Module B2 Sessions 4 & 5
essions 4 & 5: Practical 1 - Produce good
tables using tallies and further calculations in
Excel
Activity 2: Frequency tables explained by Cast.
3. Open CAST for SADC: Basic Level
4. Go to Section 2.1 Frequency tables. You should see there are 6 pages in this
section
5. Go to the first page, Page 2- 1 – 1 (Called Categorical Data – Frequency tables –
Frequency tables).
6. Read through this page, and complete all the interactive exercises.
7. Pay close attention to the description of the “Rice Survey”. These data are used
repeatedly in this Module.
8. What is major difference between the two data layouts on this page? In surveys that
you work with, are you more likely to see the first layout or the second one? Briefly
explain.
9. Read the next page, 2.1.2, called Proportions and percentages. Complete the table
below to explain how the proportions and percentages are calculated:
Level
Count
Explanation
(thousands)
Piped water
1093
Proportion = count/total = 1093/4805 =0.227. You can see
it is about a quarter. Percentage = 100*0.227 = 22.7%
Protected
well
Protected
spring
Total
protected
SADC Course in Statistics
Sum of these three levels. The proportion is therefore …
Module B2 Sessions 4&5 – Page 1
Module B2 Sessions 4 & 5
Activity 3: Calculating proportions and percentages for the Rice Survey
data (described in Activity 2 by Cast).
1. The data from page 2.1.1 in CAST are shown below
2. Do the tally “by hand” from this table, and hence give the counts.
3. Complete the last 2 columns to give the proportions and percentages (using
a calculator if necessary).
Data
Variety
Tally
Count
Proportion
Percentage
New
Old
Trad
Total
-------
Check that your frequencies are the same as those you found in CAST.
4. Open the Rice survey workbook in Excel
5. Insert a new worksheet into the Excel file, and enter the summary
information from the table above, so it looks like this:
6. Use Excel to calculate the frequency totals in cell B5 and to calculate the
proportions and percentages. The values Excel calculates are in the table
above, but you should use Excel to get them, and not type them in. (If you
are unsure how to do this efficiently then please watch the demonstration
called “Proportions and percentages”). Tidy the numbers in the resulting
table, so it looks like the table below.
SADC Course in Statistics
Module B2 Sessions 4&5 – Page 2
Module B2 Sessions 4 & 5
7. Go to the sheet called rice data in the same workbook. Repeat the hand
exercise for the Village column to complete the table below (i.e. tally or
count the numbers, and then calculate the proportions and percentage of
farmers in each of the 4 villages).
Village
Tally count
Total
--------------------
Frequency
Proportion
Percentage
8. Now, on a new Excel sheet, repeat the calculations above, to produce the
proportions and percentages in Excel. The second half of the
demonstration shows one way to do this.
SADC Course in Statistics
Module B2 Sessions 4&5 – Page 3
Module B2 Sessions 4 & 5
Activity 4: Calculating frequencies and proportions of specific subsets using
Tanzania drinking water frequency table.
Page 2.1.2 in CAST showed a table of counts and percentages from the Tanzania
agriculture survey. The questions that led to this table were as follows:
The table for the dry season was as follows:
1. Type the counts from this table (rounding to the nearest thousand) into a
new sheet in Excel.
SADC Course in Statistics
Module B2 Sessions 4&5 – Page 4
Module B2 Sessions 4 & 5
2. Use Excel to get the proportions and percentages, using the same methods
as for the rice survey above. Give your answers to 3 decimal places for the
proportions and 1 decimal place for the percentage.
3. Either “by hand” or using Excel, answer the following questions:
a. How many households have access to reasonably safe water
sources (assume piped water is as safe as the protected sources)?
b. What percentages of households do not get piped water?
c. What proportion of households use surface water?
d. From the households which use well water, what percentage
has access to protected wells?
SADC Course in Statistics
Module B2 Sessions 4&5 – Page 5
Module B2 Sessions 4 & 5
Activity 5: Interpreting results from the Survey on Principles of Good
Statistics.
Open the dataset Fundamental principals of Statistics. The data gives the total number
(and percentages) of countries that responded to the question on overall
implementation of principles of official statistics in a survey carried out by United
Nations Statistics Division (UNSD).
1. Consider the first principle, namely “Relevance, impartiality and equal access to
data”.
If you were selected to respond for your country, how would you respond?
In my country, overall this principle is ……………. implemented?
2. Create a copy of the sheet “from data” (using Edit – Move or Copy Sheet) -make
sure you tick ‘create a copy’ (If you are unsure of how to do this refer to the
demonstration “Protecting and Copying in Excel”).
a. Copy the titles (rows 5-13) from Col A into Col I.
b. In Col J, for each principle, give the percentage of countries that have either
fully or largely implemented it (e.g. for principle 1, this will be (B5+C5)/F5
= 0.89)
c. In Col K, give the converse, i.e. the percentage of countries that have
neither fully nor largely implemented the principles.
3. From the table you have constructed answer each question that is possible. If no
answer is possible, explain why not and outline the table you would need to be able to
answer it.
a. The percentage of countries that have implemented Principle 1, either fully
or largely.
b. The percentage of countries that not implemented Principle 2, (either fully
or largely).
SADC Course in Statistics
Module B2 Sessions 4&5 – Page 6
Module B2 Sessions 4 & 5
c. The percentage of countries that have fully or largely implemented both
Principle 1 and Principle 2.
d. The percentage of countries that have neither implemented Principle 1 nor
Principle 2.
SADC Course in Statistics
Module B2 Sessions 4&5 – Page 7