--- title: Agreement over Time description: Understand how EKO Q uses Agreement over Time to assess dataset differences, review bias metrics, and visualise irradiance data consistency across time scales. --- [![EKO Q](https://eko-support.eko-instruments.com/hs-fs/hubfs/EKO%20Q%20Logo%201-2.png?height=75&width=248&name=EKO+Q+Logo+1-2.png)](https://eko-support.eko-instruments.com/knowledge-base?hsLang=en) EU | A | あ ⌄ English Deutsch Português Español [EKO website](https://eko-instruments.com) [EKO Q](https://eko-q.eko-instruments.com) [Contact us](https://share-eu1.hsforms.com/1MNfi6yWgQ6ab174lgwH9XA2eqp93) Search # How can we help you? Your browser does not support the video tag. 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[Detailed Report and plots](https://eko-support.eko-instruments.com/knowledge-base/understand-reports-and-plots?hsLang=en#detailed-report-and-plots) # Agreement over Time Agreement over Time focuses on how the difference between the two datasets evolves over time. It provides key metrics commonly used to assess agreement between datasets, together with plots that visualise the differences at different time scales. These results help you review the data directly and identify patterns that may require further investigation.![](https://eko-support.eko-instruments.com/hs-fs/hubfs/image-png-May-29-2026-03-18-52-4277-PM.png?width=670&height=95&name=image-png-May-29-2026-03-18-52-4277-PM.png) **Mean bias**, **annual bias**, and **monthly bias** represent the average difference between the datasets over the available data period. They are calculated for the full dataset, per year, and per month, respectively. The separation between all-sky conditions and data filtered as almost clear-sky provides additional detail. Keep in mind that these values only represent the available data and may be significantly affected by data gaps, abnormal values, and filtering criteria. **Caution:** The metrics provided in this section only represent the apparent relationship between the datasets. They should not be used to judge sensor performance without careful review of the detailed results and further investigation into the causes of any mismatch. **Reference values** are provided for convenience and give an approximate indication of what may generally be considered small deviations. For more accurate guidance, always consult a trusted advisor and consider the specific requirements of your application and measurement setup. ![](https://eko-support.eko-instruments.com/hs-fs/hubfs/image-png-May-29-2026-03-29-39-3323-PM.png?width=670&height=264&name=image-png-May-29-2026-03-29-39-3323-PM.png) See more details on how to read*[Carpet Plots](https://eko-support.eko-instruments.com/knowledge-base/how-to-read-and-understand-the-carpet-plot?hsLang=en)* and the [Understand the Absolute Irradiance Difference plot.](https://eko-support.eko-instruments.com/knowledge-base/understanding-the-absolute-irradiance-difference-full-sky-plot?hsLang=en) To complement the time-based comparison with an overall correlation view, see [**General Linearity**](https://eko-support.eko-instruments.com/knowledge-base/general-linearity?hsLang=en). - [Start here](https://eko-support.eko-instruments.com/knowledge-base/start-here?hsLang=en) - [Set up your EKO Q workspace](https://eko-support.eko-instruments.com/knowledge-base/set-up-your-eko-q-workspace?hsLang=en) - [Import and check data](https://eko-support.eko-instruments.com/knowledge-base/import-and-check-data?hsLang=en) - [Run analysis](https://eko-support.eko-instruments.com/knowledge-base/run-analysis?hsLang=en) - [Understand reports and plots](https://eko-support.eko-instruments.com/knowledge-base/understand-reports-and-plots?hsLang=en#main-content) - [Report overview](https://eko-support.eko-instruments.com/knowledge-base/understand-reports-and-plots?hsLang=en#report-overview) - [Test Summary](https://eko-support.eko-instruments.com/knowledge-base/understand-reports-and-plots?hsLang=en#test-summary) - [Detailed Report and plots](https://eko-support.eko-instruments.com/knowledge-base/understand-reports-and-plots?hsLang=en#detailed-report-and-plots) - [Troubleshooting and limits](https://eko-support.eko-instruments.com/knowledge-base/troubleshooting-and-limits?hsLang=en#main-content) - [Upload troubleshooting](https://eko-support.eko-instruments.com/knowledge-base/troubleshooting-and-limits?hsLang=en#upload-troubleshooting) - [Plans, limits, and coverage](https://eko-support.eko-instruments.com/knowledge-base/troubleshooting-and-limits?hsLang=en#plans-limits-and-coverage) [![Logo\_primary logo+tagline\_email size\_RGB](https://eko-support.eko-instruments.com/hs-fs/hubfs/Logo_primary%20logo+tagline_email%20size_RGB.png?width=194&height=43&name=Logo_primary%20logo+tagline_email%20size_RGB.png "Logo_primary logo+tagline_email size_RGB")](http://eko-instruments.com) [eko-instruments.com](https://eko-instruments.com/) Copyright © 2025, eu.eko-instruments.com ![EKO Instruments](https://eko-instruments.com/wp-content/uploads/2024/05/EKO-footer-logo.svg) ## Contact & Customer Support - E: eko-q@eko-instruments.com Certificates: ![ASTM certificate](https://eko-instruments.com/wp-content/uploads/2025/10/astm-cert.svg) ![ISO certificate](https://eko-instruments.com/wp-content/uploads/2025/10/iso-cert.svg) ![IEC certificate](https://eko-instruments.com/wp-content/uploads/2025/10/iec-cert.svg) ![HMEI certificate](https://eko-instruments.com/wp-content/uploads/2025/10/hmei-cert.svg) © 2026 EKO Instruments Co., Ltd. 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