A method for exchanging data between entities (6, 7, 8), the method comprising the steps of: - providing a prediction model configured to predict the class of an element among a set of classes based on a descriptor vector (x) of the element, each descriptor vector (x) comprising a set of descriptive variables (x i), - receiving a descriptor vector (x) of a first element, the descriptor vector (x) coming from a first entity, the receiving step being implemented by a receiving unit of a second entity, - predicting the class of the first element by the prediction model based on the descriptor vector (x) of the first element, the prediction step being implemented by computer, - determining, in order to obtain the class of the first element, the contribution of each descriptive variable (x i) of the first element, the determining step being implemented by computer of the second entity, - selecting a subset of descriptive variables (x i) of the first element whose contribution satisfies a preponderance criterion relative to the contributions of the set of descriptive variables (x i) of the first element, the selection step being implemented by computer of the second entity, - determining, if necessary, at least one second element based on the descriptor vector (x) of the first element, of the class predicted for the first element and of the selected subset of descriptive variables (x i) of the first element, the determining step being implemented by computer of the second entity, the second element verifying the following conditions: - the distance between the descriptor vector (x) of the first element and the descriptor vector (x) of the second element is less than a predetermined threshold, - at least one descriptive variable (x i) of the second element has a value different from the corresponding descriptive variable (x i) of the first element and belongs to the selected subset of descriptive variables (x i) of the first element, and - the image of the descriptor vector (x) of the second element by the prediction model is a class different from the class of the first element, - sending, by a transmission unit of the second entity, to a third entity, the descriptor vector (x) of the first element, the class of the first element and, where appropriate, the descriptor vector (x) of the second element and the class of the second element. - providing a prediction model configured to predict the class of an element among a set of classes based on a descriptor vector (x) of the element, each descriptor vector (x) comprising a set of descriptive variables (x i), - receiving a descriptor vector (x) of a first element, the descriptor vector (x) coming from a first entity, the receiving step being implemented by a receiving unit of a second entity, - predicting the class of the first element by the prediction model based on the descriptor vector (x) of the first element, the prediction step being implemented by computer, - determining, in order to obtain the class of the first element, the contribution of each descriptive variable (x i) of the first element, the determining step being implemented by computer of the second entity, - selecting a subset of descriptive variables (x i) of the first element whose contribution satisfies a preponderance criterion relative to the contributions of the set of descriptive variables (x i) of the first element, the selection step being implemented by computer of the second entity, - determining, if necessary, at least one second element based on the descriptor vector (x) of the first element, of the class predicted for the first element and of the selected subset of descriptive variables (x i) of the first element, the determining step being implemented by computer of the second entity, - the distance between the descriptor vector (x) of the first element and the descriptor vector (x) of the second element is less than a predetermined threshold, - at least one descriptive variable (x i) of the second element has a value different from the corresponding descriptive variable (x i) of the first element and belongs to the selected subset of descriptive variables (x i) of the first element, and - the image of the descriptor vector (x) of the second element by the prediction model is a class different from the class of the first element, - sending, by a transmission unit of the second entity, to a third entity, the descriptor vector (x) of the first element, the class of the first element and, where appropriate, the descriptor vector (x) of the second element and the class of the second element.