I am working on a project where I have three theoretical constructs and have binary coding for positives and negatives of each (attached is a snapshot of my data, but total N=159 and age ranges from 5-19). Couple questions:

1. How can I test this data for normality? To know if I should use parametric or non-parametric tests?

2. What test should I use to compare each construct (columns E-J) across age, gender, and location? And on whether or not they know a scientists (last column)...

Normality and tests]]>

I plan to find this out using mostly likert scale questions in my survey.

However, I am wondering what statistical analysis I would use to analyse the data I...

What statistics test should I use?]]>

For example, suppose an instrument has a documented SD of...

Relationship of precision of mean of repeated measurements and precision of single measurement]]>

In other words, If I have correctly understood, if n is sufficiently large (there are various conventions in this sense, for example,

Central limit theorem and sampling distribution - Doubts]]>

Johnson Electronics makes calculators. Consumer satisfaction is one of the top priorities of the company's management. The company guarantees the refund of money or a replacement for any calculator that malfunctions within two years from the data of purchase. It...

Finding Standard Deviation]]>

Assume that the precision of the measurements is fixed and independent – each measurement has the same...

How to calculate the precision of the mean of univariate time series data, based on the precision of the discrete measurements it consists of]]>

Suppose a traditional medical test says that the probability of a random sample of patients being positive to disease Y is 5%, but we know that the test is not accurate when identifying the positive cases. My assumption is that the real probability might be closer to 30% among the...

Using Bayesian statistics to improve classification task]]>

I’m a high school social studies teacher and I was wondering how I can analyze my students’ engagement level with the online platform where students do various homework/assignments (readings, discussion, quiz, etc.…). I’m using Canvas and I can see the variables including the number of pages students view, actions (writing on discussion board, submitting quiz and so on), grade distribution, on-time/late/missing submission. Can anyone help me to design a simple model to research...

What kind of test should I use?]]>

I have a set of values which are a time series and follow a decreasing exponential distribution.

I would like to understand what the best method might be to predict the next value in the series.

Do the options include

1. Transforming the variable to try and get normality.

2. Creating an autoregressive model of some nature

thanks

Scott]]>

I have a question in Conditional Probability and I would appreciate if you could help me solve it.

I have the probability of of the Hourly temperature of the day. if my temperature varies from -3,-2,-1,0.....+9 and I know the probability for each temp. every hour through the day (for example that probability that the temp is +1°C at 12:00 am is 13% and at 01:00 am is 15% and so on for 24 hours.

How could I know the probability that the hourly temp. will be:

a) the same for...

Conditional Probability of several events]]>

I need your guidance about the analysis, as you are good at statistics.

I explain my experimental design.

Actually I inoculated 3 microorganisms (ASS-ASL and ASY using different concentrations i.e. 50-75 and 100ul/L). I wanted to check if these organisms at different concentrations affect the growth of wheat seedlings. I had 4 replicates for each treatment and 4 CK control for each treatment (No inoculation of microgranisms). As I am not clear, I can send you my raw data...

Statistical analysis in agriculture and agronomy]]>

-2Deviations = Mean / 6.5]]>

I'm trying to calculate an estimate, for each decade between 1800 and 2019, of the number of German-descent population in North America (Canada and the U.S.). I came up with something of a methodology to do that, based on some facts from 1790: that Germans made up 8,7% of the white population of the United States, that the white population of the U.S. numbered 3,172,006...

Problems with estimating the growth of a population.]]>

I am trying to see the effect of income level towards fraud behavior. So in the so-called population, I have counts for each of the bad/good/new users:

BAD: 260

GOOD: 480

NEW:50

I also have a group of high-income users with these counts:

BAD: 50

GOOD: 95

NEW: 8

I am trying to see whether high income affects user fraudulent behavior. Can I use Chi-Square Goodness of...

Using Chi Square Test to check the effect of a variable?]]>

Would be thankful for every comment or idea.

So i think: HHHHHHHHHHHHH 13x heads or 12x H 1x T HHHHHHHTHHHHH wont be the most frequent...

13x times coin toss (most frequent sequence)]]>

I'm currently doing a marketing research project at university. It requires me to create a survey on Qualtrics and to then collect and analyze the data with SPSS. The project also

I. Chi square test for independence

II. Analysis of variance (ANOVA)

Now, I have divided the variable of "age" into three categories 20 years and below, 21-29 years, and 30 years and above. I want to determine the whether the...

Marketing research project - ANOVA or Chi Square test?]]>

Also are there circumstances where one would round up a decimal<5 and round down a <4. Any round off examples? Thanks.]]>

I am very confused about how to select the appropriate statistical method (parametric or not) by considering N number in the dataset. Some references say that if the N number is below 30, parametric tests cannot be used but some others say that it is not necessary to reach 30 subjects to perform a parametric test as long as the dataset shows a normal distribution.

Can you please provide simple explanations and/or suggest some references that supports both points of view?

Any help will...

N>30, or not! This is the question!]]>

What I want to figure out is if there is a significant difference in the prescription rates of medicine 1 between males and females.

Which statistical method should I use to test the difference? (I use SPSS)

Any helps will be pretty much appreciated.

P.S.: The dataset...

Probably A Very Simple Question (but I am not able to figure it out)]]>

Help with Combining Variables]]>

I'm doing an analysis on a set of data with a dichotomous independent variable (drug or placebo) and a dichotomous dependent variable (sick or not sick). Would you run a logistic regression analysis?

Thank you in advance!]]>

I am doing an econometrics course where I am to do a regression analysis on some firm data.

I want to analyze some shipping data of frozen goods to predict the temperature of the shipped goods at their end destination.

My problem is that I am unsure which kind of analysis to make when I am interested in both time-variant and in-variant variables

My data:

I have approx 100 data points for different shipments. For each data point, I have the starting temperature of the products (same for...

Choice of model/strategy for multiple regression analisys]]>

I understand chi square tests of independence, and have read the FAQ on chi square tests. What confuses me somewhat is the use of chi square in some instances.

I have always understood a chi square test of independence as being a test of an

And I have always understood...

Chi square test of independence - test of difference or association?]]>

When I see this done with an intercept only model I notice the examples are taking the parameter and reversing the sign in generating the following formula to generate predicted probability.

pp = e to the parameter value [they actually use the negative parameter so if its .2 they use e to the negative .2 power]/1+ e to the negative parameter value.

Not sure if I am getting this right.]]>

Interpreting logistic regression]]>

I have arrived at some results through brute force but would like to understand or incorporate some formulas if possible.

If you are not in the San Jose, CA area, I can set-up WebEx meetings. If you are, in person would be great.

If you are interested, please contact me by email at sjelso@yahoo.com and let me know your rate.

Cheers...]]>

I am new to the forum, greetings to everybody and thank you in advance for your help!

I have a question about how to approach an ecological dataset:

I have data on the number of animal species visiting sites.

I also have data on the total consumption of a common prey item.

Now, I would like to indirectly estimate the importance of each species on total consumption.

I would like to know whether lions, tigers, or leopards are driving consumption, or if they have a similar...

Disentangling effect of different players]]>

Code:

```
#FOR BEEF#
Food_3$Beef = (((((((Food_3$IM_Weekly_serving_2
*...
```

" As with other forms of regression models, the analysis of multilevel data should incorporate the centering of predictor variables to yield the correct interpretation of intercept values and predictors of interest (Enders & Tofighi, 2007; Hofmann & Gavin, 1998).Predictor variables can be group-mean or grand-mean centered, depending on the...

Centering predictors]]>

I am currently performing model analysis on a linear mixed model (4 fixed and 1 random effect) and observed a strong linear correlation in the residual plot (see below). Does anyone have any suggestions on how to adapt the model (transforming variables/introducing link functions etc.)? Also I don't really understand how this can happen...

Really appreciate your help!

Best,

Jan]]>

It would help if you can not readily do multilevel modeling with a 4 point DV to know what can analyze this. I am testing the result of area on satisfaction.]]>

I would like to know if the method I’m using to calculate a probability based on an occurrence rate is correct or if there is a better method to use.

Probability given an occurrence rate (small airplane fatal accidents)]]>

- The New England Patriots are playing the Buffalo Bills.
- The fractional odds are Patriots 1/2 and the Bills 2/1, where a bet on the Patriots risks $2 to win $1, and a bet on the Bills risks $1 to win $2.
- A rational bettor has $1 to bet.
- A $1 wager on the favorite Patriots yields a $0.50 profit, if they win.
- Or, a $1 wager on the underdog Bills yields a $2.00 profit, if they win.
- Therefore, the relative payout on the Bills is 4X that of the Patriots (2.00/0.50; this...

Nonlinear odds-to-probs conversion]]>

48 genotypes were subjected to 4 temperature treatments. In each treatment, there were 3 replicates per genotype, which amounted to 144 subjects per treatment and a grand total of 576 subjects in the experiment. Within each treatment, subjects were randomly assigned to experimental Units (24 subjects could fit into each Unit, so there were 6 Units per Treatment, totaling 24 Units in the experiment).

I am...

Hierarchical anova: how to calculate degrees of freedom]]>

I have been given a question in answering which, using SAS, I have to calculate the variance in the dependent variable that is accounted for by four independent variables "jointly", "separately, without the presence of the other independent variables" and "separately WITH the presence of other independent variables".

I have a little bit of a hard time distinguishing between these three, esp. the last two. Also, I want to calculate that using SAS.

Thanks in advance]]>

I am using the software https://www.socscistatistics.com/tests/studentttest/default2.aspx

(1) Please help to know if I should select one-tailed or two-tailed?

(2) For 1 variable...

Independent t - test]]>

I took a screenshot of the question with the right answer. Can anyone help me to figure out why does a 3D plot can be generated only from 4 or 6 conditions?]]>

as far as my understanding is so far I would need to run both a one way anova (between group) and a repeated measures one , is this correct or is...

one way anova]]>

I am a first timer, please I need help on Research topics for Masters, preferably in pannel data analysis, or comparisons of artificial nueral network and regression analyses.]]>

I performed a 2X3 ANOVA and got an ordinal interaction. One variable was pre/post treatment and the other was type of measurement.

The thing is, all p's are significant (p<0.001). So, how can I tell if there are differences in the significant differences?

That is, all measurements increased from pre to post. But how can I tell if one increase was significantly greater than other increases?

I also performed a 2X5 ANOVA and I have the same problem there.

I'm using SPSS]]>

A - I have a set of google trends chart data and I create a line chart from that data in google sheets.

B - I also have google trends chart data for the search query of "Google". This shows me the peak hours that people query Google.

These 2 datasets shows smilarities. Actually the search term (A) is mostly used when people are more...

Trying to normalize peak hours]]>

After Missing value analysis and Multiple Imputation I want to check the complete data.

According to literature and other studies I found the need to create Kernel density plots between the observed and new datasets and also check for posterior replicates of the completed data

How can this be done in SPSS? Please let me know if you have other thoughts how to check my data on SPSS

Thank you]]>

For a "meta-analysis" i would like to sum up the result from 6 studies. Still values stated in these studies are median (IQR), mean (SD), mean (range), mean (95% CI). Do I have a chance to calculate a mean +/-SD based on these values?

Thank you for your help in advance!

Kind regards,

Sebastian]]>

I'm doing some education research and would love some help! I'm guessing I need to learn about Z-statistics, but I'm just a beginner at stats....

We're looking at the scores of students across a country. The average score is 0. It's pretty much a normal distribution, will students doing less well having a negative score. Most scores range from -1 to +1, the standard deviation is -0.36.

I have a group of a particular kind of students, let's call them SS, who have an average mean...

How to compare two sample populations?]]>