Chapter 1: Data Collection

Question 1

descriptive statistics

Answer 1

collecting, organizing, and summarizing data

Question 2

inferential statistics

Answer 2

analyze sample of data to form conclusions about larger population

Question 3

population

Answer 3

entire group to be studied

Question 4

individual

Answer 4

person or object of the population being studied

Question 5

sample

Answer 5

subset of a population being studied

Question 6

statistic

Answer 6

numerical summary of a sample

Question 7

parameter

Answer 7

numerical summary of population

Question 8

variables

Answer 8

particular characteristics of individuals in the population

Question 9

qualitative (categorical) variable

Answer 9

classification of an individual based on attribute or characteristic

Question 10

quantitative (numerical) variable

Answer 10

numerical measure of individuals

Question 11

discrete variable

Answer 11

quantitative variable where values obtained by counting

Question 12

continuous variable

Answer 12

quantitative variable that can take up infinitely many and uncountable values

Question 13

level of measurement

Answer 13

way that a set of data is measured

Question 14

nominal

Answer 14

labeling variables without quantitative value (ex: gender)

Question 15

ordinal

Answer 15

order is important but difference in measurements won’t make sense (ex: letter grades)

Question 16

interval

Answer 16

numeric scale with order and exact difference (ex: temerature)

Question 17

ratio

Answer 17

like interval, but has 0 and ratios can be calculated (ex: number of days studied in a week)

Question 18

random sampling

Answer 18

using chance to select individuals from a population for a sample

Question 19

simple random sampling

Answer 19

every sample size n has an eqal chance of being chosen from the population N

Question 20

with replacement

Answer 20

once an individual is picked, individual goes back into population and can be equally picked again

Question 21

convenience sampling

Answer 21

sample is picked by availiability

Question 22

stratified sample

Answer 22

sample taken by seperating population into different groups (strata) and obtaining a simple random sample of each stratum

Question 23

How does one select a stratified sample?

Answer 23

1. define the groups based on similarites
2. conduct simple random sample of each group
3. use seed that is different for each group

Question 24

systematic sample

Answer 24

sample obtained by selecting every kth individual from the population, where the first individual p is randomly selected between 0

Question 25

How does one conduct a systematic sample?

Answer 25

1. determine population size N
2. determine desired sample size n
3. Compute N/n and round down to find p
4. randomly select number btwn 1 and k for p
5. the sample consists of starting number p, and add k each time to find the next

Question 26

cluster sample

Answer 26

sample obtained by creating different clusters and randomly selecting the clusters but choosing all individuals in the cluster as the sample

Question 27

How does one conduct a cluster sample?

Answer 27

1. decide hown to difide population into clusters
2. randomly select which clusters to survey
3. survey all individuals in chosen clusters

Question 28

bias

Answer 28

when the results of sample not representative of sample

Question 29

sampling bias

Answer 29

when the techniques used to select individuals favors one part of population over another

Question 30

nonresponse bias

Answer 30

individuals selected for sample don’t respond and therefore don’t contribute their differing opinions

Question 31

response bias

Answer 31

answers on survey don’t accurately reflect true feeling of individual