Analysis apparatus, system, method, and program

An analysis apparatus for calculating an index indicating an optimization degree of a model including information of an electron density distribution with respect to measurement data, a probability distribution function followed by the measurement data being known, comprising:

• processing circuitry configured to
• acquire the measurement data,
• acquire calculation data calculated from the model, and
• calculate an index goodness-of-fit (GOF) including a ratio of a residual, which is defined by a predetermined mathematical formula including the measurement data and the calculation data, and an expected value of the residual, which is defined based on the probability distribution function and the predetermined mathematical formula,
• wherein the predetermined mathematical formula includes a weight parameter that multiplies the measurement data by a constant value when the measurement data has an intensity equal to or less than a predetermined value and that takes a logarithm of the measurement data when the measurement data has an intensity more than the predetermined value.

A method for calculating an index indicating an optimization degree of a model including information of an electron density distribution with respect to measurement data, a probability distribution function followed by the measurement data being known, comprising:

• acquiring the measurement data,
• acquiring calculation data calculated from the model, and
• calculating an index goodness-of-fit (GOF) including a ratio of a residual, which is defined by a predetermined mathematical formula including the measurement data and the calculation data, and an expected value of the residual, which is defined based on the probability distribution function and the predetermined mathematical formula,
• wherein the predetermined mathematical formula includes a sum of squared residuals of a logarithm of the measurement data and a logarithm of the calculation data.

A non-transitory computer-readable storage medium storing computer-readable instructions thereon for calculating an index indicating an optimization degree of a model including information of an electron density distribution with respect to measurement data, a probability distribution function followed by the measurement data being known which, when executed by a computer, causes the computer to perform a method, the method comprising:

• acquiring the measurement data,
• acquiring calculation data calculated from the model, and
• calculating an index goodness-of-fit (GOF) including a ratio of a residual, which is defined by a predetermined mathematical formula including the measurement data and the calculation data, and an expected value of the residual, which is defined based on the probability distribution function and the predetermined mathematical formula,
• wherein the predetermined mathematical formula includes a sum of squared residuals of a logarithm of the measurement data and a logarithm of the calculation data.