Abstract: In a prediction device, an acquisition means acquires a feature quantity related to a well of shale gas or shale oil. A prediction means calculates a predicted value of a production volume of the well or a sand return amount of the well, based on the feature quantity, using a machine learning model. An output means outputs the predicted value and a contribution degree of the feature quantity to the predicted value.

Abstract: [Object] Provided are a 11C-labeled acyclic retinoid that can be synthesized in a short time with a high yield and can be suitably used for PET for elucidating intracerebral kinetics, a PET probe using it, and methods for producing them. [Solution] The 11C-labeled acyclic retinoid of the present invention is characterized by being represented by the following chemical formula (a). This compound can be produced by a coupling step of cross-coupling a methyl iodide labelled with 11C and the following organotin compound (b) (provided that in the formula, R1 and R2 represent alkyl groups which may have a branch) in an aprotic solvent in the presence of a palladium complex, a phosphine ligand, and a cuprous halide.