Data Analysis

Question 1

Density (d) formula

Answer 1

d=mass/volume (g/mL)

Question 2

Specific Gravity

Answer 2

Weight of substance: Weight of equal volume of standard (e.g. water)

Question 3

Specific Gravity formula

Answer 3

sg=weight substance (g)/ weight equal vol standard (g)

Question 4

Descriptive statistics

Answer 4

Data in numerical/ graphical form

Question 5

Inferential statistics

Answer 5

Draws conclusions about pops.

Question 6

Quantitative variable

Answer 6

Numerical values that can be averaged (e.g. height, weight)

Question 7

Categorical variable

Answer 7

Categories/ groups that=classification (e.g. eye colour)

Question 8

QV: Continuous

Answer 8

Can be measured- infinite no. values w/in range (e.g. weight)

Question 9

QV: Discrete

Answer 9

Can be categorised into classification- based on whole numbers, i.e. only finite range no.s (e.g. no. deaths)

Question 10

CV: Nominal

Answer 10

Categories do not have ordering (e.g. sexes)

Question 11

CV: Ordinal

Answer 11

Categories have logical ordering (e.g. severity disease, year levels)

Question 12

Observational study

Answer 12

Processed observed- data recorded (e.g. blood pressure)

Question 13

Randomised experimental study

Answer 13

Specific procedure whereby action=controlled + data measured (e.g. drug vs placebo)

Question 14

Placebo

Answer 14

Treatment that looks the same, but has no therapeutic effect

Question 15

Case control study

Answer 15

Study where cases w/ particular attribute (e.g. heart disease) is compared to controls who don’t

Question 16

Addition rule

Answer 16

Prob. event A or B

Question 17

Multiplication rule

Answer 17

Prob. event A and B

Question 18

Conditional prob.

Answer 18

P(B|A)- Prob B given A has occurred

Question 19

Mutually exclusive events

Answer 19

2 events that do not overlap (no common events)- prob. A and B

Question 20

Independent events

Answer 20

P(B|A)= P(B), knowing that A has already occurred (P(B)= unchanged)

Question 21

Splitting prob.

Answer 21

Law total prob.- allows prob. event B to be calculated (B=(A and B) or (Ac and B)

Question 22

Baye’s rule

Answer 22

Allows ‘turn around’ conditional prob. to occur

Question 23

Sensitivity

Answer 23

Ability of test to correctly identify people who have given disease/ disorder (the more sensitive- the fewer false -ves)

Question 24

Specificity

Answer 24

Ability of test to correctly exclude individuals who do not have given disease/disorder (the more specific- the fewer false +ves)

Question 25

Random variable

Answer 25

Assigns no. to each outcome random circumstance/ each unit in pop.

Question 26

Continuous random variable

Answer 26

Can take any value in interval/ collection intervals

Question 27

Discrete random variable DRV

Answer 27

Can take countable list of distinct values (integers)

Question 28

Prob. distribution function (Pdf)

Answer 28

Formula/ table that assigns probs. to all possible values X

Question 29

Cumulative distribution function (Cdf)

Answer 29

Formula/ table that provides cumulative probs. P(X

Question 30

Expectations for RVs

Answer 30

Expected value RV= mean value variable X in same sample space possible outcomes

Question 31

Standard deviation for DRV

Answer 31

Similar to average distance from random variable to its mean

Question 32

Binomial RV

Answer 32

No. successes (x) in n repeated trials of binomial experiment

Question 33

Continuous random variable CRV

Answer 33

Outcome can be any value in interval/ collection intervals

Question 34

Normal random variable NRV

Answer 34

Most common type CRV

Question 35

Prob. density function

Answer 35

Indicates how densely prob. of conc. about each value

Question 36

Confidence Intervals (CI)

Answer 36

Use sample data to provide interval values that is believed to cover the true/ unknown value pop. parameter

Question 37

Sampling distribution

Answer 37

Distribution possible values statistics for repeated random samples same size from pop.

Question 38

Confidence level

Answer 38

Prob. that procedure used to determine interval will provide interval that includes pop. parameter (=true value)

Question 39

t-distribution

Answer 39

t-density is similar in shape to standard normal density (symmetric around 0 + bell-shaped)