The present disclosure relates to a question recommending method, apparatus, and system. The method includes: constructing, by a server, an interest vector of a user according to a short-term interest, a long-term interest, and a group interest of the user, the interest vector of the user including multiple interest items; acquiring a candidate-for-recommendation question from a set of to-be-resolved questions according to the multiple interest items; estimating, according to a click-through rate (CTR) model, probability of answering the candidate-for-recommendation question by the user, and selecting a to-be-recommended question according to the estimated probability; and sending the to-be-recommended question to a client. In this way, a real-time comprehensive recommendation result can be obtained, and a question answering rate of an interactive question-and-answer platform can also be improved.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A question recommending method, comprising: constructing, by a server, an interest vector of a user according to a short-term interest, a long-term interest, and a group interest of the user, the interest vector of the user comprising multiple interest items, further comprising combining the short-term interest, the long-term interest, and the group interest of the user according to a vector weighting coefficient of the short-term interest of the user, a vector weighting coefficient of the long-term interest of the user, and a vector weighting coefficient of the group interest of the user and by means of linear weighting of vectors, to obtain the interest vector of the user; acquiring, by the server, at least one candidate-for-recommendation question from a set of to-be-resolved questions according to the multiple interest items; separately estimating, by the server according to a click-through rate (CTR) model, a probability of answering the at least one candidate-for-recommendation question by the user; selecting, by the server, a to-be-recommended question from the at least one candidate-for-recommendation question according to the estimated probability; and recommending the to-be-recommended question to a client of the user. 2. The method according to claim 1, before the constructing an interest vector of a user according to a short-term interest, a long-term interest, and a group interest of the user, further comprising: calculating the short-term interest of the user according to real-time answer records of the user within predetermined duration prior to a current time. 3. The method according to claim 1, before the constructing an interest vector of a user according to a short-term interest, a long-term interest, and a group interest of the user, further comprising: calculating the group interest of the user according to historical answer records, attributes of the user, and an occurrence probability of an interest item corresponding to each attribute of the user. 4. The method according to claim 1, before the constructing an interest vector of a user according to a short-term interest, a long-term interest, and a group interest of the user, further comprising: establishing the CTR model according to historical answer records and historical exposure records. 5. The method according to claim 2, wherein the calculating the short-term interest of the user according to real-time answer records of the user within predetermined duration prior to a current time comprises: acquiring the real-time answer records of the user within the predetermined duration prior to the current time; extracting, according to the real-time answer records, an interest item corresponding to each question and a time at which each question is answered, and constructing a circular queue by using the time at which each question is answered as a timestamp of the interest item corresponding to the question, by using the interest item as an element, and according to the timestamp corresponding to the interest item; calculating a weight corresponding to each interest item according to the circular queue; and calculating the short-term interest of the user according to the weight corresponding to each interest item. 6. The method according to claim 3, wherein the calculating the group interest of the user according to historical answer records, attributes of the user, and an occurrence probability of an interest item corresponding to each attribute of the user comprises: classifying all users into groups of different types according to the attribute combination of the user; calculating an occurrence probability of each interest item corresponding to the attribute combination of the user; calculating weights of interest items corresponding to the group of each type according to the probability; searching for a group corresponding to the user according to the attributes of the user; and calculating the group interest of the user according to weights of interest items corresponding to the group. 7. The method according to claim 1, wherein the vector weighting coefficient of the short-term interest of the user is greater than the vector weighting coefficient of the long-term interest of the user, and the vector weighting coefficient of the long-term interest of the user is greater than the vector weighting coefficient of the group interest of the user, wherein the vector weighting coefficient of the short-term interest of the user is greater than or equal to 0.5 and less than or equal to 0.8, the vector weighting coefficient of the long-term interest of the user is greater than or equal to 0.1 and less than or equal to 0.5, and the vector weighting coefficient of the group interest of the user is greater than or equal to 0.1 and less than or equal to 0.5. 8. The method according to claim 4, wherein the step of establishing a CTR model according to historical answer records and historical exposure records comprises: marking a question, which has been answered by the user, in the historical exposure records as a positive sample, and marking a question, which has not been answered by the user, in the historical exposure records as a negative sample; extracting feature vectors of all positive samples and negative samples; and performing CTR model training by using the feature vectors of the positive samples and the negative samples, to establish the CTR model. 9. The method according to claim 1, wherein the acquiring at least one candidate-for-recommendation question from a set of to-be-resolved questions according to the multiple interest items comprises: calculating correlation between questions in the set of to-be-resolved questions and the interest vector of the user according to the multiple interest items; sorting the questions according to the correlation; and extracting a question whose correlation is in a predetermined range as the candidate-for-recommendation question. 10. The method according to claim 1, wherein the estimating, according to a CTR model, a probability of answering the candidate-for-recommendation question by the user comprises: extracting a feature vector of the user, a feature vector of the candidate-for-recommendation question, and a feature vector of a current scene; and estimating, by using the feature vectors and the CTR model, the probability of answering the candidate-for-recommendation question by the user. 11. A question recommending apparatus, comprising: an interest vector calculation module, configured to construct an interest vector of a user according to a short-term interest, a long-term interest, and a group interest of the user, the interest vector of the user comprising multiple interest items, wherein the interest vector calculation module further comprises: an interest vector calculation sub-unit, configured to combine the short-term interest, the long-term interest, and the group interest of the user according to a vector weighting coefficient of the short-term interest of the user, a vector weighting coefficient of the long-term interest of the user, and a vector weighting coefficient of the group interest of the user and by means of linear weighting of vectors, to obtain the interest vector of the user; a candidate-for-recommendation question acquiring module, configured to acquire at least one candidate-for-recommendation question from a set of to-be-resolved questions according to the multiple interest items; a to-be-recommended question acquiring module, configured to separately estimate, according to a click-through rate (CTR) model, a probability of answering the candidate-for-recommendation question by the user, and select a to-be-recommended question from the at least one candidate-for-recommendation question according to the estimated probability; and a question recommending module, configured to recommend the to-be-recommended question to a client of the user. 12. The apparatus according to claim 11, further comprising: a short-term interest calculation unit, configured to calculate the short-term interest of the user according to real-time answer records of the user within predetermined duration prior to a current time. 13. The apparatus according to claim 11, further comprising: a long-term interest acquiring unit, configured to acquire the long-term interest of the user according to historical answer records. 14. The apparatus according to claim 11, further comprising: a group interest calculation unit, configured to calculate the group interest of the user according to historical answer records, attributes of the user, and an occurrence probability of an interest item corresponding to each attribute of the user. 15. The apparatus according to claim 11, further comprising: a CTR model establishing unit, configured to establish the CTR model according to historical answer records and historical exposure records. 16. The apparatus according to claim 12, wherein the short-term interest calculation unit comprises: a real-time answer records acquiring sub-unit, configured to acquire the real-time answer records of the user within predetermined duration prior to the current time; a circular queue constructing sub-unit, configured to extract, according to the real-time answer records, an interest item corresponding to each question and a time at which each question is answered, and construct a circular queue by using the time at which each question is answered as a timestamp of the interest item corresponding to the question, by using the interest item as an element, and according to the timestamp corresponding to the interest item; a first weight calculation sub-unit, configured to calculate a weight corresponding to each interest item according to the circular queue; and a short-term interest calculation sub-unit, configured to calculate the short-term interest of the user according to the weight corresponding to each interest item. 17. The apparatus according to claim 14, wherein the group interest calculation unit comprises: a group classification sub-unit, configured to classify all users into groups of different types according to an attribute combination of the user; a probability calculation sub-unit, configured to calculate an occurrence probability of each interest item corresponding to the attribute combination of the user; a second weight calculation sub-unit, configured to calculate weights of interest items corresponding to the group of each type according to the probability; a search sub-unit, configured to search for a group corresponding to the user according to the attributes of the user; and a group interest calculation sub-unit, configured to calculate the group interest of the user according to weights of interest items corresponding to the group. 18. The apparatus according to claim 11, wherein the vector weighting coefficient of the short-term interest of the user is greater than the vector weighting coefficient of the long-term interest of the user, and the vector weighting coefficient of the long-term interest of the user is greater than the vector weighting coefficient of the group interest of the user, wherein the vector weighting coefficient of the short-term interest of the user is greater than or equal to 0.5 and less than or equal to 0.8, the vector weighting coefficient of the long-term interest of the user is greater than or equal to 0.1 and less than or equal to 0.5, and the vector weighting coefficient of the group interest of the user is greater than or equal to 0.1 and less than or equal to 0.5. 19. The apparatus according to claim 11, wherein the candidate-for-recommendation question acquiring module comprises: a correlation calculation unit, configured to calculate correlation between questions in the set of to-be-resolved questions and the interest vector of the user according to the multiple interest items; a first sorting unit, configured to sort the questions according to the correlation; and a candidate-for-recommendation question selection unit, configured to extract a question whose correlation is in a predetermined range as the candidate-for-recommendation question. 20. The apparatus according to claim 11, wherein the to-be-recommended question acquiring module comprises: an estimation unit, configured to estimate, according to the CTR model, the probability of answering the candidate-for-recommendation question by the user; a second sorting unit, configured to sort the candidate-for-recommendation question according to the estimated probability; and a to-be-recommended question selection unit, configured to extract a question whose probability is in a predetermined range as the to-be-recommended question.