model

Hi, can anyone help me out with this question? Assume that the true data generating process (the true model) is: y = 20 −30(x + r) + 4w + ê. Suppose that we also know that E(ê|x) = E(ê|w) = E(ê|r) = 0, Cov(x, w) = 20, Cov(x, r) = Cov(w, r) = 0, Var(x) = 10, Var(w) = 8 and Var(r) = 6. What...

What is the best model to study in-person attitude change over time?

Hi, Soon I will be performing an experiment where I must grow 4 different plant species under 4 different stressors, each stressor containing 4 levels of 'severity' of the stressor or in other words a difference in concentration. Growth of the plants will be measured over 22 time points, but...

I am struggling with an exponential kind of function (it's stock market so not a function itself). It's the function of bitcoin basically. As you can see it's exponential-like increasing since 2011. Now I don't give this example for price prediction but for genuine interest...

Hi, I am new on this forum and completely new to stata. PROJECT FOR MONEY Nevertheless, I am supposed to prepare a small project about alcohol consumption (in a couple countries - any) based on a couple variables like sex, type of alcohol, country, tax, GDP, etc. The project should consist of...

Hello everyone, I am a stats-beginner and I need help to understand if it is possible to compare two datasets. I am currently looking at the Residential Energy Consumption Surveys (RECS) databases, specifically to the 2015 and 2009 surveys. There have been some major changes in the 2015 survey...

Hello all, I was hoping someone could help my understand where a certain value comes from in my data output (using SPSS). I have performed a hierarchical multiple linear regression and the used PROCESS to find that my model has 2 predictor variables which both go through the 1 mediator variable...

I did a hierarchical multiple linear regression in SPSS with three predictor variables. All the variables have high F-values and are highly significant at each step of the model, but the constant is not significant (0.079) in the last step. Should I disregard all the results just because of...

Hello! I'm new to statistics but I am getting really stuck with my data so I hope someone could help me to choose the best statistical test. I have some test (dummy) data. I have data from 64 different hospitals, for 5 different countries countries, over 5 different years. In all of the...

Hello there, Im new in the statistics world and i hope that you can help me. i have two groups of sample that are divided by one y (depended) variable y = binary, is a good employee or no then i have ten variables (x) divided into demografic variables and profile test. Example: age, emotion...

I am part of a team creating a model for paediatric hospitalised patients and would appreciate some help. We are looking to produce an accurate model for weight estimation, using input variables of gender, age and mid-upper arm circumference. This would be helpful as some children arrive in...

The aim is to predict the breakdown time of a machine as a percentage of scheduled hours for the next day. So my time series looks like this, Break_down_percentage = 7%, 8%, 10%, 6%, 12 % etc. There are 315 data points which can be used to test the different models. I used ets(), arima()...

Hello, please take into account this: I'm a beginner :) I need to assess which of the two following specifications of a model is more suitable and explain it. This is what I obtained running properly on R the tools I had: FORWARD STEPWISE SELECTION: LASSO REGRESSION: This shows the...

Hey everyone, I am making an R project, and I have computed the models using all the methods we've studied in the lectures (particularly Lasso and Forward stepwise selection). In the conclusion, I have to assess which is the most suitable specification model. Could you help me writing...

Hi Everyone, i am struggling with finding a good way to analyze a dataset. The design is this: I have 25(n) subjects, all of them are tested in an experiment under 9 conditions. I estimate an electrophysiological index (idx) in every condition for each subject. Now I want to ask whether the...

I have 2 multivariate models created in R concerning nutrition Model 1 = -11.5±1.68 + 0.56±0.562 Intake + 16.6±0.165 Potassium concentration Model 2 = 16.6±0.123 Potassium concentration Both of these have come from the same data set. My question is, is it right that the standard error...

Hi, I've taken math course's up to Calc III and Diff Eq, but never a statistics course. So I was hoping this forum could help me. I am working with 10+years of temperature data taken from several loggers throughout a cave system. The loggers record temperature every 30mins, which I have...

Hello! I have a basic stats question: I want to model a phenomenon, and estimate parameters. How many observations would I need, to be as accurate as possible? I think it might have something to do with the degrees of freedom, but I am not exactly sure how to use this information. From the...

Hello everyone. I need help with the citation model as explained in This article "Bibliometric tools applied to analytical articles: the example of gene transfer‐related research" The model is expressed as C=KY+S C=cumulative number of citation Y=article life K=citation rate (number of...

Hello I have RT-Accuracy data. I want to estimate the parameters of a drift diffusion model (Ratcliff, 1978). I am assuming that: v(t)=v(t-1) + v + e(0,s). meaning that at each giving time evidance is accumulated from a normal distribution with expected value v and noise s. I am very very new...