Many scientists are interested in but puzzled by the various inverse power laws with a negative exponent 1 such as the rank-size rule. The rank-size rule is a very simple scaling law followed by many observations of the ubiquitous empirical patterns in physical and social systems. Where there is a rank-size distribution, there will be a hierarchy with cascade structure. However, the equivalence...

background: general practitioners are the first who visit burn patients and they first calculate burn size and required fluid for the patient. error in calculation can be disastrous. the purpose of this study is to compare four methods of estimating burn size to teach students. methods: this is a descriptive-analytic study on 37 medical students. four methods of estimating burn percentage was t...

Letting ) (i S be the i-th largest city in a country, it is often observed that i S i log log 1 0 ) ( α α + ≈ for some 0 0 > α and 0 1 < α . It is called rank size rule when 1 1 − = α . This relationship has been examined by means of ordinary least squares estimation and t test in the literature. However, since ) (i S is heteroskedastic and autocorrelated, t statistics do not have standard dist...