Hey peeps any mathematical genius in my list? Pls ping, I need a solution to a statistics questions.

UNIT: Research Methods for Postgraduates
(ENVI 1096) Statistics Assessment

SET: Wednesday, 4th March 2015

DEADLINE: Sunday 29th March 2015

SUBMISSION Electronic via Moodle
__________________________________________________________________________________________

Data for all exercises is contained in the Excel spreadsheet MSc StatsAss 2014-15 Data.xls.

EXERCISE 1

The data in this exercise are average heavy metal concentrations in freshwater fish from a survey of agricultural and urban catchments in the UK.

Catchments were randomly chosen, fish were collected from each catchment, and the average heavy metal concentration in the fish was measured (in µg/g).

There is one value for each catchment, with a total of 42 agricultural catchments and 30 urban catchments in the study.

The investigators want to know:

Is there a higher heavy metal concentration in fish from the urban catchments, compared to those from the agricultural catchments?

EXERCISE 2

From 1975 to 2008 investigators collected peak discharge data for 352 storm events from two catchments in the same relative location (one forested, one comprising mainly grassland).

Both catchments have similar elevation and lie on western facing slopes.

Discharge (sometimes called flow) is measured in units of volume per time: in this data set, discharge is recorded in "cubic metres per second", or m3/s.

The forested catchment in this study has an area of about 45 square kilometres (km2) while the grassland catchment has an area of 21 km2.

To eliminate the effects of area on discharge, the data has been adjusted or "normalized" to give what is referred to as "Unit Discharge", with measurement units in "cubic metres per second per square kilometre" (m3/s/km2).

Unit discharge tells us how much flow comes off a standard sized piece of land in the catchment, on average.

The investigators want to know:

(a) Is there a difference in the average peak discharge between the two different catchment types?

(b) Is there any evidence of a correlation between the discharges from the two catchments, and if so, is it significant and what is its magnitude?

(c) Is there any evidence that there has been a change in average peak discharges pre- and post-2000 in forested and/or grassland catchments?


Produce a report which provides the following:

Your answer for each question should be a short paragraph containing the following:

The Null and Alternative Hypotheses you are using;
What method/test do you believe is the most appropriate to analyze these data? Explain your choice and provide any evidence to back-up your explanation (for example if you stipulate a parametric test of any sort, then you must provide evidence that the data you are testing are normally distributed);
An appropriate concluding answer to the questions set.

The key thing to think about is the use of the most APPROPRIATE test for each exercise. Often this will be based on your interpretation of the nature of the data, and hence, there may be more than one way to answer the questions. BUT you must justify what you do. In addition, you are allowed to present results from only one test:

FOR EXAMPLE – DO NOT CARRY OUT BOTH A T-TEST AND A MANN-WHITNEY TEST FOR DIFFERENCES; CHOOSE ONE OR THE OTHER;

DO NOT CARRY OUT BOTH A 1-TAILED AND A 2-TAILED TEST – CHOOSE WHICHEVER IS APPROPRIATE.

Your mark for this assignment will be based on your explanation of the choice of analysis and whether you provide appropriate answers to the investigator's questions. Marks will be deducted if you fail to fully justify what you do, and present results from multiple tests.


Submit your work electronically by the deadline of Friday 4th April 2014 (11.59pm).

You will NOT be allowed to submit electronically after this deadline, and this WILL RESULT IN NO MARKS BEING AWARDED UNLESS YOU HAVE EXTENUATING CIRCUMSTANCES.

______________________________________________________________________________________

DO NOT SIMPLY SUBMIT AN SPSS OUTPUT FILE.

YOU MUST PRODUCE A WORD DOCUMENT.

NOTE: YOU CAN COPY AND PASTE APPROPRIATE DIAGRAMS AND TABLES FROM SPSS OUTPUTS INTO YOUR DOCUMENT.

E be Like say this One too Strong for me oh!!