I have 2 variables and when plotted on a scatter-graph (see below) they do not have a linear regression. I will be undertaking my analysis on Genstat, but currently I have no idea what analysis I should be completing. Is anyone able to help? Do I need to transform data and then perform a simple linear regression or is some other form of analysis better?

]]>

SPSS Analysis Question]]>

The mean weight of antarctic penguins found in a colony last year was 15.4 kg. In a sample of 35 penguins same time this year in the same colony the mean weight was 14.5kg. Assume the population standard deviation is 2.5kg. Find the 95% confidence interval for the population mean. Possible answers:

- (13.77, 14.53),
- (13.27, 15.43),
- (12.37, 14.35),
- (13.77, 15.43).

Homework Question]]>

I want to see if there is a difference in the frequency recorded in each of these categories over time for each newspaper, and to compare between newspapers.

The categories A, B, C etc. are not ordinal but on a scale, but A, B, C etc do refer to certain key words used to refer to animals, which I have tallied up and changed into (100%) percent frequencies for...

Chi square test to investigate further]]>

I’m testing a hypothesis that requires Tukey-like comparisons of the variances (or standard deviations) of multiple groups. I’ve already used Tukey to conduct pairwise comparisons of the

Tukey-like pairwise comparisons of variances]]>

I have just a quick question concerning partial correlation:

Does this picture mean that 45% of the variance in Y that cannot be explained by X2 or X3, can be

uniquely explained by X1?

Thank you for your time]]>

I want to see if there is a difference in the frequency recorded in each of these categories over time for each newspaper, and to compare between newspapers. I know I can use the Chi squared test for homogeneity, but I want to see in what direction the change takes place if there is a difference; I am interested to know if there is a shift from A to F over time...

R help]]>

Participant allocation in RCT study]]>

yi ~ beta1*xi + errori

> dat <- data.frame(y=c(10,20,30,40),x=c(1,2,5,8))

> m <- lm(y~x,data=dat)

summary(m) gives me this information

Residuals:

1 2 3 4

-3 3 1 -1

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 9.0000 2.7988 3.216 0.0846 .

x 4.0000 0.5774 6.928 0.0202 *

If I plug in the values above to calculate y1

y1 = 9 + 4*1 - 3

y1 = 10

however, the predict...

error term in linear regression]]>

I am facing some trouble with the data of my master thesis and so I am looking for more general advice on how to deal with this topic:

I am investigating between the % of family ownership in family firms and the acquisition stake (also in %). Therefore, I planned to use a Tobit model (two limits).

However, after finishing my data collection, I end up with a dataset that consists in 319 out of 396 cases of 100 % acquisitions. So only a minority of cases has some variance...

How to analyze extremly left-skewed data?]]>

I wanted to do regression and it would follow Model Gravity for Trade theory. In the theory, there should be one country as a base so you could predict its trade flow in the future. I figure since it's a panel data, i can't create a column containing this country data since it would mess with other countries data. How could i do this? Should I separate this country data in a new...

Panel Data Regression in R]]>

I did a statistics exam and recieved a pretty bad grade corresponding to an E (I'm a political science student, and I've done many quantitative papers so I wouldn't think I'm completely lost usually). The exam was to conduct a factor analysis to find out whether Schwartz's Human values inventory, consisting of two theoretical factors, can be replicated in Sweden. I was handed a dataset with a 10-variable battery of Schwartz's values. I was also handed an article which found three factors...

Confirmatory or explorative factor analysis?]]>

Stanford Notes on Coronavirus

The new Coronavirus may not show sign of infection for many days.

How can you know if you are infected? By the time you have fever and/or cough and go to the hospital, the lung is usually 50% fibrosis.

Taiwan experts provide a simple self-check that we can do every morning: Take a deep breath and hold it for more than 10 seconds. If you do this successfully without coughing, without discomfort, stiffness or tightness, there...

Corona hints]]>

I...

ARIMA models]]>

Multivariate regression versus multivariable regression]]>

I want to measure differences between two groups who answered similar questions based on similar pictures of food.

Each group were shown 8 pictures of food in its packaging, but one of the groups were exposed to the pictures of the 8 food products where the protein content of the product had been photoshopped onto the packaging as a label. A radomization variable was used to ensure, that only half of the participants saw the 8 food pictures with protein labels and the other group saw...

Comparing similar variables for two groups who answered the variables based on similar pictures with small changes]]>

I would like to know what statistical tests are used to make sure the data is good.

Statistical tests that I am aware of are used to compare data sets. For these engineering tests, there are no data sets to compare. You do the test, average the break strength, and that's it. However, sometimes the data is all over the place and the...

Statistically Significant Data for Test Engineer]]>

We've got an experiment which involved temperature monitoring of 12 chickens. Sampling rate of the temperature sensor was 25Hz.

Chickens were divided into 4 groups, 3 chickens per group. We tested 4 stressors A,B,C,D in each group on 4 consecutive testing days, but always in a different fashion. The data I will be working with is the normalized temperature data 1h prior and 1h post stressor induction.

The protocol was a fourth order latin square design:

Group 1 received A,B,C,D on 4...

Compare continuous temperature data across 4 different groups]]>

sorry just a bit confused as to whether the data from the Continuous Plankton Recorder is discrete or continuous?]]>

I need to download data in a predefined SPSS format from a website. However, when the data is loaded in SPSS periods are used instead of commas before the decimals. How can I change these periods into comma's in SPSS?

Best,

Eva]]>

I would like to ask you for little help

I have 4 types/gropus of artificial lenses (named: BY, Softec, ZA, ZCB). In each type there was done calculation using a 3 different formulas (1,2,3). I have 30 subjects in each lens type.

I would like to compare means between ZCB and other lenses for each formula....

Example:

1. ZCB_Formula 1 vs BY__Formula 1

2. ZCB_Formula 1 vs Softec_Formula 1

3. ZCB_Formula 1 vs ZA_Formula 1

.

.

Than same for formula 2 and 3

I have done t test for each...

Is bonferroni correction necessary ?]]>

I´m using AMOS to anlyze mean differences between two different groups. I used (Byrne, 2010, Structural Equation Modeling with AMOS) as basic literature and followed the steps. I aded two groups and grouping variables, then I defined a model for both groups and used the multi-group-analysis button. This worked perfectly well. However, the second part (comparing groups) of the analysis did not work. To calculate the differences, one group has to be fixed as zero, whereas the...

testing for equivalence of latent mean structures in amos]]>

y = b + mx + error

I need to obtain the

The error is of Gaussian distribution with mean 0.

Anyone who knows how to do that?]]>

I'm doing a validation of a questionnaire for my thesis and I should investigate the validity of my test with others one. To do so I've been asked to calculate the correlation between two scale sand I'm a little confused on how to do it. I thought to use the pearson correlation but I've always used it between two variable (e.g, anxiety and time spent studying) so I've no idea how to do it between my scales since one has 37 item and the other 6, plus one is a likert scale and the...

Correlation between questionnaire to test validity]]>

- Your space ship is not very well managed (the captain is an alcoholic) which means that a lot of people are late for their work shifts. The captain has made an announcement that he has set a goal for everyone to be on time for at last 80% of the shifts. In one day there are 35 people working shifts, and you notice that 23 of them are on time. What is the probability of having 23 of 35 people on time if the true underlying rate was 80%?

A. 2.02% B. 2.43% C. 3.44%. D...

Please help!- Probability question]]>

I have an unreplicated factorial design (2 x 2 x 2) and did the following data analysis.

Main effects

Interaction Plots

Normal Plot

Half-normal plot

Lenth Plot

Will a contour/surface plot be appropriate for this design? What other kinds of data analysis can I use?]]>

First of all, I would like to apologize for the question I'm gonna ask regarding the fact, that I am absolute beginner in statistics.

Currently I'm trying to test some hypotheses in Rstudio using Simple Linear Regression, as I am aware that before interpreting results of my model I have to provide verification of assumptions that should be meet within the model.

Unfortunately, one of the key assumption is not very clear for me, could someone explain please?

Mean of the residuals in Simple Linear Regression *Beginner Alert*]]>

I am currently doing my dissertation and I was a bit over ambitious not knowing fully what I had gotten myself into when beginning my research. I have been recommended by my advisor to use JASP software to undergo SEM, however, it is a lot to get my head around, and not even my advisor really understands it. I have been trying for ages to work out how to do it but would really appreciate the help from someone who has used JASP software to do this before. Alternatively, could anyone...

SEM on JASP to measure TPB variables]]>

Anyone with Idea on how top plot Reverse distribution plot in Stata? code will be of help.

Thanks,

P]]>

In a two-arm clinical trial with approximately 100 participants per arm and remission rates around 50% (RR significantly different both in a direct comparison and 95% CI crossing a pre-defined non-inferiority limit) I have compared the risk of relapsing depending on the treatment received. The risk is very similar irrespective of treatment group.

Comparing those that do relapse within a three-month period (group 1: 19/43; Group 2: 25/55) participants in the first treatment arm have...

Kapler-Meier survival analysis or a simple t-test? Orthodoxy necessary?]]>

This might be a kind of basic question in confounding in logistic regression, but would still appreciate some help.

I coded (in SAS) a logistic regression model were my predictor (religiosity) is known to be a protective factor of the outcome (substance use).

As expected, the odds ratios show that the more religious you are the less your risk of substance use. I am now running a similiar model adjusting for potential confounders. not having a psychiatric disorder is also a protective...

Confounders]]>

I hope everyone is doing well. I have the mean scores of the dependent variables. I want to see whether their order is sgnificant. What statistical test to use? Attached is a file with the data.]]>

I am confused to know what test to be used in scenarios such as below. Below dataset can be checked on this link also (http://users.stat.ufl.edu/~winner/data/pricequal.dat)

I want to check if the higher price of the beer is justified as per the ratings provided (number of observations)

I thought of using spearman's rank correlation first, but then realised that it is not applicable as it will not be making use of observations column.

price, rating , observations

3 0 4...

Which test to use to understand if higher priced version of the beer is worthy of higher rating?]]>

Help with test]]>

I'm currently doing my masters thesis about blood pressure monitors.

I'm compairing them on repeatability using a simulator.

Now i have 5 different devices with each 3 simulations x 85 measurements. (Simulations are High blood pressure, low and normal)

I did the basic thing like look at the mean values and standard deviations but want to go further.

What I already tried to do:

T-test;

I used excel to calculate this but the really really small;

...

What analysis is best for my research]]>

I have two samples from two independent communities that have mean and standard deviation of time attribute on them, but I do not have access to the amount of time each participant in each sample so I cannot verify the normality of the data distribution. That is, for example, I know the mean and standard deviation of the time attribute for 20 participants are 10 and 1.5 respectively, but I do not know what the time attribute value was for each of the 10 participants, so I cannot...

Select the appropriate statistical test without knowing how the data is distributed, normal distribution or not]]>

I was recently asked this in an interview but was not sure how to answer. I tried saying that it would depend on time, the readiness of the samples, and the cost of the tests but the interviewer said to ignore those factors. I said there should be enough samples to make have a statistically significant outcome. So I guessed 100 samples. The interviewer seemed happy with the answer but wanted to know the...

Mechanical Engineering Sample Test Size]]>

I have a rather unique question that I'm having a hard time getting my head around and how best to approach - any help at all would be greatly appreciated!

Let's suppose I have a test, with a binary outcome, that is dependent on how much of a chemical is present. With a little bit of this chemical present, the test has a high probability of succeeding. With more chemical present, that probability goes down. These probabilities for various concentrations have been mathematically...

Binomial Distributions for Testing Chemical Concentrations]]>

Another concern, there are a lot more satisfied than dissatisfied people, I have never read that this is an issue with correlations, but I figured I ask.]]>

A construction company in Naples, Florida, is struggling to sell condominiums. In order to attract buyers, the company has made numerous price reductions and better financing offers. Although condominiums were once listed for $300,000, the company believes...

Please help - probability question]]>

I am trying to interpret some data, where an ANOVA has found significant differences, and then a post hoc Student-Newman-Keuls was run. The output is attached. My question is as follows. Do I have it correct that the two columns as they are mean that the SNK test found significant differences between GNV and RR, but was not able to find differences between RR and CR, and also between CR and GNV? Also, I'm confused what the Sig. row means, the last row in the graph. I note that...

Help needed interpreting SNK post hoc test]]>

I have a multiple regression with 200 binary independent variables. The dependent variable is not binary. I know that there should not be more than 10-20 independent variables in a multiple regression. However, only 6 of them take the value 1 and the rest take the value 0, i.e. that only 6 of the independent variables have a value.

Is it possible to run a regression with 200 indepent variables or should I run a simple linear regression for each independent variable?

I am looking...

Regression with binary independent variables]]>

I have a question about the difference in results between the Shapiro Wilk test and the calculation of a Z score with skweness and kurtosis (divided by SE).

I have a sample size of N = 143. It is divided into two groups (Western candidates N = 71 and non-Western candidates N = 72). To assess the normality, I did the following:

Calculate a z-score by dividing the values for skewness and kurtosis by their respective standard errors (SE).

If I use this calculation, I only have 1...

HELP! T-test, normality assumption. Great difference between Shapiro Wilk and Q-Qplot/ Z-score calculation]]>

Thanks!]]>