Comparing approaches to ecological meta-analysis
Contributed by: an NCSU student and Paula Pappalardo @pau_pappalardo
Keywords
Climate change, Conservation, Ecology, Environmental change, Fundamental research, Global patterns, Latino/a/x, Theory/Computational, Woman
Slides
Note: click the gear symbol to see notes that accompany the presentation
View and download in google slides here.
Resources
Pappalardo Paula., K. Ogle, E.A. Hamman, J.R. Bence, B.A. Hungate, & C. W. Osenberg 2020. Comparing traditional and Bayesian approaches to ecological meta‐analysis. Methods in Ecology and Evolution 11.10: 1286-1295. Find article here.
You can also learn more about Paula through a Scientist Spotlight here.
Notes
Slide 1: Researcher’s Background
Dr. Pappalardo is a marine ecologist at the Smithsonian Environmental Research Center. She uses a variety of data sources to study the drivers of broad-scale patterns in marine biodiversity.
PB: Why did you become a biologist?
PP: I always loved animals and wanted to know all about them (what they are, where they live, why they live there).
PB: What is your favorite part about your job?
PP: I like that I can always learn new things and meet new people. And also that there are always new challenges and problems to be solved.
PB: What obstacles have you overcome to get where you are?
PP: I can think of two: 1) I worked through most of my college experience and that sometimes meant that I did not have a lot of free time to do additional extracurricular activities that could have been useful for my career.; 2) having a foreign accent can be tricky sometimes with people that are not used to it, especially on a high stakes situation (e.g., a job interview) or when teaching.
PB: What advice do you have for aspiring biologists?
PP: Make a plan early if you can, to guide you about what opportunities will be the most useful and find good mentors that can help you with that. Never be afraid of asking people for advice. Most people will love to help you and will provide free advice.
PB: Do you feel that any dimension of your identity is invisible or under-represented/marginalized in STEM?
PP: Maybe
PB: Can you elaborate on your answer above?
PP: In my field (Ecology) I have not felt marginalized as a latina, although there have been a few awkward occasions with someone not understanding my accent or someone making a joke that was not very thoughtful. I think latinas may be underepresented in high level positions; however in terms of gender balance for tenure track positions in my field, my impression is that things look good or improving.
Slide 2: Research Overview
Take home message of study
Meta-analysis is a statistical technique, often used in ecology, that combines the results of multiple scientific studies to determine an overall effect or trend. In this paper, Dr. Pappalardo and her colleagues compared two methods of measuring error and effect sizes across published ecological meta-analyses on topics related to climate change. They discovered that many meta-analyses did not report the methods used to calculate important metrics or used potentially problematic methods encoded in software defaults. They also determined that some meta-analyses likely overestimated significance of their results, particularly when the number of studies in the analysis was low. These findings suggest that authors need to adopt more appropriate methods for ecological meta-analysis and take greater care when choosing settings in statistical software.
Study system
This figure summarizes a literature review of ecological meta-analyses, including the number of studies included in the meta-analyses and the number of replicates within those studies. Ecological studies often have much fewer replicates than studies in disciplines with more well-established techniques for meta-analysis (e.g. medicine), which may make it difficult to assess the robustness of ecological meta-analysis using the same methods developed in other disciplines.
Slide 3: Key Research Points
Main figure
This figure shows the different types of uncertainty intervals reported in ecological meta-analysis papers. Many papers did not report the method used to quantify uncertainty levels at all; these papers likely used the default methods in their respective meta-analysis software.
Societal Relevance
This paper demonstrates that the statistical methods used to synthesize studies can have a profound effect on the conclusions drawn. It is important that scientists critically evaluate and properly report their methods, especially when their results could have policy implications (as with these meta-analyses related to climate change!). It is also important for developers of meta-analysis programs to provide written training or guidance for various settings and approaches.
