Community Profile

photo

Peng Li


Last seen: 11 days ago
143 total contributions since 2020

Peng Li's Badges

  • Revival Level 2
  • 3 Month Streak
  • Thankful Level 1
  • Knowledgeable Level 3
  • First Answer

View details...

Contributions in
View by

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...

2 months 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...

2 months ago | 0

Answered
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...

2 months ago | 0

Answered
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...

2 months ago | 0

Answered
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...

2 months ago | 1

Answered
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 ...

2 months ago | 0

Answered
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...

2 months ago | 0

Answered
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...

2 months ago | 0

| accepted

Answered
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, ...

2 months ago | 0

Answered
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...

3 months ago | 0

Answered
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...

3 months ago | 0

Answered
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...

3 months ago | 0

Answered
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...

3 months ago | 0

Answered
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...

3 months ago | 1

| accepted

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...

3 months ago | 0

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

3 months ago | 0

Answered
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...

3 months ago | 0

| accepted

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...

5 months ago | 1 answer | 0

1

answer

Answered
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...

5 months ago | 0

| accepted

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

5 months ago | 0

| accepted

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...

5 months ago | 1 answer | 0

1

answer

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

5 months ago | 1

| accepted

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...

5 months ago | 0

| accepted

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

5 months ago | 0

Answered
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...

5 months ago | 1

| accepted

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...

5 months ago | 0

Answered
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)...

5 months ago | 0

| accepted

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 ...

5 months ago | 1

Answered
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...

5 months ago | 0

Answered
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);

5 months ago | 0

Load more