Methodical Problems of Comparative Studies

N, large-V” problem
The Galton’s problem
The problem of measurement
The problem of

interpretation

identical, and therefore comparative politics runs into a difficulty when

it wants to compare the ‘same phenomena’ or ‘similar objects’ in different countries.
Two strategies to deal with this problem are available:
• looking for more abstract concepts
• looking for equivalent concepts

Problem of Equivalence in Comparative Research. Political Analysis, 19(4). P. 473.

in Fig. 1 . Panel A shows a comfortable state

of the survey research world where no item bias exists. That an individual j living in country k responds differently from an individual living in country к' is completely due to the fact that they have different preferences (njk != n’jk’). Panel В shows the opposite situation. Now our two individuals share the same level of preference or attitude strength (njk = njk’), but their responses differ due to the systematic country differences discussed above. Clearly, the differences between those individuals are not real but the result of country method effects, so that latent preferences cannot be compared between countries.

that is, they have a tendency to select only one

side of the scale (usually the one indicating agreement). Some countries produce extreme responders, who consistently choose extreme ends of scales, whereas in other countries, individuals predominantly choose the middle part of a response scale - avoiding strong statements (Yang et al. 2010). In consequence, this means that two individuals sharing the same level of preference may answer survey questions differently, simply because one of them is from a country where an extreme response style is common. Scores from individuals from different countries are then no longer directly comparable since they are systematically biased (Millsap and Kwok 2004). In other words, the dependent variable lacks equivalence.

available:
The Ladder of Abstraction
Retest

number of cases (n) required for comparisons grows exponentially. Therefore,

only a few explanatory variables are often too many for the relatively small number of cases available, in which case an empirical test is not possible.
Strategies to deal with this problem are available:
increase the number of cases;
limiting the number of variables.

statistician, progressive, polymath, sociologist, psychologist, anthropologist, eugenicist, tropical explorer, geographer,

inventor, meteorologist, proto-geneticist, and psychometrician.

problems. First, it might bias the results; second, it affects

statistical analyses by making the size of the sample of independent cases uncertain.

strategies to deal with this problem are available:
To change attitude

towards history and histortical method
Scientific Realism

the actual epistemic status of theories (or some components thereof),

and this is described in a number of ways (in terms of the epistemic achievements constituted by scientific theories). 
That is, some think of the position in terms of what science aims to do: the scientific realist holds that science aims to produce true descriptions of things in the world (or approximately true descriptions, or ones whose central terms successfully refer, and so on) (in terms of the epistemic aims of scientific inquiry).