Study your flashcards anywhere!
Download the official Cram app for free >
 Shuffle
Toggle OnToggle Off
 Alphabetize
Toggle OnToggle Off
 Front First
Toggle OnToggle Off
 Both Sides
Toggle OnToggle Off
 Read
Toggle OnToggle Off
How to study your flashcards.
Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key
Up/Down arrow keys: Flip the card between the front and back.down keyup key
H key: Show hint (3rd side).h key
A key: Read text to speech.a key
20 Cards in this Set
 Front
 Back
Standard Deviation

How far away numbers on a liswt are from their average
Steps: 1. Find the Average of the list 2. Subtract the average from each entry 3. Square each Number and Devide by the number of terms 4. Square Root 

Changing SD

The SD does not change when something is added or subtracted from the list
The SD is multiplied by the number as is the list changing it by that The closer the numbers are group the 0 the smaller the deviation 

Median

Put the list of numbers in order and find the middle number


Right Hand Tail

The Average is Larger than the Median


Left Hand Tail

The Average is Smaller than the Median
Ex Death Due to Natural Causes 

Correlation Coefficient

a measure of how well trends in the predicted values follow trends in past actual values. It is a measure of how well the predicted values from a forecast model "fit" with the reallife data.
It is a number between 1 and 1; the higher is is the better the correlation Doesnt change if you add/multiply 

Slope of the SD line

SDy / SDx ( times coeficcient)


Finding the Correlation Coeficient

1. Change the x and y values to standard units
2. Multiply the x value by the corresponding y value 3. Average the Product 

RMSE

= sqrt(1r^2) * SD of Y


Expected Value (w/ Replacement)

n * average of the box


Standard Error

sqrt of n * sd of the box


SE %

SD/ sqrt n


SE for the Average

SD / sqrt n


Test of Significance

Was it due to change? Or something else involves the null and alternative


z for null questions

obsexpected/ SE sum


SE sum

n * SD


area percent between 100 and 200

A= 1/2 ( 100 * 200)


tstatistic

obsexp/ SE
SD unknown smaller sample than 25 1. First compute the SD sqrt (n/n1) 2. SD+ average is SD+/sqrt n then reg fromula 

z statistic

used in counting
obsexp/ SE sum 

box model

things must be randomly selected
