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The Correlates of State Policy Project aims to compile, disseminate, and encourage the use of data relevant to U.S. state policy research, tracking policy differences across and change over time in the 50 states. We have gathered more than nine-hundred variables from various sources and assembled them into one large, useful dataset. We hope this Project will become a “one-stop shop” for academics, policy analysts, students, and researchers looking for variables germane to the study of state policies and politics.  

In keeping with the mission of IPPSR, this Project documents, updates, and distributes various datasets germane to research on pressing public policy issues. IPPSR is committed to research transparency, replication, and data reliability. These cross-state and cross-time datasets are free and publicly available for academics, policy analysts, students, policymakers, and the research community. We welcome notification of any errors, comments, and contributions of additional datasets. 

Read more in our new paper announcing the dataset.

About the Datasets:

The Correlates of State Policy Project includes more than nine-hundred variables, with observations across the U.S. 50 states and time (1900 – 2016). These variables represent policy outputs or political, social, or economic factors that may influence policy differences across the states. The codebook includes the variable name, a short description of the variable, the variable time frame, a longer description of the variable, and the variable source(s) and notes.

This aggregated data set is only possible because many scholars and students have spent tireless hours creating, collecting, cleaning, and making data publicly available. Thus if you use the dataset, please cite the original data sources. For example, if you use the dataset to examine the relationship between the Policy Innovativeness Score created by Boehmke & Skinner (2012) and the Policy Liberalism Score created by Caughey & Warshaw (2015), you should include the following three citations:  
     - Boehmke, Frederick J., and Paul Skinner. 2012. “State Policy Innovativeness Revisited.” State Politics and Policy Quarterly 12(3):303-29.
     - Caughey, Devin, and Christopher Warshaw. 2015. “The Dynamics of State Policy Liberalism, 1936–2014.” American Journal of Political Science 60 (4): 899–913. 
     - Jordan, Marty P. and Matt Grossmann. 2016. The Correlates of State Policy Project v.1.10. East Lansing, MI: Institute for Public Policy and Social Research (IPPSR).

Data Downloads (Large Files) Version 1.10:

Data via Google Charts

Documentation:

Related Projects

Updates

Version 1.10

Corrected an error with hou_chamber variable

Version 1.9

Variables Added

Labor Force and Social Welfare Demographics

  • employed Employed Population (Total Number)
  • unemployed Unemployed Population (Total Number)
  • marginallyfoodinsecure Marginally Food Insecure
  • foodinsecure Food Insecure
  • verylowfoodsecure Very Low Food Insecure
  • lowincchildren_number Number of Low Income Uninsured Children
  • afdccases_childonly AFDC/TANF Child-Only Caseloads
  • wicparticipation WIC Participation
  • nslp_free NSLP Free Participation
  • nslp_reduced NSLP Reduced Participation
  • nslp_total Total NSLP Participation
  • sbp_free SBP Free Participation
  • sbp_reduced SBP Reduced Participation
  • sbp_total Total SBP Participation
  • workerscompensation Workers’ Compensation
  • stateeitcrate State EITC Rate

SSI Recipients

  • ssistate Maximum SSI State Benefits
  • ssitotal Total SSI Benefits
  • ssirecipients_total Total Number of SSI Recipients
  • ssirecipients_aged Number of Aged SSI Recipients
  • ssirecipients_blind Number of Blind SSI Recipients
  • ssirecipients_disabled Number of Disabled SSI Recipients

Version 1.8

Variables Added

Tax Rates

  • wine_tax Wine Tax Rate
  • wine_tax_rank Ranking of Wine Tax Rate
  • spirit_tax Spirit Tax Rate
  • spirit_tax_rank Ranking of Spirit Tax Rate
  • beer_tax Beer Tax Rate
  • beer_tax_rank Ranking of Beer Tax Rate

Social Capital

  • soc_capital Social Capital
  • soc_capital_ma Moving Average Weighted Social Capital

Policy Liberalism

  • st_ec Mean Economic Liberalism- All Survey Respondents
  • st_soc Mean Social Liberalism- All Survey Respondents
  • avgec_low Mean Economic Liberalism- Low Income Respondents
  • avgsoc_low Mean Social Liberalism- Low Income Respondents
  • avgec_mid Mean Economic Liberalism- Mid Income Respondents
  • avgsoc_mid Mean Social Liberalism- Mid Income Respondents
  • avgec_high Mean Economic Liberalism- High Income Respondents
  • avsoc_high Mean Social Liberalism- High Income Respondents
  • vst_ec Mean Economic Liberalism- All Voters
  • vst_soc Mean Social Liberalism- All Voters
  • vavgec_low Mean Economic Liberalism- Low Income Voters
  • vavgsoc_low Mean Social Liberalism- Low Income Voters
  • vavgec_mid Mean Economic Liberalism- Mid Income Voters
  • vavgsoc_mid Mean Social Liberalism- Mid Income Voters
  • vavgec_high Mean Economic Liberalism- High Income Voters
  • vavgsoc_high Mean Social Liberalism- High Income Voters

Version 1.7

Fixed: We fixed a sort error that affected variables from Carl Klarner’s "Governors Dataset.” This error existed in versions 1.0–1.5. Variables from that dataset include:

prez_election_year, weird5, weird5_b, biennium, biennium_b, biennium_first_year, biennium_second_year, govname1, govname1_sour, govname1_date, govname2, govname2_sour, govname2_date, govname2_notes, gub_election, gub_election_regime, gov_midyear_change_date, gov_midyear_change_month, gov_midyear_change_day, gov_midyear_change_ordinal_day, gov_midyear_change_a, budget_pass2011_04_20, when_leg_met2011_04_13, gov_midyear_change_b, gov_midyear_change_b_note, new_gov_b, past_gov, past_gov_note, gov_midyear_change_c, gov_midyear_change_c_note, new_gov_c,d, fracleg_old_variable, fracleg_old_variable_note, years_served, budgets_overseen, years_served_budgets_overseen_notes, term_length, years_left_in_term, limit_exists, limit_type, term_limit_length_uncertainty, years_left_before_limit, years_left_before_limit_note, years_left_before_limit_uncertai, lame_duck_last_term, lame_duck_last_year, lame_duck_last_2nd_to_last_year, lame_duck_notes, femgov, femgov_notes, stateleg, stateleg_sour, congmem, congmem_sour, stateleg_congmem_notes, legexper, party_midyear_change, party_midyear_change_direction, govparty_a, party_midbiennium_change, party_midbiennium_change_direction, govparty_b, govparty_b_2, state_midterm_penalty, govparty_c, gov_non_maj_pty, gub_party_change, gov_pty_change_since_last_budget, gov_pty_change_since_lst_budget2, years_since_other_party, open_bcs_term_limit

Variables Added :

Campaign Finance

  • overall_fin_reg Overall Campaign Finance Stringency
  • disclosure_fin_reg Campaign Finance Disclosure Stringency
  • public_fin_reg Public Campaign Finance Stringency
  • indlimit Limit on Individual Campaign Contributions
  • famlimit Limit on Family Campaign Contributions
  • candlimit Limit on Candidate Self-Contributions
  • corplimits Limit on Corporate Campaign Contributions

Demographics

  • nonwhite Nonwhite Population

Interest Groups

  • union_density Union Density

Welfare Spending

  • welfare_spending_percap Welfare Spending
  • cash_assist_percap Cash Assistance Spending
  • unemploy_comp_percap Unemployment Compensation Spending

Economic Freedom

  • efna_index EFNA index of the State Economic Freedom

Legislative Professionalism

  • sess_length Session Length
  • leg_realsalary Legislator Salary
  • leg_expend Legislator Expenditures
  • bowen_legprof_firstdim First Dimension Professionalism Score
  • bowen_legprof_seconddim Second Dimension Professionalism Score

Version 1.6

Income Inequality

  • gini_coef State income inequality measured by Gini Coefficient
  • atkin_index State income inequality measured by Atkinson Index
  • theil_index State income inequality measured by Theil Index

Government Integrity

  • integrity State Government Integrity

Version 1.5

  • Variables Added
    Measures of State Corruption
    corruption_convict Convictions relating to corruption (“criminal abuses of pubic trust by government officials”)
    Interest Groups
    christright_inf Index measuring the Influence of Christian Right Interest Groups
    Health Care
    med_enroll_aged Number of Medicaid Enrollees in the Aged Enrollment Group
    med_enroll_disab Number of Medicaid Enrollees in the Disability Enrollment Group
    med_enroll_adult Number of Medicaid Enrollees in the Adult Enrollment Group
    med_enroll_child Number of Medicaid Enrollees in the Children Enrollment Group
    med_enroll_total Total Number of Medicaid Enrollees
    med_spend_aged Total Medicaid Spending on Enrollees in the Aged Enrollment Group
    med_spend_disab Total Medicaid Spending on Enrollees in the Disability Enrollment Group
    med_spend_adult Total Medicaid Spending on Enrollees in the Adult Enrollment Group
    med_spend_child Total Medicaid Spending on Enrollees in the Children Enrollment Group
    med_spend_total Total Medicaid Spending
    Political Knowledge
    know_gov Percent of population who can correctly name their Governor.
    know_govparty Percent of population who can correctly name the party of their Governor.
    partisan_knowledge_scale Number of items correct on Cooperative Congressional Election Study’s partisan knowledge scale
    Income Inequality
    incshare_top10 Share of total income earned by the top 10% of earners
    incshare_top5 Share of total income earned by the top 5% of earners
    incshare_top1 Share of total income earned by the top 1% of earners
    incshare_top05 Share of total income earned by the top 0.5% of earners
    incshare_top01 Share of total income earned by the top 0.1% of earners
    incshare_top001Share of total income earned by the top 0.01% of earners
    Government Measures
    speaker_power Index of State Speaker of the House power. Year is coded for the beginning of the Legislative Term.

Version 1.4

  • Variables added
    State Legislative Measures
    sen_prop_up - Proportion of State Senate Seats up for Reelection This Year
    sen_elections_this_year State Senate Elections This Year? (1= 19% or more of Seats up, 0= Fewer than 19% up)
    sen_dem_in_sess - Number of Democrats in the State Senate this Session
    sen_rep_in_sess - Number of Republicans in the State Senate this Session
    sen_ind_in_sess - Number of Non-major Party members in the State Senate this Session
    sen_vac_in_sess - Number of Vacant Seats in the State Senate this Session
    sen_tot_in_sess - Total Number of state Senators this Session
    sen_cont_alt - Party in Control of State Senate ( 1= Democrats, 0= Republicans, .5=Tie)
    hs_prop_up - Proportion of State House Seats up for Reelection This Year
    hs_elections_this_year - State House Elections This Year? (1= 19% or more of Seats up, 0= Fewer than 19% up)
    hs_dem_in_sess - Number of Democrats in the State House this Session
    hs_rep_in_sess - Number of Republicans in the State House this Session
    hs_ind_in_sess - Number of Non-major Party members in the State House this Session
    hs_vac_in_sess - Number of Vacant Seats in the State House this Session
    hs_tot_in_sess - Total Number of state House Members this Session
    hs_cont_alt - Party in Control of State Senate ( 1= Democrats, 0= Republicans, .5=Tie)
    veto_override_prop - Proportion of Legislators Needed to Override Governor Veto
    veto_override_prop_elected - Who does Override Proportion Pertain to? (1= Elected Senators, 0= Present Senators)
    leg_cont - Democrats Power of the legislature (1= Democrats Control Both Chambers; 0= Democrats Control Neither Chamber; .5= Democrats Control One Chamber, .25= Demcorats Split Control of One Chamber, .75= Democrats Control One Chamber and Split Control of the Other)
    split_leg - Is there a Split Legislature (1= Chamber are Not Controlled by Same Party, 0= Else)
    divided_gov - Is there Divided Government? (1= Two Chambers of Legislature and Governorship are not all Controlled by Same Pary, 0= Same Party Controls All Three Institutions)
    sen_dem_prop_all - Proportion of State Senate Seats Held by Democrats
    sen_rep_prop_all - Proportion of State Senate Seats Held by Republicans
    hs_dem_prop_all - Proportion of State House Seats Held by Democrats
    hs_rep_prop_all - Proportion of State House Seats Held by Republicans
    per_leg_of_govs_pty - Percent of Legislature Across the Two Chambers that are of the Same Party as the Governor
    dem_veto_proof - Do Democrats Have Enough Members in Both Chambers to Override a Governor's Veto?
    rep_veto_proof - Do Republicans Have Enough Members in Both Chambers to Override a Governor's Veto?
    dem_unified - Is there a Unified Democratic Government (1= Democrats control both Legislative Chambers and Governorship, 0= else)

    LGBT Equality Measures
    giexorder - Does State have Executive Order Prohibiting Discrimination on the Basis of Gender Identity
    gilaw - Does State have a Law Prohibiting Discrimination on the Basis of Gender Identity
    soexorder - Does State have Executive Order Prohibiting Discrimination on the Basis of Sexual Orientation
    solaw - Does State have a Law Prohibiting Discrimination on the Basis of Sexual Orientation

    Demography Measures
    evangelical_pop - Percentage of Evangelical Residents in a State

    State Fiscal Measures
    spending_stfunds_perincome - Spending from state funds as a percent of state personal income
    spending_fedfunds_perincome - Spending from federal funds as a percent of state personal income
    employ_pop - Rolling Employment to Population Ratio
    change_proptax - Change in Property Tax Revenue from the Previous Year
    change_bustax_other - Change in Other Business Taxes and Fees Revenue from Previous Year
    change_utiltax - Change in Public Utility Tax Revenues from Previous Year
    change_amustax - Change in Amusement Tax Revenues from Previous Year
    change_docstocktax - Change in Document & Stock Transfers Tax Revenues from Previous Year
    change_corptax - Change in Corporate Income Tax Revenues from Previous Year
    change_corplicrev - Change in Corporate Licenses Revenue from Previous Year
    change_salestax - Change in Sales Tax Revenue from Previous Year
    change_incometax - Change in Personal Income Tax Revenue from Previous Year
    change_sevtax - Change in Severance Tax Revenue from Previous Year
    change_fueltax - Change in Fuel Tax Revenue from Previous Year
    change_tobtax - Change in Tobaccco Tax Revenue from Previous Year
    change_vehtax - Change in Motor Vehicles Tax Revenue from Previous Year
    change_stincometax - Change in Personal State Income Tax Revenue from Previous Year
    fedshare_rev - Federal Share of State Revenue
    med_spending_own - Medicaid Spending Divided By Own-Source Revenue
    dayreserve_genfund - Days' worth of General Fund expenditures in reserve
    endingbal_rainyday - Ending balance plus Rainy Day Funds (in millions)
    res_genfund - Reserves as a percent of General Fund expenditures

Version 1.3

  • Variables added
    State Electoral Campaign Contributions
    nonindiv_contrib - 
    Total contributions to State candidates from non-individuals (e.g. labor unions, parties and candidates, business, PACs, etc.)
    contrib_to_incumbs  -  Total contributions to all Incumbent candidates running for State offices
    contrib_to_dems -  Total contributions to all Democratic candidates running for State offices
    contrive_to_reps -  Total contributions to all Republican candidates running for State offices
    contrib_to_thirdparty -  Total contributions to all Third Party candidates running for State offices
    contrib_agri -  Total contributions to State Office candidates from contributors in the agricultural sector
    contrib_candidates -  Total contributions to State Office candidates from other candidates
    contrib_comm_elec -  Total contributions to State Office candidates from contributors in the communications and electronics sector
    contrib_construction -  Total contributions to State Office candidates from contributors in the construction sector
    contrib_defense -  Total contributions to State Office candidates from contributors in the defense sector
    contrib_energy_natres -  Total contributions to State Office candidates from contributors in the energy and natural resources sector
    contrib_gov_ed_other -  Total contributions to State Office candidates from contributors in government agencies, education, and other sectors
    contrib_health -  Total contributions to State Office candidates from contributors in the health sector
    contrib_ideo_singiss -  Total contributions to State Office candidates from contributors in the ideology and single issue sectors
    contrib_labor -  Total contributions to State Office candidates from contributors in the labor sector
    contrib_lawyer_lobby -  Total contributions to State Office candidates from contributors in the lawyer and lobbyist
    contrib_transp -  Total contributions to State Office candidates from contributors in the transportation sector
    contrib_unitemized -  Total contributions to State Office candidates from unitemized contributors
    contrib_fin_ins_realestate -  Total contributions to State Office candidates from contributors in the finance, insurance, real estate sector
    contrib_public_subsidy -  Total contributions to State Office candidates from public subsidies
    contrib_business - Total contributions to State Office candidates from contributors in the general business sector
    contrib_party - Total contributions to State Office candidates from political parties

Version 1.2

  • Variables added
    gov_contrib-
    Contributions to Governor’s Races
    house_contrib- Contributions to State House/Assembly Races
    senate_contrib- Contributions to State Senate Races
    court_contrib- Contributions to State Supreme Court Races
    ballot_contrib-Contributions to Ballot Measure Committees
    dem_contrib- Contributions to the State Democratic Party
    rep_contrib- Contributions to the State Republican Party
    acounty> - Total Number of County Level Governments in the State
    amuni - Total Number of Municipal Level Governments in the State
    atown - Total Number of Township Level Governments in the State
    mood - Measure of Stimson’s Policy Mood
    democrat - Proportion of Voters Identifying as Democratic
    republican - Proportion of Voters Identifying as Republican
    liberal - Proportion of Voters Identifying as Liberal
    conservative - Proportion of Voters Identifying as Conservative

Version 1.1

  • Interest group variables fixed to match original source. The data was originally misaligned due to a sorting error.
  • Variables added:
    afdc_rep -
    Average Monthly Number of Total Recipients of AFDC/TANF within a year.
    afdc_case -
    Average Monthly Number of Total Family Caseloads for AFDC/TANF within a year.
    foodstamp_rep - Average Monthly Number of Persons Receiving Food Stamps/SNAP within a year.
    foodstamp_case - Average Monthly Number of Total Caseloads for Food Stamps/SNAP within a year.
    stateminState Minimum Wage in dollars
    povrateEstimated Percent of State Population in Poverty
  • State FIPS code for Idaho corrected from 46 to 16.
  • Minor test fixes in codebook to add clarity to some variables.

Variables Included:

I.          POLICY OUTPUTS           

(policy liberalism; policy innovativeness; policy priorities; year of statehood; when states adopted policies on abortion, criminal justice, drugs and alcohol, education, environment, gambling, gay rights, governmental issues, gun control, immigration, labor rights, licensing, miscellaneous regulations, racial discrimination, taxes, transportation, welfare and health care, women’s rights, among others)    

II.        CRIMINAL JUSTICE

(motor vehicle theft rate and totals, property crime rate and totals, robbery crime rate and totals, murder crime rate and totals, violent crime rate and totals, gun background checks)

III.       DEMOGRAPHIC     

(state population, population density, population under 5 years old, population between 5 and 17 years old, population between 18 – 24 years old, population between 25 – 44 years old, population between 45 – 64 years old, population over 65 years old, population over 85 years old, female population, male population, religion, ethnicity, number of licensed drivers, abortion rate, divorce rate, birthrate, number of new immigrants receiving green cards, number of new refugees, political knowledge, social capital)

IV.       ECONOMIC AND FISCAL 

(personal income, disposable personal income, state minimum wage, per capital income, state consumer price index, regional / national consumer price index, housing price index, gross state product, total state debt, total state revenue, general state revenue, state tax revenue, total expenditures, fiscal year, legislative operating expenditures, legislative construction expenses, legislative capital expenditures, legislative equipment expenditures, legislative total expenditures, budget surplus estimates, total debt outstanding as percent of GDP, total revenue outstanding as percent of GDP, general revenue as percent of GDP, tax revenue as percent of GDP, total expenditures as percent of GDP, general expenditures as percent of GDP, budget surplus as percent of GDP, total debt outstanding as percent of personal income, total revenue as percent of personal income, general revenue as percent of personal income, tax revenue as percent of personal income, total expenditures as percent of personal income, general expenditures as percent of personal income, budget surplus as percent of personal income, percent change in real per capita income, state tax capacity, state tax effort index, regulatory freedom, economic freedom, fiscal freedom, personal freedom, overall freedom scores and rankings, gun control freedom, alcohol freedom, marijuana and salvia freedom, travel freedom, gambling freedom, civil liberties freedom, education freedom, asset-forfeiture freedom, victimless crime freedom, marriage freedom, campaign finance freedom, tobacco freedom, land-use freedom, labor market freedom, health insurance freedom, cable and telecommunications freedom, occupational licensing freedom, tort freedom, tax freedom, state assets, state liabilities, unfunded pension and other employee benefit liabilities, cash solvency index, long-run solvency index, budget solvency index, service level solvency index, trust fund solvency index, fiscal condition index, women’s earnings as a percentage of men’s earnings, value of agricultural sector, unemployment rate, tax revenue from corporations, number of patents, median household income, lottery ticket sales, lottery prize amounts, lottery administrative costs, income per capita, gross state product per capita, gross state product total, direct governmental farm payments, food stamp benefits, poverty rate, AFDC/TANF recepients, AFDC/TANF caseloads, foodstamps/SNAP recepients, foodstamps/SNAP caseloads, social service participation, welfare spending, number of business firms, number of bankruptcy filings, among others)

V.        EDUCATION

(state education spending, percent of state population with a high school diploma, average school attendance rate, average daily school attendance rate, percent dropout rate, instruction expenses as percent of total education expenditures, instruction expenses per student, pupil to teacher ratio, total education expenses, total number of enrolled students, fourth grade math scores, fourth grade reading scores, among others)

VI.       ELECTION   

(number of votes in general election, voting eligible population turnout rate, total population eligible to vote, number of felons ineligible to vote, state electoral competitiveness measures, proportion of state senate seats up for election, proportion of state house seats up for election, proportion of democratic state senators, proportion of two-party vote for Democratic gubernatorial candidate, party control of state government, Ranney measures of electoral competitiveness, average winning percent and margins by winning candidate, percent of "safe" seats, Holbrook and Van Dunk measures of electoral competitiveness, Shufeldt and Flavin's measures of electoral competitiveness, election contributions, campaign finance regulation, among others)

VII.     ENERGY AND ENVIRONMENT 

(commercial sector energy consumption, commercial sector energy consumption per capita, residential sector energy price, total CO2 emissions from fossil fuels, among others)

VIII.    GOVERNMENT (GOVERNOR, LEGISLATURE, STATE HIGH COURT)      

(election years, governor names, gubernatorial changes, prior public service of governor, state term limits, female governor, party of the governor, lame duck governor, midterm penalty, open seat, number of local governments, state house ideological median, state senate ideological median, state House Democratic Party ideological median, state House Republican Party ideological median, state Senate Democratic Party ideological median, state Senate Republican Party ideological median, distance between party medians in state House, distance between party medians in state Senate, average ideological distance between any two members in state House, average ideological distance between any two members in state Senate, Democratic Party heterogeneity in State House, Democratic Party heterogeneity in state Senate, Republican Party heterogeneity in State House, Republican Party heterogeneity in state Senate, chamber ideological heterogeneity, state legislative professionalism, percent of state legislators that are female, ADA/COPE measure of state government ideology, Nominate measure of state government ideology, state high court professionalism, corruption, among others)

IX.       HEALTH       

(total state population with government insurance, total state population without government insurance, total population with private health insurance, health spending per capita, infant mortality rate, medicaid enrollment and spending, among others)

X.        INTEREST GROUP 

(state interest group density, number of state education interest groups, number of agriculture and fisheries interest groups, number of banking and real-estate interest groups, number of insurance interest groups, number of manufacturing interest groups, number of construction and housing interest groups, number of legal and courts interest groups, number of small business and retail interest groups, number of health care interest groups, number of civil rights and minority issue interest groups, number of hotel and restaurant interest groups, number of environmental protection interest groups, number of churches and religious organizations, number of welfare interest groups, number of commercial resource development interest groups, number of good governance interest groups, number of women's issues interest groups, number of utilities and energy interest groups, number of tax and government regulations interest groups, number of media and communication interest groups, number of transportation and transit interest groups, number of intergovernmental relations interest groups, number of police and fire interest groups, number of sports and entertainment interest groups, number of service firms interest groups, number of military and veterans interest groups, number of unclassified interest groups, union density, among others)

XI.       PUBLIC OPINION, PARTISANSHIP, IDEOLOGY         

(Berry et al. citizen ideology measure; Erickson, Wright and McIver (EWM) party identification score, EWM weighted state ideology score, EWM state party identification score, EWM state ideology score, Stimson’s policy mood, among others)

 

This aggregated data set is only possible because many scholars and students have spent tireless hours creating, collecting, cleaning, and making data publically available. Variable names, descriptions, dates, and notes are generally copied directly from the source. For complete information about the variable, how it was collected or calculated, see the original source. Attribution for a variable should be given to the named source(s). However, we would also appreciate recognition. 

Suggested Citation:

Jordan, Marty P. and Matt Grossmann. 2016. The Correlates of State Policy Project v.1.10. East Lansing, MI: Institute for Public Policy and Social Research (IPPSR). 

Send errors or new datasets to: correlatesofstatepolicyproject@gmail.com