Stata ADO file for calculating the Issue Yield index (De Sio and Weber 2014, 2020) on a survey dataset. For a particular political party, the index summarizes the electoral risk/opportunity combination associated with a particular issue goal (risks of internal division vs opportunity for electoral expansion among non-supporters). Besides text output, the program also returns a full set of scalars to ease automation.
issueyield <issue_position_variable>, partyexp(<party_expression>) [wtexp(<weight_expression>)] [credvar(<credibility_variable>)]
where variables are:
issue_position_variable : a dichotomous variable indicating whether the respondent supports the issue goal;
party_expression : an expression identifying party supporters;
credibility_variable : a dichotomous variable indicating whether the respondent deems the party credible on the issue goal;
weight_expression : a Stata weight expression to apply weights.
Using ANES Time Series 2020 data (retrieved from https://electionstudies.org/anes_timeseries_2020_stata_20220210/), calculates issue yield for support for death penalty, separately for (pre-electoral) supporters of the Democratic and Republican presidential candidates.
include "issueyield.ado"
use "anes_timeseries_2020_stata_20220210.dta" , clear
recode V201075x (10 20 30 = 1 "Dem") (11 21 31 = 2 "Rep") (12 22 32 = 3 "Other"), gen(pres_voteintpref)
recode V201345x (1 2 = 1 "Favor death penalty") (3 4 = 0 "Oppose death penalty") (-2 = .), gen(issue01_favordeathpenalty)
issueyield issue01_favordeathpenalty, partyexp("pres_voteintpref==1")
issueyield issue01_favordeathpenalty, partyexp("pres_voteintpref==2")
*** Issue Yield index calculation ***
Issue variable: issue01_favordeathpenalty (RECODE of V201345x (PRE: SUMMARY: R favor/oppose death penalty))
Party expression: pres_voteintpref==1
Party size (p): 0.50
Issue goal general support (i): 0.61
Joint party-goal support (f): 0.21
* Issue yield: -0.14
*** Issue Yield index calculation ***
Issue variable: issue01_favordeathpenalty (RECODE of V201345x (PRE: SUMMARY: R favor/oppose death penalty))
Party expression: pres_voteintpref==2
Party size (p): 0.39
Issue goal general support (i): 0.61
Joint party-goal support (f): 0.32
* Issue yield: 0.70
Same as above (for Republicans), but weighting observations by V200010b.
issueyield issue01_favordeathpenalty, partyexp("pres_voteintpref==2") wtexp("[aw=V200010b]")
*** Issue Yield index calculation ***
Issue variable: issue01_favordeathpenalty (RECODE of V201345x (PRE: SUMMARY: R favor/oppose death penalty))
Party expression: pres_voteintpref==2
Using weights: [aw=V200010b]
Party size (p): 0.36
Issue goal general support (i): 0.63
Joint party-goal support (f): 0.29
* Issue yield: 0.71
Using ICCP 2017-18 v2 data, retrieved from here (also available as GESIS study ZA7499), calculates issue yield for introduction of a flat tax, separately for (pre-electoral) supporters of Italy's Lega and PD (Partito Democratico).
use "ICCP_voter_survey_it17_lbl", clear
rename goal_it_p5 issue01_flattax
issueyield issue01_flattax, partyexp(`"voteint_party=="it_lega""')
issueyield issue01_flattax, partyexp(`"voteint_party=="it_pd""')
*** Issue Yield index calculation ***
Issue variable: issue01_flattax (Maintain actual tax progressivity or introduce flat tax)
Party expression: voteint_party=="it_lega"
Party size (p): 0.12
Issue goal general support (i): 0.24
Joint party-goal support (f): 0.06
* Issue yield: 0.40
*** Issue Yield index calculation ***
Issue variable: issue01_flattax (Maintain actual tax progressivity or introduce flat tax)
Party expression: voteint_party=="it_pd"
Party size (p): 0.15
Issue goal general support (i): 0.24
Joint party-goal support (f): 0.02
* Issue yield: -0.03
Same as Example 3, but also calculating credibility-weighted Issue Yield, which takes into account an explicit (dichotomous) measure of party credibility to achieve the goal.
issueyield issue01_flattax, partyexp(`"voteint_party=="it_lega""') credvar(cred_it_p5_lega)
issueyield issue01_flattax, partyexp(`"voteint_party=="it_pd""') credvar(cred_it_p5_pd)
*** Issue Yield index calculation ***
Issue variable: issue01_flattax (Maintain actual tax progressivity or introduce flat tax)
Party expression: voteint_party=="it_lega"
Party credibility variable: cred_it_p5_lega
Party size (p): 0.12
Issue goal general support (i): 0.24
Joint party-goal support (f): 0.06
* Issue yield: 0.40
Party credibility (cred): 0.32
Party credibility in *f* set (intcred):0.72
* Credibility-weighted issue yield: 0.23
*** Issue Yield index calculation ***
Issue variable: issue01_flattax (Maintain actual tax progressivity or introduce flat tax)
Party expression: voteint_party=="it_pd"
Party credibility variable: cred_it_p5_pd
Party size (p): 0.15
Issue goal general support (i): 0.24
Joint party-goal support (f): 0.02
* Issue yield: -0.03
Party credibility (cred): 0.09
Party credibility in *f* set (intcred):0.39
* Credibility-weighted issue yield: -0.07
Same as in Example 4, but weighting observations by wdempol_trim.
issueyield issue01_flattax, partyexp(`"voteint_party=="it_lega""') credvar(cred_it_p5_lega) wtexp("[aw=wdempol_trim]")
*** Issue Yield index calculation ***
Issue variable: issue01_flattax (Maintain actual tax progressivity or introduce flat tax)
Party expression: voteint_party=="it_lega"
Using weights: [aw=wdempol_trim]
Party credibility variable: cred_it_p5_lega
Party size (p): 0.12
Issue goal general support (i): 0.26
Joint party-goal support (f): 0.06
* Issue yield: 0.43
Party credibility (cred): 0.29
Party credibility in *f* set (intcred):0.68
* Credibility-weighted issue yield: 0.23