Questions tagged [percentage]

Number or ratio expressed as a portion of 100

237 questions
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weighing percentage changes by number of samples

Applying one simple formula for percentage change. This: 100 * (8 - 2) / 2 = 300% gives the same results as this: ...
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Is my formula for percentage change wrong? [closed]

I know the normal formula for calculating percentage change is: ((y2 - y1) / y1) But I've been using the following forever and I never get a wrong answer: ...
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Calculating per cent improvement in test error

I’ve come across this statement regarding an improvement percentage and I don’t know if it’s okay. It says this: The training error and test error using the neighborhood model are 0.34 and 0.54 ...
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Using glmrob function in R with proportional/percentage dependent variable

I have performed a glmrob to infer whether belonging to one of the treatment groups causes a higher % in success. I have used the following code: ...
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How to determine the percentage difference between two quantities associated with uncertainty measure

Say I have two quantities 10 ± 2 and 12 ± 3 (uncertainty is standard error). How do I determine the percentage difference between them? Or should I determine it at all (There is no meaning to do it in ...
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Is there a signed (ie anti-symmetric) version of SMAPE?

The symmetric mean absolute percent error (SMAPE) is a symmetrized version of percent error with the formula: $$\frac{200\%}{n}\sum_i\frac{|x_i - y_i|}{|x_i| + |y_i|}$$ SMAPE is symmetric: ...
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which regression to use when response variable is in percentage [duplicate]

Hello I am working on a regression problem with a data set where my predictor variables are in the multiples of 10,000 however my response variable is in percentages. I tried to fit a linear ...
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Proper analysis procedure of paired rate comparisons - ratio or difference?

I have a set of population counts where each row represents a different region, and variables show overall counts and counts/percentages within specific groups/criteria. I am interested in the cross-...
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Two way ANOVA with percent change

I have two groups of animals: "active cycle" and "inactive cycle". Within each group, there are two groups: "control" and "treated". I measured the levels of a specific receptor for each animal in ...
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Comparing percentages with unequal sample sizes

I've spent some time collecting participation data on a schools competition. To sum it up: Roughly speaking 1000 schools take part in the initiative every year. Only 10 schools become finalists. ...
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How to interpret coefficient when the dependent variable is a percentage change?

I am having some trouble interpreting my regression output. My model is LN of transaction volume = alpha + $\beta_1$_RER + control variables RER is defined as the change in the average exchange rate ...
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How do I calculate relative proportion of a fraction with respect to total value?

I have several curves in one graph (see fig.). There are 5 discernible segments within each curve that are individual slopes. Within each "x-coordinate segment" there are five samples with their ...
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Appropriate analysis for univariate proportion data and environmental variables

I'm new to statistics so am trying to choose the best analysis to find if; There is a difference between canopy cover (0-100%) at different sites There is a relationship between canopy cover and ...
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percent change from baseline

i have a 10 samples with baseline and follow up scores. I need to calculate a percentage increase or decrease based on the scoring scale, in this case its 0-56, and the objective (whether the ...
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Statistic to measure no.of cancelled members

These percentages indicate how many male vs female members cancelled a subscription we offer. Male Female 22% 13% Looking at the ...
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How to create a scale combining normalized percentile scores to get an overall result

I am trying to work out a scale for assessing a person’s risk for a particular behavior (like rob a bank). The likelihood of this behavior occurring or not occurring will be based on scores for a ...
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How do I convert a survey scale [7-point, -3 to 3] to a 7-point scale [1-7]?

I am working with a survey scale that is from -3 to 3. I have a mean value of .94 and I want to identify if there are ceiling effects, but I need to change the entire scale to 1-7 in order to ...
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Interaction effects for independent variables in percentages

If the Independent variables are in percentages, then will it make sense to calculate interaction effects using the original figures? or do I need to make any changes?
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Regression equation using percentage values in R : Request your help for a beginner

Can percentage values be independant variables? Can I use then as it is, or do I need to take log. And also if I have to consider interaction effects when independent variables are percentages, how ...
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Comparing percentages based on likert scale by year

I'm reviewing an analysis someone else has done on some Likert scale data. They've assigned each point on the scale 1-5 (1 = bad, 2 = poor etc.), found the average score in each area, and then ...
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Modelling percentage and proportion data with GLM's [duplicate]

I would like a simple answer, if there is one, to a question I cannot seem to find on here. What is the best way to model percentages? Say I have a glass that is empty and I fill it with liquid ...
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Average percentages [duplicate]

Hi I am trying to average percentages but what each percentage represents is not equal. The 5 numbers are : 100%, 0%, 0%, 20%, 75% 100% represents 4 items 20% represents 10 items 75% ...
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Modelling a percentge as a dependent variable

I have a dataset containing 4 variables: Y - the dependent variable. This is a percentage of students in a school that choose to take an external exam. The values vary from 20% to 70%. X - the ...
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Is it reasonable to display “percentage data” in a boxplot, why?

I have data that are in fact percentages of C (bound to clay) combusted in a certain temperature interval. Exemplary data: ...
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What model should I use if I want to describe the relationship between the % and binary outcome

I want to model a relationship between the % of students who received a flu vaccine at a certain school and whether their school had a flu outbreak or not. Thanks
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What statistics test to compare the repartition of multiple choices between two groups?

I made an experiment about UX where the participant has to detect among five differents configurations the one that he prefers. The configurations are slightly different and are presented randomly 3 ...
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Comparing percentages from survey results with different response rate

I have to compare survey results based on a questionnaire floated. Out of total 50 questions, A responded for 40 questions. Out of 40 questions responded, answer for 30 questions are Yes. Out of ...
113 views

On average of percents

I have read some pages about how to calculate the average of percents. However, still I don't understand something... Assume data points are organized in the following manner: We have two categories ...
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regression with percentage DV and multiple dummy IV

I am running a market analysis about e-mail responses for my marketing class. I have the following data entries: Observations: 400 different sequences of e-mails where sent to different target ...
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How to standardize count data for different sampling site sizes

I want to do a linear regression for my data but I’m not sure what I need to do with my raw data before running a linear regression. I have counts for species in several forests of differing sizes. I ...
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Difference in Quantile and cumulative percentage

How would you differentiate between the quantile function and cumulative percentage below? Note the treatment of numerics as categorical when grouping is performed. When would you use one over the ...
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Interpretation of the phrase “percent reduction relative to”

In the book Freakonomics, the following phrases appear: "From 1960 to 1985, the number of police officers fell 50 percent relative to the number of crimes. I interpret the above to mean that  r_{...
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Regression with frequency rating in percent as dv

I seem to have a similar issue as asked in this thread, nevertheless I'm still clueless about what model I have to fit to my data. I conducted a repeated measure experiment (consisting of 2 sessions) ...
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T-test for “discrete” variable

In my dataset, I have 2 columns. Both of them are a percentage. However, they only take the following values : (0,10,20,30,40,50,60,70,80,90,100). I would like to know if I could do a t-test on those ...
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How to report percentage change in proportions?

I want to compare changes in the proportion of fruit purchases over time for a household. For example, in year 1, 4/40 (10%) fruit were apples, in year 2, 12/80 (15%) fruit were apples. When ...
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Interpretation of variable in a probit model

I am struggling interpreting the coefficient of a variable which is expressed as a proportion in a probit model. As it currently stands , I am interpreting the average partial effects of this variable ...
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Comparing percentiles of datasets of varying sizes

I am trying to build a simple anomaly detection solution. I have a dataset with normal observations. It has about a 100 values. I calculate the ...
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Statistical significance of percentage difference for a poll question with multiple options?

The question is: how to calculate the statistical significance of difference between percentages in the case described below? Suppose we have a poll question with $n$ answer options $A_1, …, A_n$, ...
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Should I use weights in calculating the Coefficient of Variation for transformed proportions?

I have percentages of people having an event for 21 regions. Since I want to calculate a Coefficient of Variation, I took the arcsine of the proportions to normalize data. The problem is: every region ...
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Ratio measure vs. difference measure?

I am comparing food inflation estimates from different sources for the same year and country. Food inflation can be negative or positive, e.g. year 2010: 5% in Source A and 7.5% in Source B; year 2011 ...
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How to create a model in which one predictor variable creates an x% increase in response?

I have two different predictors "A" and "B" that can be used (not at the same time) to affect a response variable, "C". Previous data has shown a very strong linear relationship between A and C, ...
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Machine Learning model with aggregated data as training

I would like to predict a LABEL: A,B or C using a classification machine learning model. My data to train the model is like: ...
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How to test for differences between two distributions with percentages?

Imagine there are two distributions: Distribution 1 lists the shares of each ice cream flavor of all favourite flavors in village A: ...
84 views

Black Friday Staffing

Say I am running a store and I have the daily customer count for the last 5 years. I note that the average customer count on Black Fridays is three times higher than the average for the rest of the ...
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Converting standard deviation of percent change to absolute change

I have the following data: However, I wish to know the standard deviation of the absolute change rather than the percentage change. To clarify, for Cloz: absolute change = 0.14*53 = 7.42, and we are ...
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Statistical difference between multiple groups using percentage data

I have 3 groups of data. Group 1 contains 11 values, group 2 contains 7 and group 3 contains 11 values. The values are in the form of 'percentage change over time'. I would like to test to see if the ...
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How to account for missing observations in multivariate regression?

My research concerns the eBay feedback mechanism. users have a "feedback score" (total positive reviews less negative reviews) and a "feedback percentage " $\frac{positives}{positives+negatives}$. ...