Instructions for Authors

*Version date: September 2026* These instructions tell you how to prepare your manuscript for submission to CAS Forum. They cover submission limits, manuscript structure, citations and references, tables and figures, and a short section for authors writing in LaTeX. You do not need any other document to prepare your submission. If a question comes up that these instructions don't answer, contact us—see Section 7, Questions. CAS Forum is a nonrefereed publication. Papers are reviewed by the Forum Working Group, but manuscripts do not undergo a double-blind peer review. Anyone may submit a paper to CAS Forum. You do not need to be a CAS member. Your paper's content must be relevant to the property-casualty actuarial community.

1. Before You Submit — Quick Reference Checklist

Check your manuscript against this list before you submit it: - File format: Word or LaTeX for your manuscript, plus a PDF copy of the final version. - Length: **about 10,000 words**. - Pages: **50 pages or fewer**, as you intend the manuscript to appear in print. This includes any appendices you want published as part of the formatted article—see Section 2, What a Finished Forum Paper Looks Like, for appendices you don't need in that count. - Tables and figures: **30 total, combined**. This is one combined count across every table, figure, exhibit, or similar element in your paper—not 30 of each. - Table files: Tables can be edited in Word or LaTeX. **DO NOT** upload screenshots of Excel spreadsheets as tables. - Block equations: **20 maximum**. This applies only to equations set on their own line. Equations written inline within a sentence don't count toward this limit. - Abstract: **150 words or fewer**, required. - Keywords: **2–7 keywords**, required. - Reference style: **Chicago Manual of Style, 18th edition, author-date system**—see Section 4, Citing Your Sources. - Tables and figures: **every one must be numbered and called out by number in your text**—see Section 3, Tables and Figures. - Images: **clear, high-resolution files**—see Section 3, Tables and Figures.

2. What a Finished Forum Paper Looks Like

Most Forum papers follow the structure below. Use it as a starting template. Minor variation is fine where it serves your content, but this is the shape your editor will expect to see. The numbered body sections (Introduction through Conclusion) are shown below as a typical example only. Use as many or as few numbered sections as you need to describe your research. > *Title (title case)* > > *Byline* > > *Abstract (one or two short paragraphs of plain prose, 150 words or fewer—no "Motivation / Results / Conclusions" style subheadings)* > > *Keywords: [Term], [Term], [Term]* > > *1. Introduction (research context, objective, and an outline of the paper)* > > *2. Background and methods* > > *3. Results and discussion* > > *4. Conclusion* > > *Acknowledgments (optional, unnumbered)* > > *AI Use Disclosure (optional, unnumbered)* > > *Financial Support Statement (optional, unnumbered)* > > *References (required, alphabetical, unnumbered)* > > *Appendix A. [Title] (lettered; only if needed)* A few structural notes: - The Introduction and Conclusion are numbered sections. - Section numbers follow the pattern 1, 1.1, 1.2, with a period after the final digit in a heading (for example, "2.1. Model selection."). It is best to avoid going beyond three subheading levels, i.e., avoid breaking text down into Section 1.2.3.4. and beyond. - Appendices are always lettered (Appendix A, Appendix B), even when there's only one. Never just "Appendix." If there are subheadings within an appendix, use numbers. For example, Appendix A.2. - Order your appendices by where you first mention them in your text. - Section and subsection headings use sentence case: capitalize only the first word, the first word after a colon, and proper nouns. - Use articles published on the Forum website (forum.casact.org) as your reference for how headings should look, not the downloaded PDF. Here is what this looks like in a finished paper: > **Comparing Chain Ladder and Bornhuetter-Ferguson Reserve Estimates for Commercial Auto Liability** > > *[author names removed]* > > **Abstract:** This paper compares chain ladder and Bornhuetter–Ferguson reserve estimates for a commercial auto liability line of business, using 10 years of loss triangle data. The two methods converge at older maturities but diverge in the three most recent accident years. We show how the initial expected loss ratio selection drives this divergence, and we offer guidance for choosing between the two methods. > > **Keywords:** Loss reserving, Chain ladder, Bornhuetter–Ferguson, Commercial auto liability, IBNR > > 1. Introduction > > 2. Background and methods > > 2.1. Data and triangle construction > > 2.2. Chain ladder method > > 2.3. Bornhuetter–Ferguson method > > 3. Results and discussion > > 4. Conclusion > > References > > Appendix A. Loss triangle detail by accident year

Appendices and supplemental files

You may want to include an appendix or appendices in your manuscript. Appendices appear after your references, are copyedited and formatted like the rest of your paper, and count toward the 50-page limit described in Section 1. If an appendix is too long, or doesn't need to be formatted for print, indicate in your cover letter that it should be published as a supplemental file. Content posted this way does not count toward your page limit, but it is not edited or formatted. It appears exactly as you submit it. Supplemental files are available for public download from the Data Sets/Files tab on all published articles. ![The Data Sets/Files tab, as it appears to readers on a published article.](https://www.casact.org/sites/default/files/2026-09/Data-Sets-UI-image.png) Supplemental files may also include material that was never part of your manuscript at all, such as raw datasets, R or SAS code, or other supporting files, which you believe might be helpful for readers interested in further reading or exploration. Either way, you are responsible for the quality of anything published as a supplemental file. If you want to refer to a supplemental file in your manuscript, mention it at the point where it would otherwise appear and call it out specifically as a supplemental file. For example: > *Appendix B and the R code are available in the Data Sets/Files tab at the top of this article's page.*

3. Tables and Figures

Choosing a numbering system: the Rule of Five

Before you number a single table or figure, count them first. The Rule of Five decides how your whole manuscript numbers tables and figures. It applies to every table, figure, exhibit, or similar element in your paper, not just one category. - Find whichever category appears most often in your manuscript: tables, figures, exhibits, or another term. - Count how many times elements in that category appear. - If the count reaches five or more, use section-based numbering for every category in the paper (for example, Table 3.1 or Figure 3.2), even for a category with only one item. - If no category reaches five, use simple sequential numbering for every category instead (Table 1, Table 2, Figure 1, Figure 2, and so on). - Apply one system to the whole manuscript. You may not number tables one way and figures another. Whichever category is largest sets the system for everything. Section-based numbering follows the top-level section, not the subsection. Numbering continues through every subsection beneath that section without resetting. For example: Section 3.1 contains one table. That table is Table 3.1. Section 3.1.1 then adds two more tables. They continue the same sequence: Table 3.2 and Table 3.3, even though they sit in a different subsection. Section 3.4.2, later in the same main section, adds four more tables. Those become Table 3.4 through Table 3.7. Tables and figures keep separate sequences, so figures in that section start their own count.

Labeling: what to call it

You may use "Figure" or a more descriptive term instead. Exhibit, Chart, Graph, and similar terms all work, as long as the term fits your content and you use it consistently. "Table" itself is never renamed. The Rule of Five still applies to whichever term you use.

Calling out tables and figures in your text

Every table and figure needs a title, ending in a period: "Table 1. Illustration of loss development patterns." Every one must be called out by its number somewhere in your text. Your text callouts set where tables and figures land in the page proofs. Call out tables and figures in order. Do not skip numbers. Avoid examples like this when Tables 3 and 4 have not already been mentioned in text: "Tables 1, 2, and 5 show the data from the analysis." You may reference appendix tables out of sequence, but do so only sparingly. Figure titles belong in your manuscript as a caption in the text, not in the image file. If your figure's image file already has a title on it, remove or crop it out before you submit. The caption in your manuscript text is what readers will see as the title. Always refer to a table or figure by number, not by its position on the page or its content. Avoid "the following table," "the table above," "the table below," "the loss triangle," etc. Your editor will remove these during copyediting if you use these kinds of directional identifiers. If a note appears below a table or figure that isn't part of the surrounding running text, preface it with "*Note:*" in italics, with the rest of the note text in plain roman type.

Example: correct and incorrect callouts

The following three examples show the difference between a table or figure that's properly called out and one that isn't. ![Incorrect: the table and figure are never called out by number anywhere in the text, and neither one has a title or number to identify it.](https://www.casact.org/sites/default/files/2026-09/Author-Instruct-IFA-wrongcallout1.png) ![Incorrect: "the table below" and "the following figure" describe position on the page instead of naming a number, and neither element has a title or number to identify it.](https://www.casact.org/sites/default/files/2026-09/Author-Instruct-IFA-wrongcallout2.png) ![Correct: the text calls out "Table 3" and "Figure 2" by number, and both elements carry a numbered title/caption.](https://www.casact.org/sites/default/files/2026-09/Author-Instruct-IFA-correct-callout.png)

Calling out equations

Always precede an equation number with the word "equation": - **Correct:** "You can see that equation (5.1) produces the following results..." - **Incorrect:** "You can see that (5.1) produces the following results..."

Connecting your figure files to your manuscript

When you send in figure files, follow these rules, whether you write in Word or LaTeX: - Give each figure a real, descriptive file name, not just a generic one. "demand_curve.png" tells no one what the figure shows or which one it is. "Fig-6-linear-demand-damping-curves.png" does—it still works as a file name, but the figure number makes it easy to match against your manuscript, especially in a package with many figures or ones that didn't make the final cut. - Upload each figure as a single file. If a figure has multiple parts or panels (e.g., a, b, c), combine them into one image before you upload it. - Upload only the figures that appear in your manuscript. - Submit images as JPEG or PNG files. Make sure they are clear and high resolution. - CAS will only work with the figure files you supply. We do not redraw, enhance, or otherwise edit your images.

4. Citing Your Sources

Building a citation: the basic pattern

CAS Forum uses the Chicago Manual of Style author-date system. Most citations follow this pattern: (Author's last name Year). - One author: (Venter 2019). - Two authors: (Venter and Gao 2019). - Three or more authors: (Venter et al. 2019). - No named author, such as an organization report: use the organization's name instead. (Casualty Actuarial Society 2019).

In-text citations

A few more patterns cover most other cases: - Multiple sources: separate with a semicolon. (Smith and Lee 2004; Norman 1999). - Multiple works by the same author: separate with a comma. (Taleb 2001, 2007). - Multiple works by the same author published in the same year: separate with a comma, use alphabetical labeling. (Taleb 2001a, 2001b). - Naming the author in your sentence: "According to Norman (2003), the most accurate..."

Reference list

List references alphabetically by last name. Never number them. Italicize books and journal names. Put article and chapter titles in quotation marks. A few common examples: > Book: Isaacson, W. 2011. *Steve Jobs*. New York: Simon and Schuster. > > Journal article: Campbell, J. L., and O. K. Pedersen. 2007. "The Varieties of Capitalism and Hybrid Success." *Comparative Political Studies* 40 (3): 307–32. > > Web page: Google. 2023. "Privacy Policy." *Privacy & Terms*. Effective November 15. https://policies.google.com/privacy. > > Software: R Core Team. 2024. *R: A Language and Environment for Statistical Computing* (Version 4.4.1) [Computer software]. R Foundation for Statistical Computing. https://www.r-project.org/. > > Repository: Casualty Actuarial Society. 2025. *bias-toolbox*. GitHub repository, commit a1b2c3d, accessed August 4, 2026. https://github.com/casact/bias-toolbox. For software or a code repository, first check whether it has a published paper. If so, cite that paper instead. Only cite software or a repository directly when you rely on its contents as evidence for a claim. If you're only using it as a tool, a plain mention with a version number is enough ("analysis was performed in R, version 4.4.1") and doesn't need a References entry.

Mentioning a title in your writing

When you refer to another work by name within a sentence—not in a citation, just in your prose—style it like this: italicize books and journal names, for example, "As detailed in *Loss Models: From Data to Decisions*..."; put an article title in quotation marks and italicize the journal it appeared in, for example, Mack's "Distribution-Free Calculation of the Standard Error of Chain Ladder Reserve Estimates," published in *ASTIN Bulletin*; and leave standards documents like Actuarial Standards of Practice in plain roman type, with no italics or quotation marks. If your source type doesn't fit the patterns above, style it as closely as you reasonably can. The test: could a reader locate your source with minimal effort from what you've given them? If so, don't worry about getting every comma exactly right. If you're genuinely unsure how to handle an unusual source, contact us—see Section 7, Questions.

5. Other Formatting Essentials

The editors will address the following elements in text, but you can also make these changes yourself while writing your paper. - Numbers: spell out one through nine. Use numerals for 10 and up. If a number under 10 appears in the same comparison as a number 10 or over, use numerals for both ("3 of the 12 models," not "three of the 12 models"). - Abbreviations: spell out on first use, with the abbreviation in parentheses, then use the abbreviation alone afterward. Don't introduce an abbreviation for the first time in a heading. Expand it there, and introduce the short form the first time it appears in your running text. - Capitalization: lowercase by default. Capitalize trademarks, formal office and department names, and the first word after a colon in a title or heading. - Punctuation: use a serial comma ("item one, item two, and item three"). - "Versus" and "data": spell out "versus" in running text ("vs." is fine in tables and figures only). Treat "data" as a plural noun ("the data are consistent with...," not "the data is...").

6. If You're Writing in LaTeX

CAS prefers **biblatex** for your citations. If you're starting a new manuscript, use this method. If you're already using **natbib** in an existing manuscript, you can keep using it instead. Don't mix the two methods in one document—pick one.

Option 1: biblatex (preferred)

Add these two lines to your preamble: ``` \usepackage[authordate]{biblatex-chicago} \addbibresource{yourfile.bib} ``` Replace "yourfile.bib" with the name of your own .bib file. Add `\printbibliography` where you want your reference list to appear. This usually goes near the end of your document. **Common citation commands:**

To get...	Use...
Wilson (2008) argues that...	`\textcite{key}`
...as shown (Wilson 2008).	`\parencite{key}`
(Wilson 2008, 15)	`\parencite[15]{key}`
(Wilson 2008; Jones 2019)	`\parencite{key1,key2}`
(see, for example, Smith 2020)	`\parencite[see, for example,][]{key}`

**This method needs a program called biber, not the older bibtex program.** - In Overleaf, this happens automatically. You don't need to do anything. - If you compile on your own computer, biber must run as its own step. Your compile order should be: ``` pdflatex → biber → pdflatex → pdflatex ``` Running only pdflatex will not update your citations, even if you run it several times. Check your editor's build settings to confirm it runs biber, not bibtex.

Option 2: natbib (if you're already using it)

Add these lines to your preamble: ``` \usepackage[round]{natbib} \bibliographystyle{chicago} \bibliography{yourfile} ``` Leave off the ".bib" ending in this last line. LaTeX adds it automatically. Add natbib to your preamble before the `\bibliographystyle{chicago}` line. If you skip this, author names may print garbled or repeated. **Common citation commands:**

To get...	Use...
Wilson (2008) argues that...	`\citet{key}`
...as shown (Wilson 2008).	`\citep{key}`
(Wilson 2008, p. 15)	`\citep[p.~15]{key}`
(Wilson 2008; Jones 2019)	`\citep{key1,key2}`
(see, for example, Smith 2020)	`\citep[see, for example,][]{key}`

This method needs a file called chicago.bst. Most systems (including Overleaf) already have it. If your compile fails with a "chicago.bst not found" error, contact us and we'll help.

Your .bib file (either method)

Both methods read the same kind of file: a plain-text list of your sources, saved with a .bib ending. Your .bib file should only include works cited in your paper. Two things matter here: - Give every entry its own unique key (the short label right after the {, like smith2020). If two entries share a key, one will silently overwrite the other. - Write author names as Last, First (for example, Wilson, James) and join multiple authors with the word "and." Get this wrong and author names may print oddly in your reference list.

When you submit your manuscript

Send the complete package for typesetting: - Your .tex file(s) - Your .bib file - Any figure or image files your manuscript uses - A PDF of your compiled manuscript, so we can confirm it matches your source files Only include what actually appears in your final PDF. Leave out unused figures or old files. Your .bib file should match what produced your final bibliography, not an earlier draft.

7. Questions?

These instructions cover what most Forum authors need. If something about your manuscript isn't addressed here, contact editor@variancejournal.org.

Extrapolating, Smoothing and Interpolating Development Factors [Discussion]