Flashcards in Statistics Formula Deck (17):

1

## What is the formula to work out the value of k in a histogram?

### k = (area of bar)/freq

2

## What is the formula for linear interpolation?

###
linear interpolation = Lower bound of class + (freq into class/freq)Class width

3

## What is the formula for frequency density in a histogram?

### freq density = freq/class width

4

## What is the formula for variance in discrete data?

###
((∑x^2/n) - (∑x/n)^2))

5

## What is the formula for Standard deviation?

### √(variance)

6

## What is the formula to work out IQR?

### Q3 - Q1

7

## What is the formula to work out Q1?

### n/4

8

## What is the formula to work out Q3?

### 3n/4

9

## What is the formula to work out the area of a bar in a histogram?

### Area of bar = k x freq

10

## What is the formula to work out frequency in a histogram?

### Freq = freq density x class width

11

## What is the formula in terms of quartiles to show that there is a positive skewness?

### Q2 - Q1 < Q3 - Q2

12

## What is the formula in terms of quartiles to show that there is a symmetrical skewness?

### Q2 - Q1 = Q3 - Q2

13

## What is the formula in terms of quartiles to show that there is a negative skewness?

### Q2 - Q1 > Q3 - Q2

14

## What is the addition rule in probability?

### P(AuB) = P(A) + P(B) - P(AnB)

15

## What is the multiplication rule in probability?

###
P(AnB) = P(AIB) x P(B)

or

P(AnB) = P(BIA) x P(A)

16

## What is the formula for variance in discrete random variables?

### Var = (EX^2) - ((EX)^2))

17