Before revision:  However, the variety and complexity of these procedures can limit the ability of ecologists to formulate and fit their own SSMs. In addition, many SSM users are unaware of the potential estimation problemsthey could encounter, and of the model selection and validation tools that can help them assess how well their models fit their data.
After revision:  However, the variety and complexity of these procedures can limit the ability of ecologists to formulate and fit their own SSMs. We provide the knowledge for ecologists to create SSMs that are robust to common, and often hidden, estimation problems, and the model selection and validation tools that can help them assess how well their models fit their data.