STA1506
ASSIGNMENT 2 2025
DUE: JULY 2025 (MEMO)
,QUESTION 1
In your own words, define and give an example of each of the following terms
when used in basic statistical computing.
(a) Value
A value is a single item of data one specific measurement or observation.
In a list of student test scores, one value might be 78 (the score for one student).
(b) Variable
A variable is a characteristic or attribute that can take on different values across
observations.
Test score” is a variable that could take values like 45, 78, 92, etc.
(c) Sample
A sample is a subset of the population that you actually observe or measure. It’s
selected so you can estimate characteristics of the larger group.
If you survey 50 out of 500 students in a school about their favorite subjects, those 50
students form your sample.
(d) Population
The population is the entire group of interest about which you want to draw conclusions.
All 500 students in the school constitute the population when you want to know every
student’s favorite subject.
, (e) Parameter
A parameter is a numerical summary (like a mean or proportion) that describes the
entire population. It is usually unknown and fixed.
The true average test score of all 500 students (say μ = 72) is a population parameter.
(f) Statistic
A statistic is a numerical summary calculated from a sample. We use it to estimate the
corresponding population parameter.
Example: The average test score of the 50 surveyed students (x̄ = 75) is a statistic.
(g) Statistical inference
Statistical inference is the process of drawing conclusions about a population based on
sample data, often including estimates and measures of uncertainty.
Using the sample mean of 75 to estimate the population mean, and calculating a
confidence interval around it to express uncertainty.
(h) Data
Data are the collection of values gathered for analysis, often organized in rows (cases)
and columns (variables).
A spreadsheet where each row is a student and columns record their test score, age,
and gender together, all those entries are the data.
ASSIGNMENT 2 2025
DUE: JULY 2025 (MEMO)
,QUESTION 1
In your own words, define and give an example of each of the following terms
when used in basic statistical computing.
(a) Value
A value is a single item of data one specific measurement or observation.
In a list of student test scores, one value might be 78 (the score for one student).
(b) Variable
A variable is a characteristic or attribute that can take on different values across
observations.
Test score” is a variable that could take values like 45, 78, 92, etc.
(c) Sample
A sample is a subset of the population that you actually observe or measure. It’s
selected so you can estimate characteristics of the larger group.
If you survey 50 out of 500 students in a school about their favorite subjects, those 50
students form your sample.
(d) Population
The population is the entire group of interest about which you want to draw conclusions.
All 500 students in the school constitute the population when you want to know every
student’s favorite subject.
, (e) Parameter
A parameter is a numerical summary (like a mean or proportion) that describes the
entire population. It is usually unknown and fixed.
The true average test score of all 500 students (say μ = 72) is a population parameter.
(f) Statistic
A statistic is a numerical summary calculated from a sample. We use it to estimate the
corresponding population parameter.
Example: The average test score of the 50 surveyed students (x̄ = 75) is a statistic.
(g) Statistical inference
Statistical inference is the process of drawing conclusions about a population based on
sample data, often including estimates and measures of uncertainty.
Using the sample mean of 75 to estimate the population mean, and calculating a
confidence interval around it to express uncertainty.
(h) Data
Data are the collection of values gathered for analysis, often organized in rows (cases)
and columns (variables).
A spreadsheet where each row is a student and columns record their test score, age,
and gender together, all those entries are the data.
