postgibbsf90

How does the program work?

This is an interactive program, so just follow the program.

name of parameter file?test.par


POST-GIBBSF90 2.96


Read 1000 samples from round 10 to 10000


Burn-in?
1000
# in the first run, type 0 for burn-in to include all samples

Give n to read every n-th sample? (1 means read all samples)
10 # Type the same number used with a Gibbs sampling program.


# samples after burn-in = 9000

Input files: gibbs_samples, fort.99

output files: postgibbs_samples, postout, postmean, postsd

"postgibbs_samples" is a file contaning all Gibbs samples for additional post analyses.

"postmean" is a file contaning posterior means.

"postsd" is a file contaning posterior standard deviations.

"postout":
******** Monte Carlo Error by Time Series ********
Pos.
eff1
eff2
trt1
trt2
MCE
Mean
HPD
Effective
Median
Mode
Independent
Interval (95%)
sample size
chain size
1 4 4 1 1 1.362E-02 0.9889 0.7788 1.215 70.4 0.9844 0.9861 18
2 4 4 1 2 1.288E-02 1.006 0.777 1.219 84.1 1.006 0.952 18
3 4 4 2 2 1.847E-02 1.66 1.347 1.987 80.3 1.652 1.579 25
4 0 0 1 1 9.530E-03 24.47 24.07 24.84 425.6 24.47 24.53 2
5 0 0 1 2 8.253E-03 11.84 11.54 12.18 395.8 11.83 11.82 2
6 0 0 2 2 1.233E-02 30.1 29.65 30.58 387.8 30.09 29.97 5

 

******** Posterior Standard Deviation ********
Pos.
eff1
eff2
trt1
trt2
PSD
Mean
PSD
Convergence
Autocorrelations
Independent
Interval (95%)
diagnostic
lag: 1
10 50
# batches
1 4 4 1 1 0.1144 0.9889 0.7648 1.213 -0.02 0.853 0.188 0.049 50
2 4 4 1 2 0.1182 1.006 0.7742 1.237 -0.11 0.828 0.111 -0.066 50
3 4 4 2 2 0.1656 1.66 1.335 1.984 0.06 0.828 0.108 -0.021 36
4 0 0 1 1 0.1967 24.47 24.09 24.86 -0.01 0.034 0.029 -0.062 450
5 0 0 1 2 0.1643 11.84 11.51 12.16 0.03 0.032 -0.006 -0.016 450
6 0 0 2 2 0.2429 30.1 29.62 30.57 -0.02 0.07 -0.014 0.037 180

"Pos.": position of each parameter in the parameter file

"eff1" and "eff2": effect number in the parameter file

"trt1" and "trt2": trait number in the parameter file

"MCE": Monte Carlo Error

"Mean": posterior means

"HPD interval (95%)": Highest Probability Density

"Effective sample size": at least > 10 is recommended. > 30 may be better.

"Median":

"Mode": when the distribution of the samples is nor normal, there is a difference between "Mode" and "Mean".

"Independent chain size":

"PSD": Posterior Standard Deviation

"PSD interval (95%)":

"Convergence diagnostic": ratio between first half and second half of the samples should be < 1.0, but it is not useful because it is < 1.0 most of the time.

"Autocorrelations": autocorrelations between two lags. High correlation implies samples are not independent.

"Independent # batches":

Choose a graph for samples (= 1) or histogram (= 2); or exit (= 0)
1

positions

1 2 3 # choose from the position numbers 1 through 6

If the graph is stable (not increasing or decreasing), the convergence is met. All samples before that point shoudl be discarded as burn-in.

print = 1; other graphs = 2; or stop = 0
2

Choose a graph for samples (= 1) or histogram (= 2); or exit (= 0)
2

Type position and # bins
1 20

The distribution should be usually normal.

print = 1; other graphs = 2; or stop = 0
0


*** Log Marginal Density for Bayes Factor ***
after 900 burn-in
log(p) = -179448.742766031

This value could be used when calculating Bayes Factor or DIC.

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