Tagged Questions
3
votes
2answers
152 views
Cluster Big Data in R and Is Sampling Relevant?
I'm new to data science and have a problem finding clusters in a data set with 200,000 rows and 50 columns in R.
Since the data have both numeric and nominal variables, methods like K-means which ...
2
votes
0answers
28 views
seeking statistical measures to use when evaluating a facial photo's “quality”
I have a large set of facial photos and a facial feature finder which helps me locate faces with a general idea of the location of the eyes, nose, mouth, and a curve outlining the face. These facial ...
1
vote
1answer
82 views
What should I do while designing stratified cluster randomized sampling survey if cluster size is large/smaller than I expect?
I am design a sampling strategy for a health survey in long-term care facilities (LTCFs). I refer to the article here
and want to ask question about the cluster size.
I am thinking of doing a ...
4
votes
3answers
208 views
How to sample natural numbers, such that the sum is equal to a constant?
Say I have $N$ items that are partitioned / clustered and I want to randomly repartition these items, such that the distribution of sizes of the clusters is 'similar' to those that I already have. I'm ...
3
votes
0answers
153 views
How do I adjust standard errors in a research study in which the control group is constructed via matching with replacement?
I have a treatment sample of 200 firms. I'm using propensity score matching to pair each treatment observation with one control (sampling with replacement, in order to minimize bias associated with ...
1
vote
2answers
208 views
How to sample clustering to estimate precision and recall?
There is a system containing $N$ clusters and in each cluster there are some elements. The clusters' sizes varies dramatically and most of the clusters are singletons.
I need to know the precision ...
1
vote
1answer
84 views
Finding k-representatives from a 2 dimensional data set
I have a data set for second hand vehicle sales with 2 variables price and kms covered. If we plot these data in a 2-dimensional plane, the points will form scattered chart. I would like to select k ...
