Unit 3 - Collecting Data

Question 1

Samples may not always represent a ———

Answer 1

population

Question 2

population

Answer 2

all the individuals we want to study

Question 3

sample

Answer 3

subset of a population used to infer about the population

Question 4

When are samples used?

Answer 4

Population is too large to study

Other limitations

Question 5

A sample can be generalized to its respective population if …

Answer 5

1- randomly selected
2- representative
3- selected specifically from that population

Question 6

confounding factors

Answer 6

Any number of factors that makes it challenging to

Question 7

observational study

Answer 7

survey without imposing treatments

can’t conclude cause & effect

Question 8

retrospective OS “looking back”

Answer 8

examining past data

Question 9

prospective OS “looking future”

Answer 9

examining data as it progresses

Question 10

experiment

Answer 10

different treatments imposed on different groups

well-designed experiment- can conclude cause & effect

Question 11

census

Answer 11

assess all individuals in a population

best way

Question 12

random sample

Answer 12

easier way

if perform correctly, can be representative of population

Question 13

simple random sample

Answer 13

every group groups have an equal chance to be selected
Assigning numbers to individuals or groups etc. and using a random number generator to generate random numbers and subsequently, random individuals

Question 14

cluster random sample

Answer 14

1- population is divided into CLUSTERS

2- SRS taken of each clusters

Question 15

stratified random sample

Answer 15

1- population divided into STRATA based on SIMILAR characteristics
2- SRS taken of each strata

Question 16

Cluster vs Stratified

Answer 16

Cluster- HETEROGENEOUS grouping

Strata- HOMOGENEOUS grouping

Question 17

Systematic random sample

Answer 17

1- RANDOM starting point

2- sample taken at fixed PERIODIC interval

Question 18

Biased

Answer 18

measure of accuracy

Question 19

Variation

Answer 19

measure of precision

Question 20

Non-random sample are ….

Answer 20

biased

Question 21

simple random sample advantages

Answer 21

unbiased/ HIGH accuracy
easy to explain
easy to perform

Question 22

SRS disadvantages

Answer 22

logistical issues

MODERATE variability

Question 23

Cluster random sample advantages

Answer 23

unbiased/ HIGH accuracy

easy to perform

Question 24

Cluster random sample disadvantages

Answer 24

homogeneous clusters result in HIGH variability

Question 25

stratified random sample advantages

Answer 25

unbiased/ HIGH accuracy

LOW variability

Question 26

stratified random sample disadvantages

Answer 26

hard to implement

Question 27

bias

Answer 27

systematic tendency to FAVOR CERTAIN RESPONSES over others

Question 28

undercoverage

Answer 28

part of population has REDUCED CHANCE of being included

Question 29

nonresponse

Answer 29

individual chosen for sample DON’T respond

Question 30

convenience samples

Answer 30

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