further stats 3

Question 1

how can you tell if data is bivariate

Answer 1

if scatter graph is rougly eliptical

Question 2

pmcc

Answer 2

summary statistics - equations
table - calculator y=a+bx - variable calc
gives r
null and alternate include p
Ho : p = 1
H1: p > 1
define p population correlation coefficent
r > cv reject Ho
sufficent evidence to suggest
assertive conclusion

Question 3

spearmans rank

Answer 3

dosent have to be eliptical
-1 perfect negative 1 perfect positive
random
Ho : assosiation …. in the underlying population
rank data if two same add and divide by two
put rank in calculator
rs > cv reject h0

Question 4

which is better pmcc or spearmans

Answer 4

pmcc as it uses actual values

Question 5

regression lines

Answer 5

y on x y = a + bx. a = ymean -bxmean
x on y x = a + by a = xmean - bymean

Question 6

choosing on which

Answer 6

y on x calcucate y with a given x
x on y calculate x with a given y
random on random - either
non random on random - y on x only

Question 7

residual

Answer 7

distance between regression line and each point
y on x - vertical
x on y - horizontal
oberved value - value from regression line