statistics

Question 1

dependent

Answer 1

value depends on the other value

Question 2

drawing scatter graphs

Answer 2

if applicable, controlled x, dependent y

Question 3

Interpolation

Answer 3

Between upper and lower bounds of data

Question 4

Extrapolation

Answer 4

Beyond given data (less reliable, relationship may not continue to be linear)

Question 5

Steep + large positive syy

Answer 5

small sxx

Question 6

shallow + positive/negative

Answer 6

small syy, large sxx

Question 7

y on x

Answer 7

y=a+bx
predicting y given x
minimise distances in x-direction

Question 8

residuals

Answer 8

distance of a point from a regression line

Question 9

Σresiduals

Answer 9

0

Question 10

r

Answer 10

-1≤ r ≤1
measure of correlation

Question 11

PMCC conditions

Answer 11

data evenly spread within an ellipse
bivariate normal distribution (2 variables, continuous, random)

Question 12

correlation

Answer 12

How close data is to a line

Question 13

PMCC

Answer 13

Testing for correlation in the population sample

Question 14

1-tailed

Answer 14

Specific correlation

Question 15

2-tailed

Answer 15

Any correlation

Question 16

first statemrnt pmcc

Answer 16

Let p (rho) be the population correlation coefficient

Question 17

null hypothesus PMCC

Answer 17

There is no correlation between x and y in a population

If defined, p = probability

Question 18

coefficient of determinant r^2

Answer 18

Proportion of the variation in y that is explained by the variation in x
How much h changes as x changes
Higher r^2 closer to line

Question 19

regression line random on non-random

Answer 19

y on x

Question 20

pmcc reject/accept

Answer 20

|r| > c.v reject H0

Question 21

residual

Answer 21

Observed - expected

Question 22

Effect sizes over PMCC

Answer 22

Large set of random bivariate data
Small non-zero PMCC, reject H0
Uninformative
Better model requires

Not always suitable for large sample because it has a low critical value

Question 23

cohen s,m,l

Answer 23

0.1,0.3,0.5

Question 24

5% significance

Answer 24

Probability of getting large PMCC where there is no PMCC in population is 5%

5% chance of incorrectly rejecting H0

Question 25

spearmans conditions

Answer 25

Non-linear Non-random on random Subjective Not roughly elliptical

Question 26

p in spearmans

Answer 26

No, not necessarily an underlying parent population

Question 27

spearmans tests for

Answer 27

Association

Question 28

Association

Answer 28

Any relationship between two variables

Question 29

null hypothesis Spearmans

Answer 29

H0: there is no association between x and y (in context)

Question 30

why should a random sample be taken for a hypothesis test

Answer 30

Proper statistical inference about the population (Assuming data from sample applies to the whole population) Important it is random or results could be skewed

Question 31

chi squared expected value

Answer 31

(Rows x col ) / total

Question 32

chi squared null hypothesis

Answer 32

H0 there is no association