is displayed in table format, columns are sortable and searchable.

  • Data summary tab: Dataset is summarized using the R summary function.

  • Plot tab: Plots the approval rating by pollsters over time.

Try it

http://sentilpillai.shinyapps.io/bush/