Is the logarithmic transformation a necessary step in time series analysis ?

Hello, I'm checking if the log-tranformation of time series data is a necessary step; We all know the aim of such transformation, but in every study (in time series analysis) we found the authors...

15 February 2021 5,655 14 View

Is the test of the H1 hypothesis in mediation analysis total effect or direct effect?

There are three hypotheses and I carry out direct effect and indirect effects with SEM. H1: There is a significant positive relationship between A and B. H2: There is a significant positive...

08 February 2021 9,141 3 View

How do I convert or prepare a taxi dataset to a time series with the fixed intervals?

I have NYC taxi trips dataset contains multiple attributes like (pickups and dropoffs) coordinates, DateTime also, trip distance and so on, indexed by "tpep_pickup_datetime" coulmn as...

01 June 2020 4,164 4 View

Logistic regression, Linear Regression and Survival models are they complementary methods ?

Hello dear professors and colleagues, I have a data set where I want to applied three methods: Logistic regression , linear regression and survival models, of couse each method focalise on an...

09 May 2020 3,746 7 View

Could the relationship between social media use and 'cocooning at home' be investigated in the Covid 19 process?

Dear academics, I want to do a quantitative research on the use of social media in the process of closing the house in Covid 19 process. At this point, 'cocooning', that is, maintaining a...

24 March 2020 3,879 3 View

Is there any pH buffering system or device for acidic microbiological experiments?

Dear researchers, I am working on acidophilic bacteria and mineral interactions. I will use rock grains in my microbiological flasks and see the effects of bacteria to dissolution of rocks....

18 March 2020 191 4 View

The standard error in the standardized model results section in Mplus7 does not show the standardized error, t value and p-value?

I'm doing bootstrap 2000 for multiple mediated analysis on Mplus7. However, in the standardized model results section,does not show the standardized error, t value (EST./S.E.) and p-value. How...

17 March 2020 9,102 3 View

What would be the effects of coronavirus on publication process and times reviewing of articles?

Hello dear Reserachers, Professors, I'm asking myself and you, for the effects of Covid-19 on publication, reviewing process, and reclassification of priorioties on certain topics; e.g: and with...

15 March 2020 8,598 5 View

Which models are best suited for time-series (multiple variables) data-set analysis?

I have a data-set with multiple variables. I would like to do a statistical analysis to determine the extent of the impact of factors on the change in time, Which models are best suited for...

28 July 2019 2,329 4 View

Agilent 6460 Tuning problem?

It tunes perfectly in Negative mode; and in positive it doesn't see the high masses and subsequently fails. Any ideas?

04 May 2019 8,450 3 View

error in running a model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

error in modelling model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

MGL tools

20 June 2021 0 0 View

i have some problem with chtMultiRegionSimpleFoam

--> FOAM FATAL ERROR: Maximum number of iterations exceeded From function Foam::scalar Foam::species::thermo::T(Foam::scalar, Foam::scalar, Foam::scalar, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar) const) const [with Thermo = Foam::hConstThermo >; Type = Foam::sensibleEnthalpy; Foam::scalar = double; Foam::species::thermo = Foam::species::thermo >, Foam::sensibleEnthalpy>] in file /home/ubuntu/OpenFOAM/OpenFOAM-4.1/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 66. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::calculate() at ??:? #3 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::correct() at ??:? #4 ? at ??:? #5 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #6 ? at ??:?

24 March 2021 0 0 View

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10?

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10? Since, the growth curve from day 2 to 10 won't be like the "Logistic curve" it might not follow logistic...

03 March 2021 1,401 3 View

What is the production process of CaFe ferroalloys?

I looking for ferro calcium production process

03 March 2021 1,755 4 View

Resistor definition in Piezoelectric bimorph with ANSYS workbench

Hello, good day! I am trying to simulate similar bimorph piezoelectric harvester with below commands. However, the output power doesn't change with resistor value. Please help to find the reason. ET,10,CIRCU94,0 !SET UP RESISTOR R,1,100000 !RESISTANCE VALUE TYPE,10 !SET ELEMENT TYPE E,1,2 !CREATE RESISTOR BETWEEN NODES 1 AND 2 Thanks in advance Regards,

02 March 2021 0 0 View

Do you know any MR image dataset?

I would like to research on MR images (0.5T and 3T). Can you please suggest some websites that I can download dataset including both 0.5T and 3T MR images? Thank you.

02 March 2021 7,735 3 View

Which is suitable for use with Python? MySQL or SQL Server?

Which is suitable for use with Python? MySQL or SQL Server? What is your suggestion?

01 March 2021 3,422 3 View

How to Eliminate cosine error and abbe error in LASER measurement system(for example Rhenishaw XL80)?

I like to do project in laser measurement system. My objective is to eliminate or reduce the cosine error, abbe error in Laser measurement system. I have Rhenishaw XL80 system. Please tell the...

28 February 2021 4,890 3 View