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Questions related from Igor Shuryak
The task involves predicting a binary outcome in a small data set (sample sizes of 20-70) using many (>100) variables as potential predictors. The main problem is that the number of predictors...
11 November 2015 9,241 11 View
For example, cells were exposed to different concentrations of a toxic chemical. Two types of data were measured: (1) the critical concentration above which no cell growth occurred, (2) for lower...
04 April 2015 5,127 24 View
The data provided are percentiles (median, 75th and 90th) from several histograms. The number of observations comprising each histogram is known. The shape of the data distribution in each...
01 January 2015 6,986 5 View
Suppose a mouse study is being designed which aims to address the question of which dose response shape (e.g. linear, quadratic, exponential, etc) best describes the response to a particular...
05 May 2014 3,139 11 View
Some in vitro data using cancer cell lines has been published, which suggests reprogramming of non-tumorigenic cancer cells to cancer stem cells induced by ionizing radiation. Is there some...
04 April 2014 6,403 1 View
Suppose a mathematical model consisting of a system of differential equations is constructed to describe some biological phenomena. Analytic solutions are not available - only numerical ones. Are...
04 April 2014 527 14 View
For example, suppose a certain method was chosen for power/sample size calculation for a future experiment, with the intent to use the same method to analyze the experimental data. But the...
01 January 2014 5,444 20 View
Among the many available methods, which are the most efficient (i.e. require the smallest sample size for defined alpha and beta) and relatively straightforward to implement?
12 December 2013 9,958 10 View
Suppose there are several treatment groups. Within each group there are exponentially distributed data, i.e. the number of counts is proportional to exp[-A*x^B], where A and B are parameters. What...
10 October 2013 452 56 View
Suppose a non-linear smooth function is fitted to some data (e.g. means and standard errors for cell survival after various radiation doses). What are some useful ways to assess goodness of fit...
09 September 2013 8,003 39 View
The issue is how to induce U. maydis cells to attach to the bottom of a culture dish, which is composed of a mylar film. Thanks in advance!
08 August 2013 2,210 0 View
I wonder about this because for such small data sets it is not always clear whether the data are normally distributed, so perhaps results (p values) from both parametric and nonparametric tests...
08 August 2013 7,800 89 View
I used PRCC in one paper (A model of interactions between radiation-induced oxidative stress, protein and DNA damage in Deinococcus radiodurans, available on my page) because reviewers requested...
08 August 2013 6,164 3 View
For example, are metabolically important genes regulated by low concentrations of oxidants (e.g. hydrogen peroxide)?
07 July 2013 8,961 0 View
Suppose nonparametric bootstrapping is used to estimate the sensitivity of the fitted model to parameter values. Does this technique work reasonably well for small data sets (e.g.
07 July 2013 5,889 8 View
There are several commonly used normality tests. I wonder what do you suggest is optimal for small data sets?
07 July 2013 9,103 64 View
For example, suppose a nonlinear model is fitted to a data set. It is possible to map out a region in the parameter space around the best-fit point, within which the residual sum of squares...
07 July 2013 9,053 36 View
I would be grateful for your opinions about the following methodology: Suppose there is a data set consisting of multiple data points with error bars, e.g. in the format X, Y, standard error(Y)....
07 July 2013 3,416 8 View
For example, the same model with 2 parameters is fitted to two data sets. Confidence intervals for each parameter are estimated by nonparametric bootstrapping. The results define two separate (one...
07 July 2013 7,865 14 View
For example, Shewanella oneidnsis was shown to be more sensitive to gamma radiation than most bacteria. Is this a general pattern for metal reducers?
06 June 2013 6,417 2 View
