Flashcards in Chapter 2 Deck (24):

1

## The ___ _____ of a distribution is the value with āpā percent of the observations less than it

### Pth percentile

2

## Another name for a cumulative frequency graph is an ______

### Ogive

3

## __ is equal to the 25th percentile

### Q1

4

## The median is equal to the ____ percentile

### 50th

5

## __ is equal to the 75th percentile

### Q3

6

## _____________ is the formula for a z-score

### (X-mean)/standard deviation

7

## In a histogram, our eyes respond to the areas of the bars. These bars represent _______ of the observations

### Proportions

8

## A density curve has a total area under the curve of ___. Ares under the curve represent _______ of the observations

### Areas, proportions

9

## ______, are not described by the density curve. No real set of data is described.

### Outliers

10

## The ______ of the density curve is the equal areas point-the point with 1/2 of the data to the left and 1/2 of the data to the right.

### Median

11

## The _____ of the density curve is the point at which the curve would balance if are of solid material

### Mean

12

## The means and the median of a symmetric density curve are _____

### Equal

13

## The mean of a skewed curve is pulled away from the median in the direction of a ___ ____

### Long tail

14

## The density curve is an ____ set of data, so we must distinguish its mean and standard deviation from that of an actual set of data

### Idealized

15

## We use ___ and ___ for an actual set of data

### X (bar over) and Sx

16

## We use ___ for mean and ____ for standard deviation for an idealized set of data

### Mu and sigma

17

## ____ _____ are density curves that are symmetric, single peaked, and bell shaped

### Normal curve

18

## The standard deviation controls the ____ of a normal curve

### Spread

19

## ____ of the data falls between one standard deviation of the mean

### 68%

20

## ____ of the data falls between two standard deviations of the mean

### 95%

21

## ____ of the data falls between three standard deviations of the data

### 99.7%

22

## The normal curve is described by _____

### N(mu, sigma)

23

## Adding and subtracting the same number to each observation adds it subtracts from the ___ __ _____, but not from _____ __ _______

### Center or location, spread or shape

24