Semiparametric models encompass a huge family of models that have a fully parametric (finite number of parameters) with a nonparametric part. In general, the parametric part will be linear, and the semiparametric part will be treated as nuisance; but this is not always the case. One example where a semiparametric model would be relevant, could be for example modeling the ice-cream sales in terms of the weather and the price. It's likely that the sales-weather relationship is highly nonlinear (sales are really high when the temperature is high, but low when the temperature is moderate), whereas the price-sales one could be quite linear. In that case, we would want to treat the price effect as linear and the rest as nuisance.
United States
Great Britain
India
Germany
France
Canada
Russia
Spain
Brazil
Australia
Singapore
Hungary
Ukraine
Luxembourg
Estonia
Lithuania
South Korea
Turkey
Switzerland
Colombia
Taiwan
Chile
Norway
Ecuador
Indonesia
New Zealand
Cyprus
Denmark
Finland
Poland
Malta
Czechia
Austria
Sweden
Italy
Egypt
Belgium
Portugal
Slovenia
Ireland
Romania
Greece
Argentina
Netherlands
Bulgaria
Latvia
South Africa
Malaysia
Japan
Slovakia
Philippines
Mexico
Thailand