Concerns about Reproducibility, Use of the Akaike Information Criterion, and Related Issues in Hoondert et al. 2019
Get accessExtract
To the Editor:
Estimating species sensitivity distributions (SSDs) is a promising approach that is increasingly used to derive predicted no‐effect concentrations for chemicals in ecological risk assessment. Given the difficulty of and limitations in generating ecotoxicological data, seeking quantitative structure–activity relationship (QSAR) approaches to estimating SSDs is valuable. The recent article by Hoondert et al. (2019) is pioneering in that they developed QSAR‐based models to estimate means and standard deviations (SDs) of SSDs based on acute and chronic toxicity data.
Hoondert et al. (2019) selected a total of 4 models to predict means and SDs of acute and chronic SSDs and then discussed the importance of the predictors included in the models. However, we failed to reproduce their model selection results (i.e., Table 3 of Hoondert et al. [2019]) because their description of the method is not sufficiently detailed. Because they state that "the most parsimonious models were...selected...based on the corrected Akaike information criterion as well as the adjusted R2," we infer that they used both the corrected Akaike information criterion (AICc; Burnham et al. [2011]) and adjusted R2 values for model selection. Assuming that this inference is correct, we raise 2 major concerns about the use of statistical methods and the interpretation thereof by Hoondert et al.: 1) If the AIC(c) is used in determining the "best" model, then the (adjusted) R2 should not also be used for model selection; and 2) Even if the AIC(c) is used correctly to determine the "best" model, final conclusions on the importance of predictors should not be based on this "best" model alone. An additional minor concern, which would likely have had no effect on their general findings, is that AICc values cannot be compared between models developed with different response variables.
Sign in
-
Society of Environmental Toxicology and Chemistry
Society of Environmental Toxicology and Chemistry members
Sign in through society site Arrow
Personal account
- Sign in with email/username & password
- Get email alerts
- Save searches
- Purchase content
- Activate your purchase/trial code
- Add your ORCID iD
Get help with access
Institutional access
Access to content on Oxford Academic is often provided through institutional subscriptions and purchases. If you are a member of an institution with an active account, you may be able to access content in one of the following ways:
IP based access
Typically, access is provided across an institutional network to a range of IP addresses. This authentication occurs automatically, and it is not possible to sign out of an IP authenticated account.
Sign in through your institution
Choose this option to get remote access when outside your institution. Shibboleth/Open Athens technology is used to provide single sign-on between your institutionâ€TMs website and Oxford Academic.
- Click Sign in through your institution.
- Select your institution from the list provided, which will take you to your institution's website to sign in.
- When on the institution site, please use the credentials provided by your institution. Do not use an Oxford Academic personal account.
- Following successful sign in, you will be returned to Oxford Academic.
If your institution is not listed or you cannot sign in to your institutionâ€TMs website, please contact your librarian or administrator.
Sign in with a library card
Enter your library card number to sign in. If you cannot sign in, please contact your librarian.
Society Members
Society member access to a journal is achieved in one of the following ways:
Sign in through society site
Many societies offer single sign-on between the society website and Oxford Academic. If you see †̃Sign in through society siteâ€TM in the sign in pane within a journal:
- Click Sign in through society site.
- When on the society site, please use the credentials provided by that society. Do not use an Oxford Academic personal account.
- Following successful sign in, you will be returned to Oxford Academic.
If you do not have a society account or have forgotten your username or password, please contact your society.
Sign in using a personal account
Some societies use Oxford Academic personal accounts to provide access to their members. See below.
Personal account
A personal account can be used to get email alerts, save searches, purchase content, and activate subscriptions.
Some societies use Oxford Academic personal accounts to provide access to their members.
Viewing your signed in accounts
Click the account icon in the top right to:
- View your signed in personal account and access account management features.
- View the institutional accounts that are providing access.
Signed in but can't access content
Oxford Academic is home to a wide variety of products. The institutional subscription may not cover the content that you are trying to access. If you believe you should have access to that content, please contact your librarian.
Institutional account management
For librarians and administrators, your personal account also provides access to institutional account management. Here you will find options to view and activate subscriptions, manage institutional settings and access options, access usage statistics, and more.
Purchase
Short-term Access
To purchase short-term access, please sign in to your personal account above.
Don't already have a personal account? Register