Unit 1- Intro to Statistics

Question 1

What is a census?

Answer 1

gathering data from the entire population

Question 2

What is descriptive & inferential statistics?

Answer 2

descriptive statistics= data collected from population, inferential statistics= data collected from sample to estimate information about population

Question 3

What is a parameter?

Answer 3

measure of population (greek letters), μ= population mean, σ^2=population variance, σ=population s.d.

Question 4

What is a statistic?

Answer 4

Statistic = measure of a sample (roman letters), xbar=sample mean, s^2=sample variance, s=sample s.d.

Question 5

What is a probability statement?

Answer 5

Probability statement: used to estimate the

level of confidence in the result of the process

Question 6

What are the 4 common levels of data measurement?

Answer 6

Nominal, Ordinal, Interval & Ratio

Question 7

What is grouped & ungrouped data?

Answer 7

Ungrouped data = raw data (untouched), Grouped data = organised into frequency distributions

Question 8

What is a frequency distribution?

Answer 8

summary of data presented in the
form of class intervals and frequencies.

Question 9

What is relative frequency?

Answer 9

the proportion of the total frequency
that is in any given class interval in a frequency distribution. (probability of occurrence) (frequency in class interval/total frequency)

Question 10

What is cumulative frequency?

Answer 10

the running total of frequencies
through the classes of a frequency distribution. (frequency in class interval + cumulative frequency in previous class interval)