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15 views

Analysing a rating question

In a survey done to find the characteristics consumers prefer while choosing a retail store. Respondents were given 9 options and to scale them from 1-10 one for the most preferred value. Now we ...
56 views

R predict with “prediction” option

I'm trying to match the prediction interval of the predict.lm() function in R using the formula found in this discussion : Obtaining a formula for prediction limits in a linear model I'm using a ...
62 views

Confidence interval on R-squared

I know that it is possible when you realize a multiple linear regression to calculate the confidence interval on the R-squared and on the adjusted R-squared. Does somebody know how to do it with R?
131 views

How to model the range of variables?

Consider a case where instead of observing actual variable values, we are observing variable range. The possible range-values could be enumerated (i.e. could be a fixed set of values, for e.g. fixed ...
133 views

Creating summary tables / graphics in R for categorical data [closed]

I am trying to summarise data from a household survey and as such most of my data is categorical (factor) data. I was looking to summarise it with plots of frequencies of responses to certain ...
44 views

How do I analyze these two sets of data

I am doing a research study on self efficacy and birth month (when children enter school, if they are oldest in class or youngest). I have each of the participants scores on their self efficacy scale ...
216 views

Should Likert scale measures be treated as interval, ratio, ordinal, or nominal? [duplicate]

Forgive me, I am forgetting my basic statistics.
28 views

Rpart confidence interval

Is there any way to compute 95% confidence intervals and prediction interval for the predicted value at each node? Thanks!!!
53 views

A stopping rule for permutation test

I perform a permutation test multiple times on different datasets, each time I am only concerned about significant $p$ values. To reduce computation time would it be correct to introduce this kind of ...
77 views

How to get the confidence interval around the variable importance generated by randomForest?

Using randomForest in R is it possible to get a variance or confidence interval around the importance of a variable (% difference in mean square error)? From the randomForest package ...
125 views

Confidence interval for difference between proportions

I'm wondering if someone could let me know if I have calculated the confidence interval for the difference between two proportions correctly. The sample size is 34, of which 19 are females and 15 are ...
55 views

Burns survival dataset - meaning of midpoint of set interval

I'm using the well-known USC Burns Survival dataset to explore logistic regression in R. The independent variable is burn area, and the outcome is binary survival (yes/no). In the documentation, ...
176 views

Spearman Rho or ANOVA when examining effect of ordinal IV on continuous DV?

I have an ordinal independent variable (<1hr, 1hr, 1-3hrs, 3-5hrs, >5hrs) and an interval dependent variable (test scores). Apparently I am expected to examine the relationship between the two by ...
189 views

MLE/Likelihood of lognormally distributed interval

I have a variable set of responses that are expressed as an interval such as the sample below. ...
134 views

Some clear range and interval definitions

What is your or an offical (please provide link to citation) definition of range AND interval _? Or perhaps put in another way: what is the major important difference between the two terms _? In my ...
42 views

generate an exact pivotal quantity for theta

Given a random sample $x_1,...,x_n$ from $f(x|\theta)=\frac{\theta}{(x+1)^{\theta+1}}$, $x\ge0$ How to generate an exact pivotal quantity for $\theta$?
173 views

How to analyse Self-Assessment Manikin data

I am trying to analyse data collected through the Self-Assessment Manikin (SAM), which uses three pictorial scales to assess the three dimensions of pleasure, arousal and dominance. Participants are ...
163 views

What do you call a measurement that's halfway between ordinal and interval?

Suppose you have a measurement $Y_i$. Now suppose that the differences between two measurements $\delta_{ij}=Y_i-Y_j$ are an ordinal measurement. From my understanding, $Y_i$ is more informative ...
167 views

Confidence Interval for a Percent Change

Good Morning, A mentor has asked me to calculate the 95% confidence interval surrounding a percent change. To help frame the question, I have calculated the incidence of a disease within the ...
2k views

Are all values within a 95% confidence interval equally likely?

I have found discordant information on the question: "If one constructs a 95% confidence interval (CI) of a difference in means or a difference in proportions, are all values within the CI equally ...
1k views

Which tests can I use to analyze dependent likert-type data?

In a survey, where students were presented various stimuli, after each stimulus they were asked to rate the following: Quality, on a five-point scale from "Excellent" to "Bad", let's say $Q$ ...
252 views

Is data on a 1 to 4 scale interval or ordinal?

I have data on 26 participants (13 from computing and remaining 13 from non computing) who have participated in my research. Each participant is treated with a lab module (Hands on Robotics Session). ...
208 views

Confidence interval for Poisson parameter

To calculate an upper confidence limit on a Poisson parameter, a $\chi^2$ distribution with probability $P$ and $${\rm degrees \ of \ freedom} = 2X + 2$$ can be used (Nelson, 1982. Applied Life Data ...
152 views

Interval estimation of $\sigma^2$ with the reliability of $95\%$

I got these values from the measurement by a telescope: 20.1, 20.2, 19.9, 20, 20.5, 20.5, 20, 19.8, 19.9, 20. I know that the actual distance is 20 km and the error of the measurement is not affected ...
5k views

How to transform ordinal data from questionnaire into proper interval data?

Are there any straightforward methods of transforming ordinal level data into interval level (just as there are for doing it the other way round)? And performable in Excel or SPSS? Having the data, ...
899 views

Is a 1-sided 90% prediction interval equivalent to a 2-sided 95% prediction interval?

I have located references that indicate that a 1-sided confidence band is equivalent to the 95% 2-sided confidence band on a linear regression. Does this equivalence hold true for prediction ...
178 views

How to dynamically calculate interval designations of data?

I am looking for an equation to calculate appropriate intervals to designate values as very low, low, medium, high, very high for dynamic data. for example if my dataset ranges from 0 to 100 very ...