Instructions Source data xlsx File contains characteristics of

Instructions Source: data. xlsx File contains characteristics of sampling profiles on the rivers. The variables are: • ID profilu – identification number of profile • Region – area where the site is located • Uprava – information if the basin have been somehow influenced by constructions • NV_PROF – altitude of the site • orna_puda – portion of arable land in the profile (in percents) • Saprobita – saprobic index showing the measure of pollution (can be from 0 to infinity) All results copy into the Word. Each Task make to the new list (for orientation in the document)

Tasks Task 1 Check the data – find mistypes and errors. The changes and solution of the problems type into Word document. (e. g. Task 1 – found missing value in row 32 – filled with overall mean of the variable) Task 2 Create in Excel table with descriptive steatistics (N, average, min and max) for parameteres orna_puda and Saprobita. Outcome can be in one table or in two separate tables). The table copy into the Word. Task 3 Create pivot table, which shows: How many of localities have been sampled in each region and how many of them have been influenced by construction. An outcome is one table, which has to be adjusted in format for printing – create fine table nice for printing.

Tasks 2 Task 4 Import the file into Statistica Task 5 Create descriptive statistics for NV_prof, orna_puda and Saprobita in one table. Copy the table into Word. Task 6 Recode the variable NV_PROF into 3 groups: up to 250 m, 250 -300 m and over 300 m. Create boxplot of Saprobita for localities separated into these groups (1 chart). Then test if the saprobity is same for the most diverse groups of NV_PROF (check in the boxplot which two of them have the most diverse median or mean). Interpret the result. Copy boxplot, results of the test into word and add the interpretation.