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The operator effect is a well-known analytical bias already quantified in some taphonomic studies. However, the influence of operator bias in the replicability on taphonomic studies has still not been considered. Here, we quantified for the first time this bias using different multivariate statistical techniques, testing if the operator effect is related to the replicability. We analyzed the results reported by 15 operators working on the same dataset. Each operator analyzed 30 bioclasts (bivalve shells) by site, from a total of five sites, considering the following taphonomic attributes: shell fragmentation, edge rounding, corrasion, bioerosion, and color alteration. The operator effect followed the same pattern reported in previous studies, characterized by a worse correspondence for those attributes having more than two levels of damage categories. However, the effect did not appear to have relation to replicability, because nearly all operators found differences among sites. The binary attribute bioerosion exhibited 83% of correspondence among operators, but at the same time it was the taphonomic attribute that showed the highest dispersion among operators (28%). Therefore, we concluded that binary attributes, despite indicating a reduction of the operator effect diminishes replicability, resulting in different interpretations of concordant data. We found that a variance value of nearly 8% among operators was enough to generate a different taphonomic interpretation, in a Q-mode cluster analysis. The results reported here showed that the statistical method employed influences the level of replicability and comparability of a study and that the availability of results may be a valid alternative to reduce bias. ; Fil: Do Nascimento Ritter, Matias. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: Francischini, Heitor. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: Kuhn, Lidia Aumond. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: Da Luz, Nathália Carvalho. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: Michels, Fernando Heck. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: De Morais, Anderson Luiz Martins. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: Paim, Protásio Antônio Vervloet. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: Xavier, Pedro Luis Ammon. Universidade Federal do Rio Grande do Sul; Brasil ; Fil: de Francesco, Claudio German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina