### Water analysis report | Statistics homework help

__Please read the following very carefully__:

· This is your first summative assessment on this course. It is worth 50% of your total marks.

· You have 3 weeks to work on your report which must be submitted no later than 11:59 pm on Sunday 21st February.

· Your report must be Your Work Only. It has been designed such that each student chooses their own strategy. If the strategy you choose is similar to any other students’ strategy, then you will be asked to attend an interview and explain why. If you cannot explain why, you will be penalized. It must be your work only.

· You may discuss the report with your tutor over the three weeks before submission. Your tutor will help you with the interpretation and quality of your Report statistics, but *they will not help you with your strategy*. You must decide on the best strategy and *there is no preferred strategy.*

· It is a short report. Only 600 words. So, you will need to** focus** on what is **most important**. There is no room for repetition or redundant material.

· You should put all your Excel calculations and diagrams in an appendix. Your appendix must be no more than 4 pages – all with a font size of *no less than 11pt.*

· Please read the Report assessment scenario very carefully and make sure you understand the primary task. Do this *before* starting to analyse the data provided.

· Lastly, your Report must be tidy and well presented with clearly labelled tables and charts. This is a formal report, and it should be designed to impress.

**Assessment Scenario:**

There has been a pilot study of the water quality in the water reservoirs supplying the local area. In total, **89** reservoirs supply the area with fresh drinking water. In recent times, the area’s needs have changed significantly in terms of water volumes and quality.

The pilot study aims to understand the key factors affecting water cost and quality. One possible outcome of the study is a programme of re-building the reservoirs to aid water quality. However, this outcome is only likely if the results are **extremely significant**.

The overall quality of the water is measured using the ‘Index of Biotic Integrity’ or** IBI**.** The highest quality of water will have an IBI score of 100, whereas a score of 0 represents the lowest water quality. **Some reservoirs are also ‘treatment sites’ where the water is treated using chemicals to remove impurities * before* storage in the reservoir. The other ‘non treatment’ reservoirs use chemicals

*the water has left the reservoir.*

**after**The data collected for the study is shown below for all **89** reservoirs. A ‘**T**’ next to the data indicates that the sample was taken from a ‘**treatment site’**. The water samples were all taken at a standard mean depth of 3 meters however the data collector reported that a small batch of measurements were taken before **a fault was detected** (and resolved) in the depth gauge. The fault led to some readings being taken at a mean depth of 1 meter. **Your analysis will need to take account of any possible anomalies and state their possible impact on any conclusions.**

Your task is to **analyse** the study data and write your recommendations for the Director of Water Supplies in a short, non-technical report (approx. **600 words** only). Your results should be clear enough to allow the director to make the **best decision**. Some examples of possible decisions the director __might__ make are:

· Ask for a more detailed study

· Start new construction

· Change water treatment policies

· Do nothing

Whatever your recommendations are – __they must be clearly supported__ by your calculations using the supplied study data.

You should include a **full numerical summary** of the data in the study. You should include an explanation of the factors, treatments and any lurking variables which may be present in the pilot study and any future research. You should highlight any possible errors in measurement, data anomalies or outliers and __describe their effect on your conclusions.__ You should describe any correlation between the variables, if present.

You should summarize any findings in the form of **clear****, ****supported** recommendations that allow the Director to *decide* policy for the future.

**Assessment Approach **

Any calculations must only use the methods and techniques described to you on this course.

You *must* produce a *maximum* of 2 graphical representations of the given data from the following options:

1. Histogram

2. Box Plot

3. Modified Box Plot

4. Cumulative Relative Frequency Curve

[For example, you may choose: 1 Box Plot and 1 CRF – or – 1 Modified Box Plot and 1 Histogram but no more than 2 in total]

You *must also* conduct the following two tests (with the given limits in brackets).

1. Linear Regression (with a *maximum* of 2 correlations, 2 scatter plots and 2 residual plots)

2. 2 Sample Confidence Interval (with a *maximum* of 2 [2 sample] intervals)(two-sample intervals)

· Note: depending on circumstance or purpose, there is no ‘best’ confidence level, your choice of confidence level must be justified based on *your* purpose.

You should comment on the validity and meaning of any test you conduct *in the context of the test result.*

All calculations and statistical tests must be conducted using Microsoft Excel. __Use of any other software is not permitted__.

After submission, any spreadsheets you use (your .xls or .xlsx files) must be available to your tutor upon request however your report only requires the output graphs and tables printed within a Microsoft Word (.docx) file, in an Appendix.

__End of scenario, the Pilot study data is below:__