# Tagged Questions

A population is the entire set of units from which a sample may be drawn.

21answers
4k views

### Locating freely available data samples

I've been working on a new method for analyzing and parsing datasets to identify and isolate subgroups of a population without foreknowledge of any subgroup's characteristics. While the method works ...
4answers
3k views

### Statistical inference when the sample “is” the population

Imagine you have to do reporting on the numbers of candidates who yearly take a given test. It seems rather difficult to infer the observed % of success, for instance, on a wider population due to the ...
2answers
310 views

### Population model to model year to year dynamics

My task is to assess how various environmental variables affect annual population fluctuations. For this, I would use a model like:  \mbox{log} ( \mu_{i,j+1} ) = \mbox{log} ( \mu_{i,j} ) + R_{j} + ...
5answers
11k views

### What is the difference between N and N-1 in calculating population variance?

I did not get the why there are N and N-1 while calculating population variance. When we use ...
3answers
34k views

### What is the difference between a population and a sample?

What is the difference between a population and a sample? What common variables and statistics are used for each one, and how do those relate to each other?
2answers
203 views

### Combining the results of two surveys

Someone has surveyed a number of people and put the results in a database (Survey 1). Each observation has additional information that, for any subpopulation (men only, young only, etc.), gives a ...
3answers
849 views

### Identifying the population and samples in a study

I apologise for the silliness of this question. I ran an e-learning experiment using a class of undergrads. Participation was voluntary, so only half of the class participated. I know that my sample ...
2answers
173 views

### Population Variance and Sample Variance

How is it that lowering the number of frequence,$n$ by $1$ in the for formula for Population and Sample Variance account for the discrepency of using sample rather than population. I mean how is ...
4answers
201 views

### Is any quantitative property of the population a “parameter”?

I'm relatively familiar with the distinction between the terms statistic and parameter. I see a statistic as the value obtained from applying a function to the sample data. However, most examples of ...
3answers
531 views

### Estimating population size from the frequency of sampled duplicates and uniques

There is a web service where I can request information about a random item. For every request each item has an equal chance of being returned. I can keep requesting items and record the number of ...
1answer
1k views

### Does transformation of r into Fisher z benefit a meta-analysis?

Usually $r$ is transformed into Fisher $z$ to test difference between two $r$ values. But, when a meta-analysis is to be performed, why we should take such a step? Does it correct for measurement ...
3answers
956 views

### Significance test for non-normal population?

I'm a journalist, and I am trying to work out whether hospitals that are in political districts with low majorities (i.e. where the political representative is fighting hard for his or her seat) are ...
1answer
91 views

### Sampling distribution of means

Im working through a textbook atm and Ive read that the mean of "the sampling distribution of means" is the same as the "populations" mean. To construct the sampling distribution of means, i need to ...
2answers
68 views

### Inferring a likely full population from multinomial measurement or survey data

Assume that we have one or several multinomial samples (e.g., surveys) taken from our population. While inferring characteristics (such as mean values, correlation, ...) from a multinomial sample is a ...