AGR 3204
Experimental Designs & Research Methods in Biological Sciences
Worksheet III 2023
Name:
USI:
Instructions:
Answer all five questions.
Insert your answers immediately below each question.
DO NOUUSE pdf FORMAT TO SUBMIT YOUR ANSWER PAPERS
Questions
1. The Guyana Water Inc. has received hundreds of complaints from residents of several
villages in East and West Canje, concerning the quality of water delivered to them. GWI
wishes to ascertain (a) the veracity of claims made in the complaints, (b) the possible
reasons for the problems highlighted and (c) possible solutions to identified problems.
For these purposes, management has decided to undertake a survey.
(a) Choose an appropriate sampling method and justify your choice.
-
Probability sampling : involves random selection, allowing you to make strong
statistical inferences about the whole group. The type of probability sampling that
would be an appropriate sampling method is Stratified sampling - involves dividing
the population into subpopulations that may differ in important ways. It allows you
draw more precise conclusions by ensuring that every subgroup is properly
represented in the sample. Management can divide East and West Canje area into
stratas and collect water sample from each strata consisting in about 25 different
samples from each strata. This can help accurately determine the water quality and
also able to locate the possible areas within East and West Canje that are affected
with low water quality
(b) State the objectives of the proposed activity.
- To determine the water quality of the water delivered to the residents of East and
West Canje (pH, turbidity, etc)
- To determine if the water being delivered is above or below recommend Water
Quality for tap water
- To determine possible causes of the drop in water quality if the claims are factual
-
To establish possible preventative measures for the dropping or potential
dropping of water quality in East and West Canjie
(c) Suggest an appropriate sample size.
25 samples from each of the villages from East and West Canjie
(d) Justify your answer at (c)
The more samples there is the more accurate and precise the findings will be and
doing 25 samples within each village will help management to better understand the
cause or area of the drop in water quality if any exist
2. You are given exactly ten (10) minutes for the oral presentation of your Final Year
Project proposal. Taking guidance from the various sections of the proposal, set out a
schedule allocating appropriate time to each section.
1. Introduction (2 mins)
2. Literature Review (2mins)
3. Research Question(s) (1 min)
4. Objectives & Hypotheses (1 min)
5. Methodology (2 mins)
6. Budget (1 min)
7. Schedule of Activities & References (1 min)
3. The simple bar diagram and the pie chart may be used to illustrate similar types of data.
With the aid of two examples, show how one of these two figures may be preferred over
the other.
Bar graphs have a wide range of uses, many more than pie charts. The flexibility of a bar
chart allows you to use it to present percentages, totals, counts and many other things,
provided you can find a reasonable way to group the contents of the x-axis, whether by
category or by time.
Examples of choosing Bar graphs instead of Pie chart
For example, if you were showing the results for a class president election in school, each
candidate would have his or her own bar on the x-axis and the values on the y-axis would
be number of votes the candidate received.
If you were showing the revenues of various companies, you could use a bar chart with a
bar for each company and the length corresponding to its revenue in dollars.
Examples of choosing pie charts instead of the bar graph
For example, a pie chart works well for displaying a breakdown of sales for each item for
a business. Your total sales are the whole “pie,” but the slices tell you how much each
product contributes. You might sell fruit, for example, and a pie chart of the different
types of fruit you sell shows that apples make up the largest chunk of your sales,
followed by bananas.
4. The ANOVA table below represents analysis of data from a field study of the response of
a certain crop’s varieties to field conditions.
Sources of variation
df
SS
MS
F
Rows
4
74.49
18.62
˂1
Columns
4
44.17
11.04
˂1
Varieties
4
947.14
236.78
8.87
Error
12
320.09
26.66
Total
24
1385.91
(a) What type of Latin Square Design was used here?
5x5 LSD plan
(b) Write an appropriate null hypothesis for the study.
There is no effect of different field conditions on a certain crop’s response
(growth)
(c) Was the use of LSD justified?
No
(d) If the answer to the above is no state why not.
Since F is not less than 0.05 ….F <0.05
(e) Suggest an alternative design and justify your choice.
Multiple – Factor design – this can be used because multiple factors of conditions can
be considered
5. The figure below was presented in a final year project report. Find five mistakes
/omissions that need to be rectified.
Mistakes
- Different colours should have been used for each treatment
- Instead of T1 , 1 could have been used since the x axis already states the variable
- The bars should have been spread out a bit more for visual purposes
- A key with the scale should have been shown
- Grid lines should have beein used to illustrate the number of branches properly for
audience visual purposes