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Start Over Rights http://creativecommons.org/licenses/by-nc-sa/4.0/ Subject statistika

3. Statistical characteristics and trends of mean annual and monthly discharges of Czech rivers in the period 1961-2005

Creator:
Fiala, Theodor
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
M-day discharge, reference period, statistics, trends, M-denní průtok, statistika, referenční období, and trendy
Language:
Slovak
Description:
The Surface Water Department of the Czech Hydrometeorological Institute in 2006 selected a new period for the evaluation of hydrological characteristics of mean daily discharge series. Initially, two fortyyear long periods were considered: 1961-2000 and 1966-2005 and the period of 1961-2005 was finally accepted. Comparison of the still used 1931-1980 period with the new one was carried out using the data from 50 Czech gauging stations that had continuous data time series. The mean long-term runoff of Czech rivers changed very little from 1931-1980 to 1961-2005. Comparison of the variation coefficients brought similar results. However, among specific M-day discharges the low flow values (e.g. Q355d) showed a significant increase. This might reflect not only natural causes but could suggest anthropogenic factors as well. Trend analyses started with testing mean annual runoff at 65 Czech gauging stations that were not influenced by human activity. 34 stations showed an increasing trend and 31 a decreasing trend. However, the trend was statistically significant only at one station. Trends of individual months dramatically differentiate. In January through March the increasing trends prevail. March trends show the highest number of stations with a significant increase. The three following months are complete opposites in which decreasing trends dominate. In May and June, not a single increase was recorded and many decreases were statistically significant. Almost no significant trends were examined in the months of the second half of the year. and V posledních měsících se oddělení povrchových vod ČHMÚ zabývalo výběrem období pro výpočet nových hydrologických charakteristik M-denních průtoků na českých tocích. Uvažována byla čtyřicetiletí 1961-2000 a 1966-2005, nakonec však bylo přijato období 1961-2005. Na datech z 50 vodoměrných stanic, které měly nepřerušené řady pozorování, bylo uskutečněno první srovnání statistických charakteristik období 1931-1980 (doposud používané) a 1961-2005. U nového období byly u neovlivněných stanic vyhodnoceny trendy průměrných ročních průtoků a průtoků jednotlivých měsíců.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Statistics in three biomedical journals

Creator:
Tomáš Pilčík
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, statistika, odborné časopisy, biomedicína, statistics, professional journals, biomedicine, usage, biomedical journals, assessment, 14, and 612
Language:
English
Description:
In this paper we analyze the use of statistics and associated problems, in three Czech biological journals in the year 2000. We investigated 23 articles Folia Biologica, 60 articles in Folia Microbiologica, and 88 articles in Physiological Research. The highest frequency of publications with statistical content have used descriptive statistics and t-test. The most usual mistake concerns the absence of reference about the used statistical software and insufficient description of the data. We have compared our results with the results of similar studies in some other medical journals. The use of important statistical methods is comparable with those used in most medical journals, the proportion of articles, in which the applied method is described insufficiently is moderately low., T. Pilčík., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Trend analysis of rainfall-runoff regimes in selected headwater areas of the Czech Republic

Creator:
Kliment, Zdeněk, Matoušková, Milada, Ledvinka, Ondřej, and Královec, Václav
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
statistics, trends, rainfall-runoff regime, air temperature, snow parameters, headwaters areas, Czech Republic, statistika, trendy, srážko-odtokový režim, teplota vzduchu, sněhové charakteristiky, pramenné oblasti, and Česká republika
Language:
Slovak
Description:
The main aim of this work is to evaluate the development of rainfall-runoff regime in selected river basins of the Šumava Mountains (Bohemian Forest), the Jeseníky Mountains and the Krušné Mountains (Ore Mountains) in the last 50 years. Besides the identification of inhomogeneity in time series of mean discharges, rainfall amounts, temperature and snow cover data, the work deals with an analysis of trends using annual and monthly data. Different methodological tools for identification of changes and trends in hydro-climatic time series have been introduced in this study, especially different methods of statistic testing and an application of Mann-Kendall seasonal test. The results have been compared not only from the point of view of the methods applied here, but as well from the viewpoint of geographical difference of the mentioned areas. and Hlavním cílem předložené studie je zhodnotit vývoj srážko-odtokového režimu ve vybraných povodích v oblasti Šumavy, Jeseníků a Krušných hor za posledních 50 let. Vedle zjišťování nehomogenit v časových řadách průměrných průtokových, srážkových, ale i teplotních a sněhových dat se práce zabývá analýzou trendů na úrovni ročních hodnot a jednotlivých měsíců. V práci jsou představeny různé metodické nástroje ke sledování změn a trendů v hydroklimatologických řadách, zejména různé metody statistického testování a aplikace Mann-Kendallova sezónního testu. Výsledky jsou porovnány nejen z hlediska použitých metod, ale i geografické rozdílnosti sledovaných území.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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