4.1
What is the correlation coefficient?
a number between -1 and 1, calculated so as to represent the linear dependents of two variables.
What is the slope?
The amount by which y increases when x increases.
How can an an observation be classified as an influential observation?
If the removal of the observation has a large impact on the slope or intercept of the least squares regression line.
What is standard deviation?
a number used to tell how measurements for a group are spread out from the average, or expected value.
What is the probability that a dice lands on a 4 in one roll.
1/6
What is correlation?
a mutual relationship or connection between two or more things.
What is the least squares regression line?
This is the line that minimizes the sum of squared deviations.
What is the coefficient of determination?
the proportion of variability in y that can be attributed to an approximate linear relationship between x and y.
What does a low standard deviation mean?
It means that most of the numbers are very close to the average.
What is the probability that you roll two 3's in two throws?
1/36
What does the correlation coefficient do?
Measures the strength of a linear relationship.
What is a dependent variable?
a variable whose value depends on that of another.
what are residuals?
the vertical deviation of a point in the scatterplot from the least squares regression line.
What does a high standard deviation tell you?
It means that the numbers are very spread out.
A card is drawn from a pack of 52 cards. The probability of getting a queen of clubs or a king of hearts is?
1/26
What is the least squares regression line?
THE LINE THAT MINIMIZES THE SUM OF SQUARE DEVIATIONS.
What is the line that minimizes the sum of squared deviations?
The least squares regression line.
what determines if a residual is positive or negative?
a point above the line is positive, while a point below is negative.
What is step one in linear regression analysis?
Summarize the data graphically by construction a scatterplot.
A bag contains 6 black and 8 white balls. One ball is drawn at random. What is the probability that the ball drawn is white?
8/14= 4/7
what is regression?
a measure of the relation between the mean value of one variable and corresponding values of other variables.
What is regression analysis used for?
it is a technique used to find the relations between two or more variables.
what are predicted values?
result from substituting each x value into the regression line.
What is step 3 in a linear regression analysis?
Find the equation of the least squares regression line.
One card is drawn at random from a pack of 52 cards. What is the probability that the card draw is a face card? (Jack, Queen, and King only)
12/52= 3/13