STRAIGHTERLINE INTRODUCTION TO
STATISTICS EXAM STUDY GUIDE 2026 FULL
QUESTIONS AND SOLUTIONS GRADED A+
⩥ What is *inferential statistics*? Answer: Inferential Statistics is the
branch of statistics concerned with methods for drawing conclusions
about a population by examining a *sample* of the population.
Inferential Statistics is also concerned with measuring the reliability of
such conclusions.
Inferential Statistics
♦ Drawing conclusions from a sample of a population
♦ Measuring the reliability of conclusions drawn from samples.
⩥ What is a *population*? Answer: In statistics, a population is the
collection of all items (or people) under consideration in a statistical
study.
⩥ What is a *sample*? Answer: In statistics, a sample is the subset of
the population from which information is obtained.
, Samples are usually taken because the full population cannot be assessed
for practical reasons.
⩥ What is an *observational study*? Answer: An observational study is
an assessment of data taken from real life. These studies do not include
any controls.
Example:
A doctor finds 113 cases of prostate cancer among 22,000 men who had
a vasectomy. This shows a 60% increased risk from the general
population.
Note:
Observational studies can ONLY demonstrate correlation!
Observational studies can NEVER demonstrate causation.
⩥ What is a *designed experiment*? Answer: Exactly what it sounds
like.
Researchers impose controls.
Designed experiments CAN help establish causation.
⩥ --- 1.2 Data Classification --- Answer:
STATISTICS EXAM STUDY GUIDE 2026 FULL
QUESTIONS AND SOLUTIONS GRADED A+
⩥ What is *inferential statistics*? Answer: Inferential Statistics is the
branch of statistics concerned with methods for drawing conclusions
about a population by examining a *sample* of the population.
Inferential Statistics is also concerned with measuring the reliability of
such conclusions.
Inferential Statistics
♦ Drawing conclusions from a sample of a population
♦ Measuring the reliability of conclusions drawn from samples.
⩥ What is a *population*? Answer: In statistics, a population is the
collection of all items (or people) under consideration in a statistical
study.
⩥ What is a *sample*? Answer: In statistics, a sample is the subset of
the population from which information is obtained.
, Samples are usually taken because the full population cannot be assessed
for practical reasons.
⩥ What is an *observational study*? Answer: An observational study is
an assessment of data taken from real life. These studies do not include
any controls.
Example:
A doctor finds 113 cases of prostate cancer among 22,000 men who had
a vasectomy. This shows a 60% increased risk from the general
population.
Note:
Observational studies can ONLY demonstrate correlation!
Observational studies can NEVER demonstrate causation.
⩥ What is a *designed experiment*? Answer: Exactly what it sounds
like.
Researchers impose controls.
Designed experiments CAN help establish causation.
⩥ --- 1.2 Data Classification --- Answer:
