STA1506 Assignment 04 – Solutions
Unique Number: 635796
Student: [Your Name Here] – Student No: [Your Student No Here]
QUESTION 1(a)
Excel formulas for data in Z3:Z32:
Mean =AVERAGE(Z3:Z32)
Standard deviation (sample) =STDEV.S(Z3:Z32)
First quartile (Q1) =QUARTILE.INC(Z3:Z32,1)
Median =MEDIAN(Z3:Z32)
Coefficient of Variation (%) =STDEV.S(Z3:Z32)/AVERAGE(Z3:Z32)*100
QUESTION 1(b)
Corrected dataset entered in Excel (STA1506_Marks_corrected.csv attached).
Statistic Value
n 52
mean 68.63461538461539
median 71.5
mode [64.0, 53.0, 74.0, 91.0, 84.0, 85.0]
min 3.0
max 95.0
range 92.0
std_sample 20.512099581976855
coefficient_of_variation_% 29.885939430170815
Q1 54.75
Q3 85.0
IQR 30.25
SIQR 15.125
(iii) ToolPak Descriptive Stats: attach Excel output.
(iv) Data rearranged into single column A: see Excel output.
(v) The single-column version is more representative (n=52).
(vi) Compare st.dev. across columns; in single-column version st.dev ≈ 21.15.
(vii) Admission at 85%: 25% of students qualify (13/52). Suggested realistic cutoff ~70%.
QUESTION 1(c)
Histogram and boxplot of 50 electricity costs.
Unique Number: 635796
Student: [Your Name Here] – Student No: [Your Student No Here]
QUESTION 1(a)
Excel formulas for data in Z3:Z32:
Mean =AVERAGE(Z3:Z32)
Standard deviation (sample) =STDEV.S(Z3:Z32)
First quartile (Q1) =QUARTILE.INC(Z3:Z32,1)
Median =MEDIAN(Z3:Z32)
Coefficient of Variation (%) =STDEV.S(Z3:Z32)/AVERAGE(Z3:Z32)*100
QUESTION 1(b)
Corrected dataset entered in Excel (STA1506_Marks_corrected.csv attached).
Statistic Value
n 52
mean 68.63461538461539
median 71.5
mode [64.0, 53.0, 74.0, 91.0, 84.0, 85.0]
min 3.0
max 95.0
range 92.0
std_sample 20.512099581976855
coefficient_of_variation_% 29.885939430170815
Q1 54.75
Q3 85.0
IQR 30.25
SIQR 15.125
(iii) ToolPak Descriptive Stats: attach Excel output.
(iv) Data rearranged into single column A: see Excel output.
(v) The single-column version is more representative (n=52).
(vi) Compare st.dev. across columns; in single-column version st.dev ≈ 21.15.
(vii) Admission at 85%: 25% of students qualify (13/52). Suggested realistic cutoff ~70%.
QUESTION 1(c)
Histogram and boxplot of 50 electricity costs.