Peng Li

Last seen: 4 månader ago

143 total contributions since 2020

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Answered
Linear mixed models not working
In your first equation with random effect, you see that the random effect estimate is 0. If you check your data, you will find o...

6 månader ago | 0

Answered
how to detemine this residual matrix ?
Interesting. This is an application of the detrended fluctuation analysis (DFA) to a 2D image. Based on what your screenshot sho...

7 månader ago | 0

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Finding RRI fluctuations (ECG) in 1s windows
Your question isn't quite clear. If you want to get fluctuations of subsequent points in a time series as you described above, y...

7 månader ago | 0

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Prevent colorbar label overlapping with subplots axis
You can specify the Position property of each Axes to the position you'd like it to be at, instead of using subplot. I found thi...

7 månader ago | 0

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How to add " significant star " (*) to errorbar plot ?
This can be added using text function. You simply fake it using text label. For example, text(x, y, '$\asterisk$', 'Interpretati...

7 månader ago | 1

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Logistic mixed-effect regression example
You could use fitglme now to fit mixed effect logistic regression models. You can specify the distribution as Binomial and this ...

7 månader ago | 0

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Mixed terms and fitlmematrix
For new versions of MATLAB, you can use fitlm, fitlme, fitglme which allows table input, and allows formulas. But if you use fi...

7 månader ago | 0

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Mixed effect linear regression model with multiple independent observations
Also found this old post related to LME. Below is my opion for future readers. My interpretation of the output: The CNR decrea...

7 månader ago | 0

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Mixed-effect regression with repeated measures
This is also an old post now. I guess what the author of this post meant to use subject as a random effect, not a fixed effect, ...

7 månader ago | 0

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How can I fit a linear mixed-effects model with only quadratic/second-order terms?
This is an old post now. Just for future readers, you can explicitly get rid of any items you don't want by minus it. For the qu...

7 månader ago | 0

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How to interpret FFT output signal?
Based on your code, your sampling frequency is 1/3 Hz. There is no way you can detect a component of 0.316 Hz using 1/3 Hz sampl...

7 månader ago | 0

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Which formula fits better for this Linear Mixed-Effects Model?
To understand your dataset, I still believe that descriptive statics can give you the broad general picture. In terms of statist...

7 månader ago | 0

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readtable with multiple date formats
A workaround for me I think is to just load that column in string format. After loading you can do some cleaning before you conv...

7 månader ago | 0

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Averaging subsets of a large dataset
You can load this datasheet to matlab using readtable. after that, you have a table variable that allows easier manipulation. T...

7 månader ago | 1

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Answered
Integrate kernel probability distribution function
https://www.mathworks.com/help/matlab/ref/trapz.html trapz is a function that deals with numerical integration. Check the above...

7 månader ago | 0

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LME and multiple comparisons
If I understand your question correctly, you were asking a post hoc comparison issue? coefTest method of LinearMixedModel object...

7 månader ago | 0

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I am looking for a function in R that can help me deal with the different structures of the variance-covariance matrix. And thank you in advance
are you looking for solutions in MATLAB or in R? This is the community for MATLAB. and get back to your question, fitlme or fit...

7 månader ago | 0

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Question

speed up renamecats/categorical multiple columns
I have a huge csv file of about 16GB which over 9k columns. Each column is initially filled with some codes (either integer or s...

10 månader ago | 1 answer | 0

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Extracting and plotting max/min values from timeseries
Better take advantage of table format and splitapply function. tbl = readtable('data.csv'); tbl.day = day(tbl.Date); tbl.h...

10 månader ago | 0

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Answered
What does the ' symbol mean?
transpose. https://www.mathworks.com/help/matlab/ref/transpose.html

10 månader ago | 0

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Question

datastore readsize and buffer chunk
I am working with a single csv file of over 10G size. I'm trying to use mapreduce to perform some analyses. The program works as...

10 månader ago | 1 answer | 0

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How can i get contour plot like this?
https://www.mathworks.com/help/matlab/ref/contourf.html This might be what you need.

10 månader ago | 1

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Answered
Can some one please tell me how to find the maximum amplitude frequency of the ecg signal? I have attached below my code. I keep getting maximum frequency at 0 Hz.
try Y = fft(ecgData - mean(ecgData), NFFT); It is expected that the DC contains most of the energy of the signal. You could e...

10 månader ago | 0

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Answered
Having trouble with legend
Try this %Line Colors strColor = {'-r','-g','-b'}; %Legend String strLegend = {'nSamples = 5','nSamples = 10','nSamples = 15...

10 månader ago | 0

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convert a double matrix in cell within a table
t = table([ones(1, 4); ones(1, 4)*2; ones(1, 4)*3]) t = 3×1 table Var1 ________________ 1...

10 månader ago | 1

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Answered
Finding average of a large csv file
why do you need a loop? you said you have ONE cvs file with 1 column and 301 rows? you just need to import the cvs file and do t...

10 månader ago | 0

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Indices of the values for which two conditions are true
tbl = table(abbrev(:), firstword(:), number(:)); [gp, outTbl] = findgroups(tbl(:, 1:2)); outTbl.sum = splitapply(@sum, tbl.(3)...

10 månader ago | 0

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Answered
Help with Linear Mixed effects model formulas
For statistical questions, the first thing we ask is what the hypothesis is. From your equation, I guess you'd like to examine ...

10 månader ago | 1

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How can i export data from an 'edit text box' in app designer to an excel file?
I assume that you have properties linked to each of these values. In the callback, you can create a structure or a table involv...

10 månader ago | 0

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Is There a Way to Execute splitapply Functionality on Subtables of Master Table?
you'd better do this way: splitapply(@(x) sum(x, 1), T{:, 2:3}, G);

10 månader ago | 0