Structures of hadron-induced showers observed by the Pamir thick lead chambers are compared with simulations. The simulations are made for several models, VENUS, QGSJET, HDPM and the modified UA5 model, for hadron–nucleus interactions. A parameter Z , which is related to the inelasticity of hadron–Pb interactions, is defined and the Z -distribution of experimental data is compared with those of the simulations applying the same procedure of data processing to both sets of data. The Z -distribution for single-isolated hadrons is well reproduced by the models (VENUS, QGSJET and modified UA5) which give an average inelasticity 〈K h – Pb 〉=0.7 –0.8, whereas that for multi hadrons is close to the HDPM model which gives a smaller inelasticity of 〈K h – Pb 〉=0.5 –0.6. The difference of the characteristics between the two categories of hadron-induced showers is discussed.
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