A brief numerical description of a set of data.

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3
votes
3answers
61 views

glm in R - which pvalue represents the goodness of fit of entire model?

I am running glms in R (generalised linear models). I thought I knew pvalues - until I saw that calling up a summary for a glm does not give you an overriding pvalue representative of the model as a ...
0
votes
0answers
16 views

How to implement Exponential Histograms

I am having trouble in understanding the concept of exponential histograms. They are known to be much efficient for maintaining statistics. I have read it in this article but cant understand how they ...
2
votes
0answers
12 views

Quantitative tail sizing

What is the most generic way of deciding whether the tail of a dataset is long or short? In other words, what would be the unit-free summary metric m that could be ...
2
votes
0answers
10 views

How to prove that the permutation of the points are the minimal sufficient statistics for Cauchy distribution?

I see this everywhere that the permutation of the samples $X_{(1)}, ..., X_{(n)}$ is the minimal sufficient statistic for the Cauchy distribution [1]. It is clear that it is a sufficient statistic,but ...
-1
votes
1answer
41 views

Appropriate statistical analysis to use

I have built and tested a computer application, which involved two participant groups (Group-A with existing knowledge of databases and Group-B without knowledge of databases). I was required to apply ...
3
votes
1answer
33 views

Is there a way to characterize the position of a point in a distribution that takes higher moments into account?

When summarizing a location in a distribution, we can take the mean into account by simply calculating $x-\mu$. We can take the standard deviation into account by calculating a Z score ...
2
votes
1answer
45 views

Mann-Whitney U test when only summary data (mean, sd, sample size) are available

When raw data is not available, which normally occurs when we obtain our data from different scientific papers, how is it possible to perform a Mann-Whitney analysis to test whether two samples are ...
1
vote
1answer
20 views

What's the meaning of 'statistical break'? And how to calculate it?

I am reading a paper named "EPRI-GTC Overhead Electric Transmission Line Siting Methodology", and in this paper the author uses "the first statistical break in its histogram" to determine the corridor ...
1
vote
0answers
26 views

A walk through my datas

I wish to study the effect of a categorical factor on the rate of increase of some parameter Y along a given X explanatory variable. My datas looks like: ...
1
vote
0answers
25 views

Interpreting summary output in R [duplicate]

I'm fitting a linear model to a dataset. I've reduced the model from 7 variables to 3 and as part of that I've transformed one of my variables (wt) in order to get a better fit. For my final model, ...
1
vote
1answer
37 views

measure for jobs/complaints ratio

I have a number of jobs in a database which can receive complaints. A job can receive several complaints and a job has an associated supplier. I would like to identify the worst performing suppliers. ...
0
votes
0answers
8 views

how to take the sum in using 3 point scale

I have conducted a survey through a questionnaire which consists of 45 questions grouped under 6 independent variables and apart from this i have taken 3 dependent variables which i want to regress ...
1
vote
1answer
45 views

What statistical analysis should I use for my study?

In my psych class we were testing to see if groups of men or groups of women would be more helpful in an emergency situation (we are testing for the bystander effect), and we are testing to see if ...
0
votes
1answer
39 views

regarding the explanation of interaction plot

I was trying to draw an interaction plot for two predictor variables as follows: interaction.plot(xtest[,2],xtest[,8],y) I got the following plot. I do not know ...
0
votes
1answer
28 views

Average time series data (summarize) increasing slope of line

We are working on time series data forecasting. Our input data set is large, so thought to average two consecutive data points and reduce it to half the size. But we have observed that average values ...
0
votes
0answers
35 views

difference between machine learning and stastitical technique [duplicate]

Is there any difference between machine learning and stastitical techniques. I have searched a lot some researchers say that there are some overlap some are saying there is no difference.Can you give ...
1
vote
0answers
36 views

Should descriptive statistics on percentages data be weighted?

I'm trying to put together descriptive statistics for a set of differently sized groups of students. For each group of students, let's say I know the # of students who are left handed. I'd like to ...
1
vote
1answer
19 views

Best statistical method to show different performance week over week

I am trying to get best statical method to show performance of accumulative revenue by customer compare week over week. Currently I have about over 100 customer charts compare by hour from same day ...
0
votes
0answers
16 views

Getting estimates of hospital specific stroke admissions data

I am analysing a small data set on stroke process of care gathered from public sources but don't have access to hospital specific emergency stroke admissions over a period of time data except for ...
0
votes
0answers
7 views

What are the Outputs of analytic process

I am trying to understand the different types of output generated as a result of the analytic process. If my customer does not understand Linear regression, Random Forest, then what is the best way of ...
0
votes
0answers
22 views

regarding the statistics to test the impact of some subset values on a given variable

For a given variable, there is a set of values. We know that these values can belong to different clusters. For instance, a lot of values center around a small value while other values center around a ...
0
votes
0answers
51 views

How to measure defense and attack of a soccer team using goals

i've been trying to come up with a way to measure attack and defense of a team in terms of goals scored and received. The only thing that has crossed my mind is to divide the number of goals ...
1
vote
1answer
41 views

How to quantify the importance of a win in soccer?

I've been thinking lately that the "importance" of a win in a soccer match depends on how good the opponent is. Let's take the spanish league for example. You have some elite teams like Barcelona FC, ...
1
vote
0answers
35 views

questions on characterizing a variable into ordered, categorical or continuous

When building the regression models, some independent variables are of the following type x={1, 2, -100.1, 200.1, 300, 0, 0, 0, 0, 4000} If there exists an ...
0
votes
0answers
17 views

Summary of Probabilities

I am trying to summarize the ages of a population of five people. I have the following observations with an "Average" calculated at the end: ...
0
votes
0answers
30 views

Drop1() and Summary() on lm object

I need to analyse unbalanced data through linear regression: modJuin=lm(TleafMax~TairMax*orientation, na.action="na.exclude", data=aJuin) "TairMax" is a ...
0
votes
0answers
9 views

stat about variance of error

I have 2 population A and B: A contains the data with errors, while B contains the correct data. I want to find out a way to statistically correct the error of A. I compute the error from every row ...
1
vote
0answers
40 views

ranking based on lower confidence interval

I have a database of bridge scores from a local bridge club that effectively contains for this question, three fields: name, ...
1
vote
2answers
42 views

Presenting summary statistics

For a section reporting descriptive statistics should I use the non-transformed variables $x$ or the transformed variables used in the regression analysis (e.g. differenced logs of a variable, $\Delta ...
0
votes
2answers
75 views

Stratified or multi-stage sampling?

I just started volunteering with a small organization that wants to estimate the average and total number environmental trouble spots in a large US city. They have a clear definition of an ...
1
vote
0answers
18 views

How to project video viewcount based on historicals?

My goal is to create a formula that can give an indication of how a YouTube channel's video will perform in the first 30 days of its lifespan and eliminate viral video / "lightening in a bottle" ...
0
votes
0answers
25 views

UnReSolved Mean Adjust DataSet to achieve .5 Mean [duplicate]

Update So I've done some of my own work on transformational methods, and the best I can get is what I call an s transform as detailed in this workbook; however, various attempts at trying to mean ...
1
vote
0answers
30 views

Is it random and representative of all Australians if 200 people are interviewed from the the Sydney area Phone book?

1000 people selected, 200 replies those were taken in as data. Is this representative of Australian even though it's just in the sydney area. Is it random?
0
votes
1answer
110 views

Summarizing a lognormal distribution with geometric mean and standard deviation

I have some data that I strongly suspect are lognormally distributed, and I'd like to summarize the distribution using the mean and standard deviation. I've read that with lognormal distributions the ...
7
votes
2answers
82 views

Visually summarising a mess of directed line segments

I have a data set of millions of directed line segments. The line segments are sequential - it's a climatic variable (sensible heat), with observed and simulated values at half-hourly intervals. I'm ...
0
votes
1answer
97 views

Calculate odds ratio and confidence interval from p-value

I am working with summary statistics from a genome-wide association study (p-values, odds ratio, standard error). The test statistic in the dataset was inflated, so I have had to correct for this ...
2
votes
1answer
52 views

how to calculate a summary value and statistical error in time series

I have a set of data that comes for empirical measurements over a number of days. From the beginning of the experiment to the end of it, every five minutes temperature was measured inside (Ti) and ...
0
votes
0answers
17 views

How do I perform a statistical analysis on an intervention based study?

I am trying to get my head around the best way to analyse a study. The study comprises of persons that get given a number of up to 10 different interventions, whereby hospital admission frequency is ...
0
votes
0answers
56 views

Sum of Variance or Standard Error?

My end goal is to present the average travel time for a corridor and the standard deviation (or standard error) of that travel time. I'm not sure what to present to be statistically correct, here is ...
0
votes
0answers
25 views

Hierarchical clustering of repeated measures in a few locations

I have a water quality data (value) measured 10 times (every month - data) on three depths (shallow, medium, deep) in five location (A, B, C, D, E): I want to find in which location values are ...
0
votes
0answers
17 views

What advantages should a weekly latency report give me over a daily report

We have a daily report that takes the days p90 website latency data and compares it with the same day over the past four weeks and tells whether the p90 latency has gone up or down for a particular ...
1
vote
1answer
111 views

$t$ test vs $\chi^{2}$ once sample is split into two groups?

I would appreciate some guidance regarding the use of a t test vs $\chi^{2}$. I am looking at some small set of demographic data (n only 13). I have divided up the sample into two sets, those with ...
2
votes
1answer
87 views

Is it Poisson distributed, and if so, what's its meaning?

I've collected data from my website. The website is about cars. The data are about user reviews and the cars. what we see in the graphs is the probability of some car type (Ford Focus 2008) to have X ...
5
votes
0answers
60 views

Weighting on tables

I have a question about terminology. Suppose I have data categorized by three factors A, B, and C, with cell means $\bar{y}_{ijk}$ and cell frequencies $n_{ijk}$, where $i$, $j$, and $k$ index A, B, ...
3
votes
0answers
120 views

Better estimator of expected sum than mean

I am trying to find the optimal estimator for the maximal expected $\Sigma X_i$ where $X_i$ is sampled from an unknown distribution which is chosen to be maximal. To clarify and simplify, there are ...
0
votes
1answer
92 views

What is the z-value of glm model parameters?

I know what the z-value of a single observation is, that is explained in Wikipedia. But what is the z-value of a parameter in a glm model?
0
votes
1answer
43 views

Comparing salaries in different countries

I have a number of salary figures for roles that I want to compare across various countries. Obviously each country has their own currency and living costs. A simple way of comparing would be to use ...
0
votes
0answers
31 views

Variation within and between groups

So in my data, I have parameters(~800) and each parameter has 14 different groups. I individually know the mean and standard deviation within each group for each parameter. The data within each group ...
1
vote
0answers
137 views

Variance of sample mean in a binomial distribution

I'm trying to derive that the variance of phat = pq/n. I'm unfortunately not getting that. Please tell me where I'm going wrong... ...
1
vote
0answers
68 views

Computation of parameters of truncated normal distribution

I have a numeric data sample with mean $\mu$ and standard deviation $\sigma$. I believe that this data has a normal distribution truncated to $[0,1]$. Is there a reasonably simple formula for ...