In: Statistics and Probability
1. What do we mean by the direction of the linear relationship between two variables?
Group of answer choices
Direction is used to describe possible directions when arrows are placed on the points
Direction is used to describe if the points are pointing North or South
Direction is used to describe if the points are pointing east or west
Direction describes if the points are rising or falling as you go from left to right
2. Describe the strength and direction of the linear relationship between two variables in which the value of r is between 0.7 and 1
Group of answer choices
strong and moderate
strong and positive
strong and negative
weak and positive
3. True or False: when two variables are strongly correlated, the independent variable causes the dependent variable to behave as observed
Group of answer choices
true
false
4. The regression line can be used to predict the value of the independent variable (x).
Group of answer choices
False
True
1) True option :- Direction describes if the points are rising or falling as you go from left to right
The Direction of a Relationship :-
The correlation measure tells us about the direction of the relationship between the two variables. The direction can be positive or negative.
In the example above, GPA and MathSAT are positively related. As GPA (or MathSAT) increases, the other variable also tends to increase.
The direction of the relationship between two variables is identified by the sign of the correlation coefficient for the variables. Postive relationships have a "plus" sign, whereas negative relationships have a "minus" sign.
2) True option:- strong and positive
Generally, a value of r greater than 0.7 is considered a strong correlation. Anything between 0.5 and 0.7 is a moderate correlation, and anything less than 0.4 is considered a weak or no correlation.
Values between 0.7 and 1.0 (-0.7 and -1.0) indicate a strong positive (negative) linear relationship via a firm linear rule.
3) True because an independent variable is the variable that is changed or controlled in a scientific experiment to test the effects on thedependent variable. A dependent variable is the variable being tested and measured in a scientific experiment. The dependent variable is 'dependent' on the independent variable.
The relationship between two variables is generally considered strong when their r value is larger than 0.7. The correlation r measures the strength of the linear relationship between two quantitative variables.
4) False because the goal in regression analysis is to create a mathematical model that can be used to predict the values of a dependent variable based upon the values of an independent variable. In other words, we use the model to predict the value of Y when we know the value of X. (The dependent variable is the one to be predicted).