<div dir="ltr"><div dir="ltr"><div>Dear Chris,</div><div><br></div><div>going back to your original question of "easy to understand resources" I would say this guide by BPA (<a href="https://www.bpa.gov/-/media/Aep/energy-efficiency/measurement-verification/3-bpa-mv-regression-reference-guide.pdf">https://www.bpa.gov/-/media/Aep/energy-efficiency/measurement-verification/3-bpa-mv-regression-reference-guide.pdf</a>). The document includes formulas and corresponding functions in spreadsheets. <br></div><div><br></div><div>In my experience, Variable-Base Degree-Days and Energy Signature models can give essentially the same results if constructed with similar assumptions. The simplest way (in my opinion) to handle piecewise linear shapes and/or shifts in data is to include additional independent "dummy" variables that can help subset the original dataset (e.g. weekday/weekend if you are using daily data, or by day of the week) see this for a general explanation (<a href="https://otexts.com/fpp2/useful-predictors.html">https://otexts.com/fpp2/useful-predictors.html</a>).</div><div><br></div><div>In some cases you may need to include additional variables (e.g. solar radiation for cooling, or enthalpy/HR if air handling processes are involved, etc.) and then compare the models using a stepwise regression approach, to check if the performance in terms of statistical indicators RMSE, R2, CV(RMSE), etc. improves by adding additional independent variables.</div><div><br></div><div>A tool that can automate some of the work (spreadsheet based, with a good documentation and freely available) is ECAM (<a href="https://sbwconsulting.com/ecam/">https://sbwconsulting.com/ecam/</a>), which enables modelling both Energy and Energy Signature. I tested it in some case studies and it works quite well (at least with Excel 2016, not sure about newer versions), even though the hourly model takes some time (ECAM v7.0). <br></div><div><br></div><div>I can provide some indications on the use of the template in case or other Python/R tools that can do a similar work.</div><div><br></div><div>Kind regards,</div><div><br></div><div>MM<br></div><div><br></div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Il giorno mer 15 mar 2023 alle ore 02:36 Shawn Shi via Bldg-sim <<a href="mailto:bldg-sim@lists.onebuilding.org">bldg-sim@lists.onebuilding.org</a>> ha scritto:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>Hello Jeff,</div><div><br></div><div>Thank you kindly for the long reply and history lesson, it's interesting to know BES originated from bomb shelters, there is one still operating not far from where I live :)</div><div><br></div><div>As a gamer growing up, I've always wondered why BES is not voxel-based like minecraft or why we are not using real-time ray-tracing from GPUs for solar insolation computations.</div><div><br></div><div>Anyways, back to model training/calibration. Loss function (in ML training) or cost function (in optimization) is the measuring stick telling the optimization program how to assess the performance of the model. Usually MSE/RMSE is used but it has its limitations, that's why in ML we <a href="https://medium.com/analytics-vidhya/root-mean-square-log-error-rmse-vs-rmlse-935c6cc1802a" target="_blank">sometimes use log errors</a> to deal with outliers. Another example, in fraud detection, we customize loss functions to penalize false negatives harsher than false positives.<br></div><div><br></div><div>Actually many years ago, someone mentioned custom cost function to deal with peak loads for BES calibration, using ExcaliBEM: <a href="https://unmethours.com/question/13182/genoptenergyplus-best-algorithm-for-peak-load-reduction-load-shift/" target="_blank">https://unmethours.com/question/13182/genoptenergyplus-best-algorithm-for-peak-load-reduction-load-shift/</a></div><div><br></div><div>Now on <a href="https://medium.com/@soumyachess1496/cross-validation-in-time-series-566ae4981ce4" target="_blank">cross-validation</a> (CV), it is a wrapper around each model training process to make sure the model is not over-fitting. It is usually the first thing I check when seeing people applying ML models.<br></div><div>In theory these two practices should not interfere with the bounded parameter space.</div><div><br></div><div>Thanks,</div><div>Shawn<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Mar 14, 2023 at 9:05 PM Haberl, Jeff <<a href="mailto:jhaberl@tamu.edu" target="_blank">jhaberl@tamu.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>
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Thanks Shawn:</div>
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Good thoughts. Maybe outside my expertise, but I'll take a crack.</div>
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First, BES are constrained models in that they only allow the user to change cerain parameters and not others. Furthermore, the BES is a preconfigured model of a building that tries to include all the relevant heat transfer properties to the ambient conditions
and the SYSTEM and PLANT reactions to these loads using user-defined inputs.</div>
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This situation only gets worse when on considers that even EP+ was influenced by the original LSPE architecture that was suggested for the Post Office program in the early design of the TACS program. Although EP+ has evolved way beyond the constraints of LSPE
BES programs, the underlying code still has ghosts of this architecture in its algorithms. We recently published one of three new articles for STBE that updates the previous "Origins" articles we published. The first one is "<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">Origins
of whole-building energy simulations for high-performance commercial buildings: Contributions of NATEOUS, SHEP, TACS, CP-26, and RESPTK programs", by Jounghwan Ahn and myself. Two more articles to follow soon in STBE.</span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">In the first article, thanks in part to Jason Glazier for dropping-off a pickup truck's worth of books when Robert Henniger retired, we outline how the early
simulation programs can be traced to simulations of bomb shelters in the 1960s by Tamami Kusuda and Metin Lokmonhekim and the earliest FORTRAN programs that codified response factors by Tamami Kusuda (RESPTK). All of these books are now scanned and can be
found on the <a href="http://onebuilding.org" target="_blank">onebuilding.org</a> website. </span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">In these books you see that what was done in the early days was done because of constraints in the computing hardware in the 1960s and into the 1970s. Unfortunately,
ghosts of this kind of thinking still exist today, with a few exceptions, when we try to define a "thermal zone" as a node that maintains a known temperature given varying internal inputs and external R-C networks that connect the node to the exterior. So,
although we've come a long way, we still have a long way to go to "cut all the stings" to the old LSPE constraints.</span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">Second, there are prototypes of how to move forward into the future, but their "secrets" are highly guarded, which is not good for the general BES community.
However, it is a fact of life and we have to live with it and put our minds to use to reverse engineer what the proprietary codes are doing so we can publish in the public domain so all can see what is done. EP+ is one effort that stands alone it what it has
accomplished AND has accomplished in the public domain -- bravo. </span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">However, there are spectacular proprietary codes that are doing breathtaking simulations that are hidden "behind the wall", and so it goes. </span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">Examples include combined CFM and BES -- a daunting task. Another is full force raytracing and BES programs. Yet another is Urban Scale Building Energy Modeling
(UBEM). All are paths into the future that are critical for BES modelers to learn and incorporate into the work. Finally, there are robo-simuilations that are now being attached to BIM, which is the future for BES. Yet, there is little discussion about public
code, where to get it and whether or not it is worth a hoot.</span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">So, I think BLDG-SIM has a role in providing a public space where "issues" such as the above can be discussed, and vetted in the public domain, so those
who have the development money can get a second opinion about how they are spending state or federal money.</span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">BLDG-SIM can also be seed-corn for student thesis topics since these are like hens teeth when thinking them up and then following through to publication</span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">Just some thoughts.</span></div>
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<span style="color:rgb(0,0,0);font-family:Calibri,Arial,Helvetica,sans-serif;font-size:12pt">Jeff </span></div>
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<p>Jeff S. Haberl, Ph.D., P.E.inactive, FASHRAE,FIBPSA We are like fluttering leaves on the branches of trees</p>
<p>Department of Architecture in the forests of the landscape that surrounds us.</p>
<p>Texas A&M University If we could, for just a moment, flutter together,</p>
<p>College Station, TX 77845-3581 We could lift the earth up to be a better place. JSH 2022</p>
<p>Office: 979-845-6507, Lab: 979-845-6065</p>
<p>Fax 979-862-2457</p>
<p><a href="mailto:jhaberl@tamu.edu,www.esl.tamu.edu" target="_blank">jhaberl@tamu.edu,www.esl.tamu.edu</a></p>
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<div id="m_-698963510867951621m_6998592161605164459divRplyFwdMsg" dir="ltr"><font style="font-size:11pt;color:rgb(0,0,0)" face="Calibri, sans-serif" color="#000000"><b>From:</b> Bldg-sim <<a href="mailto:bldg-sim-bounces@lists.onebuilding.org" target="_blank">bldg-sim-bounces@lists.onebuilding.org</a>> on behalf of Shawn Shi via Bldg-sim <<a href="mailto:bldg-sim@lists.onebuilding.org" target="_blank">bldg-sim@lists.onebuilding.org</a>><br>
<b>Sent:</b> Tuesday, March 14, 2023 7:19 PMGood <br>
<b>To:</b> Dru Crawley <<a href="mailto:dbcrawley@gmail.com" target="_blank">dbcrawley@gmail.com</a>><br>
<b>Cc:</b> <a href="mailto:bldg-sim@onebuilding.org" target="_blank">bldg-sim@onebuilding.org</a> <<a href="mailto:bldg-sim@onebuilding.org" target="_blank">bldg-sim@onebuilding.org</a>><br>
<b>Subject:</b> Re: [Bldg-sim] Lies, darn lies, and statistics</font>
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Hello all, Just a couple thoughts from a random passerby. It’s rare to see this email group this active :p Now please bear with my 2 cents: One thing that always bother me when working on energy model calibration in the past was: why was cross
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<div dir="auto">Hello all,</div>
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<div dir="auto">Just a couple thoughts from a random passerby. It’s rare to see this email group this active :p</div>
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<div dir="auto">Now please bear with my 2 cents:</div>
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<div dir="auto">One thing that always bother me when working on energy model calibration in the past was: why was cross validation (CV) not used?</div>
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<div dir="auto">One fundamental technique in Machine Learning to avoid overfitting is through cross validation. Fitting a complex first-principle model is similar to training a complex black-box model: high degree of freedom, risks of overfitting. CV can be
adopted to avoid incorrect local minima during model training. There are multiple CV approaches for timeseries model training.</div>
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<div dir="auto">And regarding predicting peak loads, etc. When training a model, the loss function (equation that describes model accuracy) dictates how you want the model to behave. Usually RMSE is used but you can customize it to make the model behave in
a certain way better. For example, something like a compound loss function that combines prediction errors from both overall predictions as well as peak prediction. You can adjust the weight for each component to dictate which part is more important than another.</div>
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<div dir="auto">Thanks,</div>
<div dir="auto">Shawn Shi</div>
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<div dir="ltr">On Tue, Mar 14, 2023 at 7:41 PM Dru Crawley via Bldg-sim <<a href="mailto:bldg-sim@lists.onebuilding.org" target="_blank">bldg-sim@lists.onebuilding.org</a>> wrote:<br>
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<div dir="auto">Yep, not me. But I use it a lot.</div>
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<div dir="ltr">On Tue, Mar 14, 2023, 4:19 PM Vikram Sami via Bldg-sim <<a href="mailto:bldg-sim@lists.onebuilding.org" target="_blank">bldg-sim@lists.onebuilding.org</a>> wrote:<br>
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<p>George Box coined that one I think<u></u><u></u></p>
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<p><b>From:</b> Bldg-sim <<a href="mailto:bldg-sim-bounces@lists.onebuilding.org" target="_blank">bldg-sim-bounces@lists.onebuilding.org</a>>
<b>On Behalf Of </b>Jim Dirkes via Bldg-sim<br>
<b>Sent:</b> Tuesday, March 14, 2023 12:13 PM<br>
<b>To:</b> <a href="mailto:chris.malcolm.yates@gmail.com" target="_blank">
chris.malcolm.yates@gmail.com</a><br>
<b>Cc:</b> <a href="mailto:bldg-sim@onebuilding.org" target="_blank">
bldg-sim@onebuilding.org</a><br>
<b>Subject:</b> Re: [Bldg-sim] Lies, darn lies, and statistics<u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">I think Dru Crawley coined the phrase, "All models are wrong. Some are useful."<u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u> <u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">Chris, you highlighted an assortment of variables which are omnipresent, inconsistent and uncontrollable - so what, exactly, does your client expect? Is it a realistic expectation?
For example, are they going to nail you to the wall when, inevitably, you are "wrong" next year?<u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">I have not calibrated many models, but have been made more appreciative of all the uncontrollables by the ones I calibrated :(. All the statisticians know that there is always
more than one solution which will result in a high R2 value or low CVRSME, so which is correct?<u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u> <u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">Rather than a calibrated model, lately I've been encouraging clients to consider one of the FDD platforms on top of their Building Automation System. Spending time and money
to evaluate whether things are working properly makes more sense to me - it's "real life" vs a prediction. (Can't forget to mention thoughtful and thorough commissioning here; that's essential.)<u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u> <u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">ps, I love your thoughtful approach. You're setting a great example! One aspect of that is to reach out to the wider modeling community to gather input and feedback.<u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u> <u style="font-family:Arial,sans-serif"></u></span></p>
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<p style="margin-bottom:6pt"><span><span style="font-size:10.5pt;font-family:Arial,sans-serif;background-color:white;color:rgb(34,34,34)">Jim Dirkes
<a href="https://urldefense.com/v3/__https://www.google.com/maps/search/1631*Acacia*Drive*NW*Grand*Rapids,*MI*49504?entry=gmail&source=g__;KysrKysrKw!!KwNVnqRv!Gyy3l3XXdU0uo6SKEX1uDKDVeqKvb3BM7ELdcAhCyGrNAZnPW1FVt64gzSX8gd4XJkQtPfaNE_z8YgDv9YFrSf_crIA$" style="font-family:Arial,sans-serif" target="_blank">
1631 Acacia Drive NW Grand Rapids, MI 49504</a> - 616 450 8653</span></span><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span><b><span style="font-size:10.5pt;font-family:Arial,sans-serif;background-color:white;color:rgb(34,34,34)">Coffee Conversation:</span></b></span><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span><span style="background-color:white;color:black">The "individual" is an impossible concept, conceived by the Enlightenment philosophers. It makes no sense to the Christian. In marriages, and families, in associations and friendships
and religious orders, we are not individuals, but a communion of persons.</span></span><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u><u style="font-family:Arial,sans-serif"></u></span></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"><u style="font-family:Arial,sans-serif"></u> <u style="font-family:Arial,sans-serif"></u></span></p>
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<p>------- Original Message -------<br>
On Tuesday, March 14th, 2023 at 2:10 PM, <a href="mailto:chris.malcolm.yates@gmail.com" target="_blank">
chris.malcolm.yates@gmail.com</a> <<a href="mailto:chris.malcolm.yates@gmail.com" target="_blank">chris.malcolm.yates@gmail.com</a>> wrote:<br>
<br>
<br>
<u></u><u></u></p>
<blockquote style="margin-top:5pt;margin-bottom:5pt">
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<p>I think I need to qualify this: informed by G14, but definitely not compliant with it! There is some allowance for repairing or “healing” data, but when the data has a lot of holes or modes/ category variables then forget it. This is
my case, but the client still wants some kind of representative simulation.<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>Monthly models can be garbage. School holidays cut across months at different times, combined heat and power is popular which complicates gas usage especially when metering is limited… did the heat by-product of electricity generation
go to the building, or was it rejected? They can work for heating in our temperate climate, but not for cooling.<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>Nevertheless, we need some kind of representative simulation model. We can’t make any ECM qualifying claims but we can do something useful. This is where these methods can give you a lot of insight before you start modelling.<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>I hadn’t tried the IMT previously. We tend to have limited our regression analysis to monthly “degree day” methods (your 2p model, I think). I plugged some project specific daily electricity data into the MVR example (multi variate regression)
and it seemed to give decent CVRMSE (~2-3%) but low R2 (~0.7). However, it appeared to provide some insight on cooling usage (monthly 2p models are meaningless for this in the UK’s temperate climate).<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>I also made some 2p monthly models of gas. I thought these were good until I compared successive years.
<b>I guess this is were understanding a range of statistical indices is helpful.</b><u></u><u></u></p>
<p> <u></u><u></u></p>
<p>Here’s the final rub, because the underlying data has so many inconsistencies that can only be made sense of with some regression models, it’s easier to “calibrate” the simulation model to the regression models than the original data.
But I may use 2p monthly for gas, daily MVR for electric…<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>So I need to ask if I have wondered completely off-piste with this!<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>Chris<u></u><u></u></p>
<p> <u></u><u></u></p>
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<div style="border-style:solid none none;border-top-width:1pt;padding:3pt 0in 0in;border-top-color:rgb(225,225,225)">
<p><b>From:</b> David Eldridge <<a href="mailto:dancingdavide@hotmail.com" target="_blank">dancingdavide@hotmail.com</a>>
<br>
<b>Sent:</b> Tuesday, March 14, 2023 12:53 PM<br>
<b>To:</b> Jim Dirkes <<a href="mailto:jvdirkes2@protonmail.com" target="_blank">jvdirkes2@protonmail.com</a>><br>
<b>Cc:</b> <a href="mailto:chris.malcolm.yates@gmail.com" target="_blank">
chris.malcolm.yates@gmail.com</a>; <a href="mailto:bldg-sim@onebuilding.org" target="_blank">
bldg-sim@onebuilding.org</a><br>
<b>Subject:</b> Re: [Bldg-sim] Lies, darn lies, and statistics<u></u><u></u></p>
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</div>
<p> <u></u><u></u></p>
<p>Indirectly there probably isn’t a daily set of metrics in the Guideline since the simulation programs aren’t usually outputting daily results, but there’s no reason there couldn’t be one statistically.
<u></u><u></u></p>
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<p> <u></u><u></u></p>
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<p>You could make one if you had only daily utility data and had to aggregate the simulation results to daily totals, there isn’t a published target metric but you could still show that you calculated one and why you think it was a good
or bad result.<u></u><u></u></p>
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<p> <u></u><u></u></p>
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<p>DSE Mobile<u></u><u></u></p>
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<p style="margin-bottom:12pt"><u></u> <u></u></p>
<blockquote style="margin-top:5pt;margin-bottom:5pt">
<p style="margin-bottom:12pt">On Mar 14, 2023, at 6:10 AM, Jim Dirkes via Bldg-sim <<a href="mailto:bldg-sim@lists.onebuilding.org" target="_blank">bldg-sim@lists.onebuilding.org</a>> wrote:<u></u><u></u></p>
</blockquote>
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<blockquote style="margin-top:5pt;margin-bottom:5pt">
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<p> <u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">Dear Chris,</span><u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">Kudos for appreciating a gap in your understanding. (I'm in your camp)</span><u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"> </span><u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">On the other hand, there are SO many variables in building operation that, short of a highly instrumented (and carefully calibrated) building for everything from lights to people
to plug loads to HVAC - calibration is a fiction (and I'm confident that no such building exists). Daily calibration is a complete fiction, perhaps even a deception. On top of that, a "calibrated" model is just a moment in time; everything going forward is
guaranteed to be different than during the calibration time period.</span><u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"> </span><u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif">I think of "calibration" as more like a sensitivity analysis - determine which variables matter more and which matter less. GenOpt works nicely for that purpose <a href="https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Flbl-srg%2FGenOpt&data=05%7C01%7Cjhaberl%40tamu.edu%7C1b9e306823164bc0353308db24eb12ef%7C68f381e346da47b9ba576f322b8f0da1%7C1%7C0%7C638144364315435766%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=r5pzooBP7ILTcRngSXCtJT7IRkOKdgaBTz%2BlyxeZsaU%3D&reserved=0" style="font-family:Arial,sans-serif" target="_blank">https://github.com/lbl-srg/GenOpt</a></span><u></u><u></u></p>
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<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"> </span><u></u><u></u></p>
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<p style="margin-bottom:6pt"><span><span style="font-size:10.5pt;font-family:Arial,sans-serif;background-color:white;color:rgb(34,34,34)">Jim Dirkes
<a href="https://urldefense.com/v3/__https://www.google.com/maps/search/1631*Acacia*Drive*NW*Grand*Rapids,*MI*49504?entry=gmail&source=g__;KysrKysrKw!!KwNVnqRv!Gyy3l3XXdU0uo6SKEX1uDKDVeqKvb3BM7ELdcAhCyGrNAZnPW1FVt64gzSX8gd4XJkQtPfaNE_z8YgDv9YFrSf_crIA$" style="font-family:Arial,sans-serif" target="_blank">
1631 Acacia Drive NW Grand Rapids, MI 49504</a> - 616 450 8653</span></span><u></u><u></u></p>
<div>
<p><span><b><span style="font-size:10.5pt;font-family:Arial,sans-serif;background-color:white;color:rgb(34,34,34)">Coffee Conversation:</span></b></span><u></u><u></u></p>
</div>
<div>
<p><span><span style="background-color:white;color:black">The "individual" is an impossible concept, conceived by the Enlightenment philosophers. It makes no sense to the Christian. In marriages, and families, in associations and friendships
and religious orders, we are not individuals, but a communion of persons.</span></span><u></u><u></u></p>
</div>
</div>
</div>
<div>
<p><span style="font-size:10.5pt;font-family:Arial,sans-serif"> </span><u></u><u></u></p>
</div>
<div>
<p style="margin-bottom:12pt">------- Original Message -------<br>
On Tuesday, March 14th, 2023 at 6:52 AM, Chris Yates via Bldg-sim <<a href="mailto:bldg-sim@lists.onebuilding.org" target="_blank">bldg-sim@lists.onebuilding.org</a>> wrote:<br>
<br>
<u></u><u></u></p>
<blockquote style="margin-top:5pt;margin-bottom:5pt">
<div>
<p>Hi All<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>I do find ASHRAE Guideline 14 a little too hardcore for my basic understanding of statistics. I can plug any of the equations into Excel, but I’ve realised my statistics understanding is very limited! (I’m outed!)<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>We don’t actually have to work to G14 in the UK (probably good because my copy is a bit old). I finally realised I didn’t know enough after I’d been (lazily) using R2 in Excel on some monthly data. I thought that R2 > 0.9 was generally
ok… yeah, it wasn’t.<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>So, are there any easy to understand resources available?<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>I’ve been messing around with the IMT as well. It’s been fun going back to DOS
<span style="font-family:"Segoe UI Emoji",sans-serif">😊</span>. This got me into daily methods, which leads to my next question. Is there any reason why there isn’t a daily calibration option specified in G14?<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>Many thanks!<u></u><u></u></p>
<p> <u></u><u></u></p>
<p>Chris Yates<u></u><u></u></p>
<p> <u></u><u></u></p>
</div>
</blockquote>
<p> <u></u><u></u></p>
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</blockquote></div><br clear="all"><br><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><b>Massimiliano Manfren, Eng. Ph.D.</b><br><span>Webmail : <a href="mailto:massimiliano.manfren@gmail.com" target="_blank">massimiliano.manfren@gmail.com</a></span><br>University email : <a href="mailto:massimiliano.manfren@mail.polimi.it" target="_blank">M.Manfren@soton.ac.uk</a><br>Skype: massimiliano.manfren<br></div></div></div></div></div></div></div></div></div></div></div>