It is extremely important for a researcher to clearly define the variables in a study because this helps to determine the type of analysis that can be performed on the data. for example, if a researcher wanted to describe countriescountries based on isbn left parenthesis international standard bookisbn (international standard book number right parenthesis group identifiernumber) group identifier, what level of measurement would the variable "isbn group identifierisbn group identifier" be? now suppose the researcher felt that certain countries who were farthercountries who were farther northnorth received higher identifying numbersidentifying numbers. does the level of measurement of the variable change? if so, how?

The ISBN numbers given to countries are nominal data as they function only as identifiers and merely used to tell one country from the other as regards ISBN numbers. Nominal measurements are categorical and are seen as names such as I would name 2 persons person 1 and person 2 respectively. Ordinal values are given with condition such that they are given based on certain order. example the countries are given ISBN numbers based on how farther away they are from the north