Teaching Microeconometrics using at Warsaw School of Economics Marcin Owczarczuk Monika Książek Agenda • What is microeconometrics • Microeconometrics – the lecture • How do we teach: • Ordinal outcome models • Count outcome models • Limited outcome models Microeconometrics • Microdata • Individuals • Households • Companies • Microeconometrics = econometrics for microdata • Fields of application: • Marketing • Finance • Social science Microeconometrics – the lecture • • • • • • 15 lectures (2h each) Theory + applications Applications on publicly avaiable datasets Calculations in STATA Maximum likelihood Binary, multinomial, ordinal, count, limited dependent variables • Cross-sectional data only Ordinal outcome models Data • European Social Survey, vawe 3, Poland • Ordinal dependent variable (ocdoch): Which of the descriptions on this card comes closest to how you feel about your household’s income nowadays? 1 Living comfortably on present income 2 Coping on present income 3 Finding it difficult on present income 4 Finding it very difficult on present income • Independent variables: • Continous AGE (wiek) • Binary CHILDREN (dzieci) • Nominal (3 categories) PROFESSION (zawód: kierownicy, pracownicy) OLOGIT, OPROBIT, GOLOGIT Significance testing: • Single variable • Variable set • Whole model Parallel regressions assumption testing • Wolfe & Gould • Brant • LR ologit vs gologit Assumption holds standard model is OK Model quality assessment • Model fit • Predictive capacities predict prob1, outcome(1) Parameters interpretation • Compensating effect • Marginal effect • Odds ratio Count outcome models Data .4 .2 0 Density .6 .8 • CBOS survey: Living conditions of Polish people – problems and strategy • Dependent variable: number of small children (up to 6 year old) in a young family (20-35 year old) 0 2 4 V344 6 Poisson regression Negative binomial regression (allows for overdispersion).... No overdispersion Poisson model is OK Zero inflated (Poisson) model (Poisson model) (Binary logit model: P(Y=0)) ZIP fits better than standard Poisson model Limited outcome models Data • PVA (US not-for-profit organisation) which rises funds by direct mailings • Donors differ in amounts and frequencies of gifts • Explanatory variables • history of previous mailings • characteristics of the donor’s neighbourhood Tobit regression Target_d – amount given in last mailing (many zeros) Truncated regression Target_d – amount given in last mailing (no zero observations) Sample selection, maximum likelihood Positive correlation – who gives more, gives less frequently Significant correlation Srednia_odleglosc – average distance (in days) between gifts; sredni_datek – average amount selekcja =1 if more than 6 gifts were given Sample selection, two step Inverse Mills ratio