Do you think you could procure a good grade in the subject of statistics? Would you like to try it? In applying statistics to a question, it is a widespread practice to start a population or process to be studied. Statisticians compile data about the entire population, which is a procedure called a census. If you want to put your knowledge to the test, get ready to take this final statistics exam.
Likely to be biased because students are less likely to be enrolled during the Summer term.
Unreliable because surveys are never as good as experiments.
Unreliable because the sample size should be at least 500
Unbiased because SRS was used to get the addresses.
31%
41%
51%
61%
Bar graph
Box plot
Stemplot
Residual plot
Scatter plot
Average dating expenses of students
All BYU Single students
The 50 students selected
All BYU students
The number of single students who spends between $20 to $50 on date
Make inferences about population parameters
Removes sampling variability
Assess cause and effect relationship
Exactly represents the population
10
40
80
100
500
A sample survey based on a simple random sample of single students.
An observational study based on a carefully selected large SRS of single students.
A comparative experiment where each single student is randomly assigned to one of two treatments
A study using single students where the males are given the treatment and the females were given the placebo.
Will be about the same
Will be greater than
Will be less than
Cannot be compared to
Cannot be computed since the balls are such different sizes
Typical distance of the Final scores from their mean was about 10 points
The Finals scores tended to center at 10 points
The range of Final scores is 10
The lowest score is 10
Jeremiah’s score is only 2.5
Only 2.5% of the players scored higher than Jeremiah
Jeremiah’s scoring is 2.5 times the average scoring in the league
Jeremiah’s scoring is 2.5 standard deviations above the average scoring in the league.
Jeremiah’s scoring is 2.5 points above the average scoring in the league
The distribution of the data is skewed to the right
The distribution of the data is skewed to the left
The distribution of the data is symmetric
"mean is less than the median" does not give any information about the shape of the distribution.
2, 3, 4, 5, 6,
301, 304, 306, 308, 311
350, 350, 350, 350, 350
888.5, 888.6, 888.7, 888.9
Changing the unit of measure for x changes the value of r.
The unit measure on r is the same as the unit of measure on y.
R is a useful measure of strength for any relationship between x and y.
Interchanging x and y in the formula leaves the sign the same but changes the value of r.
Where r is close to 1, there is a good evidence that x and y have strong positive linear relationship.
Is important enough that most people would belive it.
Has a large probability (P-value > alpha) of occurring by chance.
Has a small probability (P-value < alpha) of occurring by chance.
Is important enough to make a meaningful contribution to the relevant subject area.
Every observation is an outlier
There is no association between x and y
There is a curved association between x and y
There is a strong positive linear association between x and y
There is a strong negative linear association between x and y
Figure A
Figure B
Figure C
Figure D
None of the above.
On the average, FS increases by about 1.4 units when the Test3 score increases by 1 unit
On the average, TS increases by about 1.4 units when the Final score increases by 1 unit
The correlation between FS and TS is 1.4
The proportion of variation in FS that is explained by the regression model is 1.4
A Type I error has occurred.
Large households attract intelligent people.
A mistake was made, since correlation should be negative.
A lurking variable, such as higher socioeconomic condition, affects the association.
A
B
C
D
Mean
Statistic
Parameter
Margin of error
Know exactly what the value of the sample mean will be.
Specify the probability of obtaining each possible random sample of size n.
Use the standard normal table to compute probabilities about sample means and sample proportions from a large random samples without knowing the distribution of the population.
Determine whether the data are sampled from a population which is normally distributed.
Approximately normal with mean=16 and a standard deviation of 0.5
Approximately normal with mean=16 and a standard deviation of 5
Approximately normal with mean=sample mean and a standard deviation of 0.5
Approximately left skewed with mean=16 and a standard deviation of 5
The standard deviation of the population parameter.
How the population parameter varies with repeated smples.
Whether the sample is from a normal population provided the sample is SRS
The possible values of the statistic and their frequencies from all possible samples.
.2729
.9918
.50
None of the above.
To estimate the level of confidence.
To specify a range for the measurements.
To give a range of plausible values for the population mean.
To determine if the population mean takes on a hypothesized value.
To determine the difference between the sample mean and population mean.