Positive correlation - Answers As one variable increases, the other variable increases
Negative correlation - Answers As one variable increases, the other decreases
A point on the scatter plot represents how many values? - Answers 2 (X and Y)
Relationship between linear and scatter plot diagrams? - Answers The regression line is the best-fitting
line through a scatter plot
If you see the notation (E X)(E Y) what should you do? - Answers First sum the Xs, then sum the Ys, then
multiply the sums
If you see the notation E XY what should you do? - Answers First multiply each X by its partner Y, then
sum the results
If there is a relationship between "amount of coffee consumed" and "nervousness", then as the amount
of coffee consumed increases, the amount of nervousness... - Answers Changes in some consistent,
predictable manner
What does a correlation coefficient do? - Answers It quantifies the pattern in a relationship
In an experimental design _________, whereas in a correlational design ________. - Answers
researchers assign each person an X score and then measure the score on the Y variable;
researchers measure scores on variables that a participant has already experienced
If we calculate a correlation coefficient and we find that there is a relationship between the two
variables, we... - Answers cannot conclude that changes in one variable cause changes in the other
variable
Using correlation design, a researcher found a relationship between the healthiness of one's heart and
the amount of fish oil in one's diet. The researcher should conclude that... - Answers although a
relationship exists, one cannot infer that changes in one variable are causing changes in another variable
Professor Johnston and strong correlation between neckties and strokes; claims wearing neckties causes
strokes. What error has he made? - Answers Professor Johnston is drawing a causal conclusion from
correlational findings
In a correlational analysis, N stands for the - Answers total number of pairs of scores
We should do a scatterplot of the data when we compute a correlation because the scatterplot allows us
to - Answers see the nature of the relationship between the two variables
when plotting correlational data, the appropriate graph to use is the - Answers scatterplot!
, To know whether theres a relationship btwn two variables, you draw a line around the outer edges of a
scatterplot. You can tell there is no relationship when - Answers the scatterplot is either circular or
elliptical, with the ellipse being parallel to the X axis
The best-fitting line through a scatterplot is known as the - Answers regression line
what type of relationship does a horizontal line parallel to the X axis represent? - Answers No
relationship
What kind of relationship is represented by a line slanting downward from left to right? - Answers A
negative relationship
"the self-confidence of a group of students is positively correlated with their chances of getting through
the course"- what does this statement mean? - Answers The chances of passing the course tend to
increase as the self-confidence scores of the students increase
In general, a positive correlation means that as the values of one variable ______, there is a tendency
for the values of the other variable to _______. - Answers Increase; increase
In a linear relationship, as the X scores increase, the Y scores change... - Answers in only one direction
"the bigger they are, the harder they fall" describes... - Answers A positive linear correlation
"The more you save, the less you spend" describes... - Answers a negative linear correlation
Prof. Miller found correlation btwn a "need for affiliation" and # of hours spent watching television is
-.69; he should conclude... - Answers As we observe people with higher and higher need for affiliation,
we see a tendency for those people to spend less and less time watching television
In a non-linear or curvilinear relationship, as the X scores change, the Y scores... - Answers Change
consistently, but in more than one direction
A nonlinear correlation looks like what? - Answers Low to high and back to low, like a rainbow!
The strength of a relationship is indicated by the extent to which ________ paired with each individual
value of the _________ variable. - Answers One value of the Y variable is;
X
Which of the following r-values indicates the strongest relationship between two variables? - Answers -
0.89
Which of the following r-values indicates the weakest relationship between two variables? - Answers
+0.03
which relationship is stronger, r = +0.62 or r = -0.62? - Answers There is no difference in the strength of
the two relationships