Josh Lyons, a Senior at Northland College, and I are reviewing metrics used to measure precision of (or variability among) estimated ages of fish from multiple readings of calcified structures (e.g., percent agreement, CV). In the first part of our work, we are reviewing ~225 published papers (since about 1990) to identify various characteristics of how these metrics have been used in the literature. In a second part of our work, we hope to re-analyze data from published papers to calculate precision metrics that were not used and perform other analyses that were not conducted in the original paper. With results from these two pieces of work, we hope to make recommendations regarding the use and analysis of precision metrics that will address some common issues we have identified in their use.

We are seeking help with two parts of this project. First, we seek raw (i.e., not summarized) data on multiple age estimates from the same structure of each fish. To date we have received approximately 30 data sets but we are looking to diversify the species, regions, structures, and age ranges in our synthesis by soliciting more data sets. Please contact me if you have a data set that you think would be suitable for this analysis and that you are willing to share with us. [Note that we can handle a variety of data types and will tidy the data to meet a specific format for our needs. So far, authors that have provided us data have simply provided us their raw data files without any further munging, except to explain the meaning of some variables to us.]

Note that it is not our intent to verify your results (though we will likely recalculate your results, among other calculations), nor will we specifically discuss/critique your paper in our review. Rather, our intent is to analyze these data to provide results that will feed into a synthetic summary. If we ultimately pursue publication of our review, we would like to make all of our data, including your raw data, publicly available so that others can replicate or further our analyses. If you would like us to NOT make your raw data publicly available, then let us know and we will honor that request.

Second, please bring publications to our attention that have estimated age precision (in some way), have been published since 1990, and are NOT on our current list.

Let me know if you can help us with either of these needs or have any questions. Thank you for considering this request to assist our project.