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1answer
44 views

Calculating a correlation with yes/no answers?

How do you calculate a correlation, that similar to Spearman and Pearson forumlar when you are only comparing one variable (age) to answer given by yes and no. As ages goes up more likely to answer ...
3
votes
2answers
60 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 ...
0
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0answers
13 views

Are correlations transitive between manifested construct variables and other set of variables?

I have seen here that correlation is not transitive, but I wanted to know if such argument applies when we model our assumptions over a construct. More specifically, in my model, I have a construct ...
1
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1answer
106 views

Understanding the p-value in Spearman's rank correlation

I have some pairs of datasets (n=200 or thereabouts), of samples which are non-negative and not normally distributed. I think these pairs of variables are related, ...
-1
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2answers
208 views

Spearman's Correlation using Stata

I am trying to use Stata for the first time to calculate Spearman's Rank Correlation for differences in weight and hemoglobin between annual visits for a small dataset. Do I enter the differences with ...
0
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0answers
43 views

Spearman's Coefficient with excluded ranks

I've got a dataset where I apply one of two transformations to get two scores, Score A and Score B. I then rank Scores A and B and for simplicity's take decide to keep only records where rank(score A) ...
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0answers
83 views

How to rank the elements for use in Spearman rank correlation?

If I have 50 items and I want to compare the top 30. I have several cases to do the ranking , so which one is correct? For simplicity I will replace in the example below 50 items with 5 ( A,B,C,D,E) ...
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0answers
186 views

How to test correlation between an ordinal and a continuous variable?

Which is the best way to test correlation between what I think it is an ordinal variable (the no of weeks worked out of first 8.. which can take values from 0 to 8) and a continuous variable (the ...
1
vote
1answer
60 views

Spearman rank recommended n size

Is there a recommended n to test for Spearman's rank correlation? I have 2 lists of around 10,000 items. I read that Spearman's rank correlation is fine between 10-30 , can I use spearman to compare ...
1
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0answers
76 views

Internal reliability for ordinal scale using Spearman correlation matrix

I have a question about estimating the reliability (coefficient alpha) of a pilot scale by assessing its internal consistency. The pilot questionnaire generates ordinal data, 9 items each with 9 ...
2
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1answer
193 views

Spearman correlation in the presence of many ties - how to spot a problem?

I'm testing the hypothesis that there's a monotonic relationship between two variables. I think I should use a Spearman rank correlation test, since my data don't necessarily meet normality ...
1
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1answer
74 views

How to test for correlation with data that violates assumption of linearity and is not monotonic?

I have sampled 8 individuals (birds) from two regions. For each of these 16 individuals I have sampled 9 feathers that have each grown in sequential order (from 1 to 9). Next I have measure both ...
3
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0answers
59 views

What are the main different/alternative correlation estimators?

I'm looking to learn about the main/popular alternatives when it comes to estimating correlations that I've missed in the following list. The best answer will provide a reference (can be Wikipedia), a ...
3
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1answer
477 views

Reporting coefficient of determination using Spearman's rho

I have two non-normally distributed variables (positively-skewed, exhibiting ceiling effects). I would like to calculate the correlation coefficient between these two variables. Due to the ...
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2answers
280 views

Problem with Spearman correlation in case of many ties

I'm using the Spearman correlation coefficient test for multiple non-parametric ranked categories in excel. I used the built in rank function in excel to calculate the rank of each individuals but i ...
1
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2answers
91 views

How one can improve correlation (higher rho values) on non normal distributions?

No matter what class or book I see, the normal distribution is always advocated. I have been trying to find ways to assess relationship between variables for non normal distributions, most of which ...
0
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0answers
117 views

Scipy Spearman and Pearson [closed]

I had a quick question, I have a table of names with counts, think of it as a frequency distribution. I want to calculate the correlation between two tables, my question is do I need to transform the ...
0
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0answers
142 views

Rank Correlation Statistics Comparison

I am trying to understand the relative behavior of the following rank correlation statistics: Spearman coefficient Kendall Tau / Concordance percentage Normalized Gini coefficient (area under curve ...
2
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0answers
320 views

Cor.test and statistical test values for spearman correlation, how to make sense of them?

I am trying to make sense of the spearman test I am getting as a result of using cor.test on R package. This page seemed to me to inform that I should care not only for p-values and rho values from ...
0
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1answer
182 views

Can't get observation-wise factor scores from psych package

After R reads the data, say- ...
1
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1answer
129 views

Effect of treatment on correlation between two sets of variables

Imagine I wish to see the effect of some treatment on the correlation between two groups of variables, which I measure with Spearman's rank correlation coefficient. Treatment A gives a Spearman's ...
1
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2answers
1k views

Whether to use Spearman's rho or multiple regression to examine relationship between two Likert scales?

I am doing my thesis and have absolutely no previous experience in statistics. I have constructed several Likert scales by forming composites scores each based on 4-6 items which tests the level of ...
4
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2answers
543 views

What does it indicate when the Spearman correlation is a definite amount less than Pearson?

I have a bunch of related datasets. The pearson correlations between pairs of them are typically definitely larger than the spearman correlations. That suggests any correlation is linear, but one ...
1
vote
1answer
115 views

I have a statistic, how do I calculate its distribution?

I am comparing images for correlation. The images are all correlated, but I would like to determine when one pair is much more highly correlated, relative to another pair. I am using as a statistic ...
3
votes
1answer
978 views

Spearman's rank correlation for a beginner: Sample size and Interpretation

I am a computer scientist performing research, which includes calculating the Spearman rank correlation of two lists, one ranked by a human, another by a computer program. I have the following ...
0
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1answer
147 views

Ranked/Ordinal data - 3 variables

I have the following hypothesis: Novice drivers perceive road environments as more difficult when there are more pedestrians. I have the following data: The category each driver falls in to (1. ...
2
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1answer
140 views

Rank correlation and demonstrating reasonable proficiency in rank ordering

Background I'm working on a new effort estimation model (dissertation work) which involves software engineers organizing tasks (rank ordering) in order of increasing effort based solely on their ...
1
vote
1answer
2k views

Calculating P-value for Spearman's rank correlation coefficient example on Wikipedia

The Wikipedia article Spearman's rank correlation coefficient contains an example for calculating ρ. At the end of the sections is the statement "...with a P-value = 0.6864058 (using the t ...
2
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1answer
534 views

Spearman or Kendall correlation?

I would like to assess the correlation between a 7-category ordinal variable (X) and a number of other variables some of which are ordinal with 3-6 categories, others are continuous and a couple are ...
3
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1answer
2k views

How to calculate a confidence interval for Spearman's rank correlation?

Wikipedia has a Fisher transform of the Spearman rank correlation to an approximate z-score. Perhaps that z-score is the difference from null hypothesis (rank correlation 0)? This page has the ...
5
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1answer
1k views

How does the Goodman-Kruskal gamma test and the Kendall tau or Spearman rho test compare?

In my work, we are comparing predicted rankings versus true rankings for some sets of data. Up until recently, we've been using Kendall-Tau alone. A group working on a similar project suggested we try ...
3
votes
1answer
143 views

What are other good ways of finding out the degree of similarity between lists?

I have a ground truth list, call it A, and I have different methods for generating lists that should be somewhat similar.. I want to decide which method of these generates a list that is most similar ...
6
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2answers
2k views

Significance test on the difference of Spearman's correlation coefficient

(Thanks a lot for the quick responses! I did a poor job of asking the question, so let me retry.) I do not know how to find out whether or not the difference between two Spearman's correlations is ...
4
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0answers
103 views

How to average Spearman correlations? [duplicate]

Possible Duplicate: Averaging correlation values I have a number of users, and for each user I have 2 ordered lists of items (one is from observation, one is generated by an algorithm). ...
1
vote
2answers
163 views

Why are all the spearman's rho correlations with one variable low when the other variables all have moderate correlations?

I was wondering what could be the reasons for a very low Spearman correlation, as low as 0.01-0.06. Basically no correlation even exists! All my other variables have moderate correlations except any ...
4
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2answers
737 views

Pearson and Spearman correlations - how to determine if they are “similar”?

I would like to know if there are any rules to determine if Pearson's r correlation values are similar to Spearman's rho? For example, if r = -.207 and rho = -.282, are these similar enough to just ...
2
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2answers
557 views

Can Spearman's correlation be run on z scores?

I understand the logic of standardising raw data that is based on different scales into z scores so that they can compared, for example comparing a score of 75 out of 100 in one test versus 65 out of ...
12
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1answer
2k views

What could cause big differences in correlation coefficient between Pearson's and Spearman's correlation for a given dataset?

The Pearson's coefficient between two variables is quite high (r=.65). But when I rank the variable values and run a Spearman's correlation, the cofficient value is much lower (r=.30). What is the ...
2
votes
1answer
206 views

How to analyse a study looking at relationship between one set of five items (predictors) and a second set of five items (outcomes)

My study is about customers’ perception of the effectiveness for a Malaysia corporate Weblog. In my study, customers’ perception of the effectiveness defined as perceived ease of use, perceived ...
4
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0answers
239 views

Adjust a large set of Spearman correlation analyses for multiple testing [duplicate]

Possible Duplicate: Threshold for correlation coefficient to indicate statistical significance of a correlation in a correlation matrix Context I am doing an exploratory study to ...
1
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0answers
161 views

Spearman correlation of two Weibull distributions

Is there a way to find the Spearman correlation between two Weibull distributions? I need it as a parameter in a copula function for the joint Weibull distribution. I learned that using the Pearson ...
14
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5answers
68k views

How to choose between Pearson and Spearman correlation?

How do I know when to choose between Spearman's $\rho$ and Pearson's $r$? My variable includes satisfaction and the scores were interpreted using the sum of the scores. However, these scores could ...
3
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2answers
1k views

What correlation coefficient and graph is appropriate with this data?

I'm not in Statistics field. I conducted the case study and collected the data as shown below I have data as shown in the table below: I would like to find correlation coefficient from this two ...
8
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1answer
308 views

Measuring correlation of trained neural networks

I am training an artificial neural network (backpropagation, feed-forward) with non-normal distributed data. Beside the root mean squared error, literature does often suggest the Pearson correlation ...
5
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2answers
2k views

How to estimate a critical value of Spearman's correlation for n=100?

I have searched a lot, and I can only find tables that show critical values up to n=30. Can someone provide, or point me to, a simple method of estimating this value for different $\alpha$?
7
votes
1answer
271 views

Are there bounds on the Spearman correlation of a sum of two variables?

Given $n$-vectors $x, y_1, y_2$ such that the Spearman correlation coefficient of $x$ and $y_i$ is $\rho_i = \rho(x,y_i)$, are there known bounds on the Spearman coefficient of $x$ with $y_1 + y_2$, ...
3
votes
3answers
901 views

Is Spearman's correlation coefficient usable to compare distributions?

I have distributions from two different data sets and I would like to measure how similar their distributions (in terms of their bin frequencies) are. In other words, I am not interested in the ...