









Quantitative
Parasitology 3.0



This parasitology software provides statistically correct ways to
analyse the highly aggregated (rightskewed) frequency distributions
exhibited by parasites. QP3.0 is recommended to describe parasitic
infections within a sample of hosts and to compare parasitic infections
across different samples of hosts. 
Download
and isntall QP3.0

or
go to our new
QP on the Web


QP3.0 is free for distribution and use in education and science.
When using it for academic purposes please cite:
Reiczigel J, Rózsa L 2005. Quantitative Parasitology 3.0.
Budapest. Distributed by the authors.
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Alternatively, you can consult and cite the paper that introduced this
software:



Rózsa L, Reiczigel J, Majoros G 2000.
Quantifying parasites in samples of hosts. Journal of Parasitology,
86, 228232. 


Note that a some of the methods incorporated in QP3.0 were either newly
introduced or reconsidered in more recent articles listed below.
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How to run
Runs under Windows. After download, unzip the file and
find a folder named 'QP30'.
Do not remove the files from the folder. Within this folder, you just
•
right click (i.e. use the right mouse button to click) the file
named '_qp30.exe'
•
then select 'run as administrator'.
In Windows versions earlier than Vista (<2003) no need for right click;
you just click and run '_qp30.exe'.
No
Mac version is available.
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Statistical tools available in QP3.0
1. To describe parasitic infection of a single sample of hosts:
Descriptive statistics (N hosts,
prevalence, mean & median intensity, variance/mean),
Two alternatives to calculate an exact
confidence interval for the prevalence
Clopper  Pearson method (this is more traditional),
Sterne or Wald method (this is more advanced, see Reiczigel 2003),
Bootstrap (BCa) confidence interval for
the mean intensity,
Exact confidence interval for the median
intensity,
Bootstrap (BCa) confidence interval for
the mean abundance,
Bootstrap (BCa) confidence interval for
the mean crowding (see Reiczigel et al. 2005a),
Aggregation indices (variance/mean,
index of discrepancy, and k of the negative binomial),
2. To compare parasitic infections between two samples of hosts:
Descriptive statistics (N hosts,
prevalence, mean & median intensity, variance/mean),
Two alternatives to compare prevalences:
Chisquare Test (this is a more traditional way),
Fisher's Exact Test (this is a better alternative),
Unconditional Test (most advanced, see
Reiczigel et al. 2008.) NEW (02. 01. 2010.)
Bootstrap tTest to compare Mean
Intensities,
Mood’s Median Test to compare Median
Intensities,
Stochastic equality of intensity
distributions (see Reiczigel et al. 2005b),
Bootstrap tTest to compare Mean
Abundances,
Comparison of Mean Crowding (see
Reiczigel et al. 2005a),
3. To compare parasitic infections among samples of hosts:
Descriptive statistics (N hosts,
prevalence, mean & median intensity, variance/mean),
Two alternatives to compare prevalences:
Chisquare Test to compare Prevalences (this is a more traditional way),
Fisher's Exact Test to compare Prevalences (this is a better
alternative),
Mood’s Median Test to compare Median
Intensities.
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Why do we apply several statistical tests in parallel with each other?
How to choose the approprite statistical procedures for a particular
study?
Find a brief technical guide here.
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Further readings
Some of the methods listed above have been described or discussed in
these articles. 


Reiczigel J 2003. Confidence intervals for the binomial parameter: some
new considerations. Statistics in Medicine, 22, 611621. 


Reiczigel J, Lang Z, Rózsa L, Tóthmérész B 2005. Properties of crowding
indices and statistical tools to analyze crowding data. Journal of
Parasitology, 91, 245252. 


Reiczigel J, Zakariás I, Rózsa L 2005. A bootstrap test of stochastic
equality of two populations. The American Statistician, 59,
156161. 


Reiczigel J, AbonyiTóth Z, Singer J 2008. An exact confidence set for
two binomial proportions and exact unconditional confidence intervals
for the difference and ratio of proportions. Computational Statistics
and Data Analysis, 52, 504653.
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Bug fixed
There was a mistake slightly affecting the confidence intervals for mean
intensity and mean abundance in a former version of Quantitative
Parasitology. QP2.0 downloaded after 02. 04. 2003. and all copies of QP
3.0 are free of this error.
Contacts
Mail to reiczigel.jeno (at) gmail.com regarding biostatistics and
computation; or mail to lajos.rozsa (at) gmail.com regarding
epidemiology or biology.
Supported by
Hungarian Academy of Sciences, Hungarian National Scientific Research
Found (OTKA T 049157), Szent István University (NKB 2001KUT5018)
Copyright Notice
The papers listed above has been published at different peerreviewed
journals. Copyright and all rights therein are retained by the
respective publishers. This material may not be copied or reposted
without explicit permission. Use for scholarly and educational purposes
only.



This
page is online since 27^{th} of Nov, 2001.
Last
updated on the 1^{st} of June, 2011.
Maintained
by Lajos Rózsa. 
Visits
since the 9^{th} of Jan, 2010.



