Unsure Calculator is a simple web-based calculator that handles uncertain inputs. Instead of precise numbers, users input estimated ranges (e.g., "100 to 200") or distributions (e.g., "normal(100, 10)"). The calculator then performs the requested arithmetic operations (add, subtract, multiply, divide) and displays the resulting probability distribution of possible outcomes, visualized as a histogram. This allows users to quickly see the range and likelihood of different outcomes when dealing with imprecise estimations, making it useful for back-of-the-napkin calculations involving uncertainty.
The Hacker News post titled "Show HN: Unsure Calculator – back-of-a-napkin probabilistic calculator" introduces a web-based calculator designed for performing calculations with uncertain or imprecise numerical inputs. Instead of relying on single, definite values, the Unsure Calculator allows users to input ranges or distributions of possible values, reflecting the inherent uncertainty often present in real-world estimations. This is achieved through a syntax that allows users to express uncertainty directly within the calculation itself, for example, using "~" to denote an approximate value or specifying ranges with curly braces like "{100..200}". The calculator then propagates this uncertainty through the calculation, providing not just a single answer, but a distribution of likely outcomes. This distribution is visualized as a histogram, offering a clear and intuitive representation of the range of possible results and their respective probabilities. The aim is to facilitate more realistic and nuanced calculations, acknowledging the inherent imprecision in many estimations and providing a more comprehensive understanding of the potential range of results, rather than just a single, potentially misleading, point estimate. The calculator is presented as a lightweight and easily accessible tool, akin to performing quick, approximate calculations on the back of a napkin, but with the added capability of handling uncertainty in a structured and visually informative manner. It's implied that this tool can be valuable for quick estimations, sensitivity analysis, and decision-making under uncertainty, particularly in scenarios where precise data is unavailable or impractical to obtain.
Summary of Comments ( 134 )
https://news.ycombinator.com/item?id=43690289
HN users generally praised the Unsure Calculator for its intuitive approach to dealing with uncertainty in calculations. Several commenters highlighted its potential usefulness in various fields, from project management and cost estimation to personal finance and everyday decision-making. Some suggested improvements, like adding support for distributions beyond normal distributions, and integration with other tools. The clean UI and ease of use were also commended, though one user pointed out a potential ambiguity in the syntax. The developer engaged with the comments, responding to suggestions and clarifying usage. A few commenters also discussed broader implications of embracing uncertainty in calculations and the importance of tools like this for better decision-making.
The Hacker News post discussing the "Unsure Calculator" has generated a fair number of comments, exploring various aspects and potential improvements of the tool.
Several commenters appreciate the simplicity and user-friendliness of the calculator, praising its intuitive syntax and ease of use for quick, probabilistic calculations. They find the ability to express uncertainty directly within calculations particularly helpful. One commenter even suggests integrating it into a spreadsheet environment, highlighting its potential for broader application.
A common thread among the comments involves discussing alternative approaches and existing tools for similar probabilistic computations. Commenters mention libraries like
uncertaintiesin Python and point to existing Monte Carlo simulation techniques as more robust solutions for complex scenarios. They acknowledge the Unsure Calculator's niche as a lightweight tool for simpler estimations, contrasting it with the more comprehensive functionalities of established libraries.The discussion also delves into the specific implementation details of the calculator, including the choice of the PERT distribution for representing uncertainty. Some commenters question this choice and propose alternative distributions or methods for defining uncertainty ranges. A detailed discussion ensues regarding the implications of using different distributions and their impact on the final results.
Furthermore, commenters explore potential improvements and extensions to the calculator's functionality. Suggestions include adding support for correlations between variables, implementing different aggregation methods, and providing more visualizations for the probability distributions. The possibility of incorporating unit handling and error propagation analysis is also raised.
Finally, a few comments focus on the user interface and user experience, proposing enhancements like improved display of results, better handling of edge cases, and more comprehensive documentation. The overall sentiment is positive, with commenters recognizing the value of the Unsure Calculator as a convenient tool for simple probabilistic estimations while acknowledging the potential for further development and refinement.