Chapter 1 - Class 1

Question 1

What are statistics?

Answer 1

when were collecting, analyzing, and drawing conclusions

Question 2

What do statistics assign a degree of?

Answer 2

a degree of certainty

Question 3

What does statistics quantify the level of?

Answer 3

uncertainty from range and probability

Question 4

What are the two categories of statistics?

Answer 4

the two categories of statistics are descriptive and inferential stats

Question 5

What are descriptive stats?

Answer 5

organizing and summarizing numbers using charts, numbers, graphs with already known data

Question 6

What is inferential statistics?

Answer 6

making conclusions based on a population

Question 7

What techniques do inferential stats use?

Answer 7

estimation (degree of uncertainty) and hypothesis testing

Question 8

What does descriptive stats illustrate?

Answer 8

average and variation

Question 9

What is a statistical population?

Answer 9

all individuals for which we have an interest concerning some property

Question 10

What is a census?

Answer 10

using all people in a population and surveying/testing them in some way (ACCURATE)

Question 11

What is a sample?

Answer 11

involves a portion of the population since true values of population characteristics are usually unknown

Question 12

What is random sampling?

Answer 12

to avoid bias, the population should represent our hypothesis and has an equal chance of being selected and that selection of each individual has no effect on the chance of selecting another individual (rock paper scissors, we are effected by the outcome of our choice and influenced by it for the next move)

Question 13

What is precision?

Answer 13

how close you are to your other numbers

Question 14

What is accuracy?

Answer 14

how close you are to the true value

Question 15

What does it mean for a sample to be biased during accuracy testing?

Answer 15

when the sample produces too high or too low of values to the correct value

Question 16

What is a stratified random sample?

Answer 16

taking entire population and breaking into common subpopulations and randomly picking/sampling from each subpopulation

Question 17

What is the method to random sampling?

Answer 17

1) assign a number to the population
2) decide how many units/sample will be collected (n)
3) use a method to generate random integers from 1 to n
4) sample the n amount of units chosen and apply a characteristic

Question 18

Where are stratified random samples used often?

Answer 18

in medicine

Question 19

What are the two types of poor sampling designs?

Answer 19

convenience samples and voluntary responses

Question 20

What are convenience samples?

Answer 20

sample individuals that are easy to reach and omit those that are difficult

Question 21

What are voluntary samples?

Answer 21

relies on the decisions of volunteers is also commonly biased as they might represent specific social groups (ex: giving money as an incentive but only poor people come)

Question 22

What is an independent population?

Answer 22

the population has no correlation to another population