The indirect scaling into the customer satisfaction : An approach based on the alternative use of the exponential and the normal distribution

In order to generate the values associated to the judgements expressed into the customer satisfaction, the psycometric method uses the normal distribution. In a few conditions this function is the cause of preposterous values, that distort the scaling procedure. In case of frequencies concentrated on the extreme categories, the assumption of the exponential, instead of the normal distribution, improves the judgements scaling. An approach, based on the alternative use of the standard normal and exponential distribution is developed; it gives good results.