Search
Browse
Create
Log in
Sign up
Log in
Sign up
MATH163 Final
STUDY
Flashcards
Learn
Write
Spell
Test
PLAY
Match
Gravity
Terms in this set (36)
In analysis of a two variable data set, you find that r is negative. This means that the slope of the least squares regression line must also be negative.
true
If a distribution is symmetric, then it must be a normal distribution.
false
The correlation between two variables is resistant to outliers
false
As data values become closer to each other and the mean, the value of the standard deviation increases
false
If you change the units of the explanatory variable, the equation of the least squares regression line will stay the same
false
If you flip explanatory and response variable, the least squares regression line will remain the same
false
If the correlation coefficient for two variables is very close to zero, there is no relationship between the variables
false
Strong association between two variables gives good evidence that changes in one variable causes changes in the other variable
false
The mean of the residuals from least-squares regression is 0
true
The square of the correlation is the proportion of the data lying on the least squares regression line
false
The correlation r is the slope of the least-squares regression line
false
When drawing a histogram, it is important to
label the vertical axis so the reader can determine the counts in each interval
The correlation between the height and weight of children aged 6 to 9 is found to be about r=0.8. Suppose we use the height x of a child to predict the weight y of the child. We conclude
the fraction of variation in weights explained by the least squares regression line of weight on height is 0.64
The least squares regression line is the line that
makes the sum of the squares of the vertical distances of the data points from the line as small as possible
When the sample is an SRS from a population that has a N distribution the sample mean, x bar, also has a N distribution
true
Choose an SRS of size n from any population with mean u and finite standard deviation o. The central limit theorem states that the sampling distrubtion of x bar is ~N
false
If X is a binomial random variable with n=25 and p=.8 it is appropriate to use the normal approximation to the binomial to estimate probabilities associated with X
false
The law of large numbers states thta the actually observed mean outcome, x bar, must approach mean u of the population as the number of observations increases
true
If two events, A and B, are disjoint and P(B) does not equal 0, then P(A|B)=P(A)
false
With a hypothesis test, we reject the null hypothesis if the p value is large. It must be larger than the given significance level
false
In a test of statistical hypothesis, the p value tells us the probability that the null hypothesis is true
false
If two events A and B are disjoint then P(A and B)=P(A)P(B)
false
The design of a study is called _______ if it systematically favors certain outcomes
biased
A study is called ________ when neither the subjects themselves nor the medical personnel who worked with them knew which treatments any subject received
double blinded
A ________ sample consists of people who choose themselves by responding to a general appeal
voluntary
Variables are _______ when their effects on a response cannot be distinguished from each other
cofounding
You plan to construct a CI for the mean of a Normal population with known standard dev. Which of the following will reduce the size of the margin of error?
lower level of confidence, increased sample size, reduce standard dev
A p value that is significant at the 1% level is also significant at the 5% level
true
For a randomized experiment, we can say that the larger the p value the weaker the evidence against H0 provided by the data
true
The length of the CI increases as the confidence level decreases assuming that all of the other values are fixed
false
The t procedure can be used even for clearly skewed distributions when the sample is large enough
true
the 1-prop z test should only be used when np0>10 and n(1-p0)>10
true
The 2-prop z test should only be used if there are 5 or more observations in each sample
false
Example of a matched pairs design
a teacher compares the pretest and posttest scores of students
Although the difference is quite small, the effect is statistically significant. The explanation is
the sample size is very large
If X is a binomial random variable with n=25 and p=.8 it is appropriate to use the normal approximation to the binomial to estimate probabilities associated with X
false
YOU MIGHT ALSO LIKE...
Stats Stats Exam Review
30 Terms
kaylarae24
PLUS
PSY 230 Exam 2
36 Terms
Lhorn16
Psy 3600 final
27 Terms
irelandgreen
Stat 301 Purdue Exam 1 Study Set
44 Terms
BiJiesheng
OTHER SETS BY THIS CREATOR
Spanish
20 Terms
kennnnaaa
Words
79 Terms
kennnnaaa
2N vs 2S
15 Terms
kennnnaaa
LSAT: The Logical Construct
24 Terms
kennnnaaa
THIS SET IS OFTEN IN FOLDERS WITH...
stat- chapter 3
20 Terms
jackieee130
Chapter 8 practice quiz
11 Terms
cecravens
Chapter 9 Practice Quiz
14 Terms
cecravens
;