populations, samples and normal distribution

Question 1

what is the interquartile range?

Answer 1

3rd quartile- 1st quartile

Question 2

what is inferential statistics

Answer 2

drawing conclusions about a populatiob from a sample

Question 3

what is random selection

Answer 3

a sample represeantative of a population

Question 4

what is the parameter measure of location

Answer 4

mean, it is the top to the bottom of the bell curve (u)

Question 5

what is the parameter measure of spread

Answer 5

standard deviation

Question 6

what is the interpretable feaiture of a curve

Answer 6

the area under curve

Question 7

what is the relationship between X and P

Answer 7

X is the inverse cumulative probabilty

Question 8

what is the central limit therom

Answer 8

distribution of means approaches normal distribution as the sample size increases irrespective of the measured quanity population distribution

Question 9

when are non parametic methods used

Answer 9

when normailty condiitions are not fufiled

Question 10

when is normality assumed

Answer 10

at population level

Question 11

what is inference

Answer 11

drawing conclusions about a population by analysing a random sample

Question 12

what is random noise measured by

Answer 12

standard error

Question 13

how do you access the normailty of results

Answer 13

using a histogram or a normal probabilty plot

Question 14

what is nrandom noise measured by

Answer 14

SE

Question 15

does SD change with sample size

Answer 15

no

Question 16

does SE chand with sample size

Answer 16

yes

Question 17

what do z scores measure

Answer 17

how many SDs the above or below the data point is from the mean

Question 18

what would a positive variable and a mean < SD mean for the method

Answer 18

it woul dmake a normal distribtuin test very questionable as it implies negaive value