Chapter 1
What is quantitative?
The term for a distribution which is unskewed, with more observations tending towards the center of the scale, exponentially decreasing on either end.
What is a normal distribution?
What is regression?
The sampling method where every set of n individuals has an equal change of being the actual sample selected.
What is simple random sampling?
The 3 major measures of center.
What is mean, median, and mode?
A distribution has many more observations on the lower end of the scale than on the upper end. The skew is this
The primary measure of spread of a distribution.
What is standard deviation?
What is the sum of squares?
The rule determining what percentage of each observation lies within 1, 2, or 3 standard deviations of the mean on a normal distribution.
What is the 68, 95, 99.7 rule?
A relative frequency pie chart differs from a relative frequency bar graph in more than just shape. The connotation behind a pie chart is this.
In 1995, the SAT scores were normally distributed. The mean was 470, and the standard deviation was 110. A scholars who scored 500 on this scale would have this z-score.
What is 0.2727?
A school counselor chooses 25 scholars from a population of 1,500, and observes the number of extracurricular activities that scholars do and their GPA. The correlation is found to be very high. The scope of inference is this:
What is neither causal nor generalized out to the population in general?
What is trolling?
This is sometimes called the correlation coefficient, but its values are between 0 and 1, as opposed to between -1 and 1.
What is "r^2"?
The mean salary of all female workers is 35000. The mean salary of all male workers is 41000. This statement can be said about the mean salary of all workers.
What is between 35000 and 41000?
99.7% of American men have heights between 5'0" and 7'0" (fictitiously). The estimated standard deviation is this.
What is 4"?
The values of the Correlation Coefficient "r" are in this range. A number close to zero means there is no correlation.
What is between -1 and 1?
Ice Cream sales and Shark attacks are highly correlated. This is an example of when two response variables are both affected by a single explanatory variable, which can also be called this:
What is a lurking explanatory variable?
In order to determine that the observed phenomena generalized out from our sample to the population of interest, this must be used.
What is random sampling from the population of interest?
You record age, marital status, and earned income of a sample of 1463 women. The number and type of variable you have recorded is this.
What is 2 quantitative and 1 categorical?
Suppose that 1000 University applicants took an entrance exam, and Pete received a score of 68, which and 730 people scored less than him. Another measure of the people who scored below him is this.
What is percentile?
There is found to be a linear relationship with strong correlation between the number of chirps per minute of a cricket, and the ambient temperature, with y equals 25.2 plus 3.3 x, where y is the temperature, and x is the number of chirps. The predicted temperature increase for an increase in chirps is this.
What increases by 16.5 degrees?
In order to determine causality as opposed to simple correlation in a statistical study, this must be introduced.
What is a random allocation between treatments of the observations?
The owner of a chain of supermarkets notices that there is a positive correlation between the sales of root beer and the sales of ice cream. While causal relationships cannot be verifiably established in observational studies, 5 different points should be considered. Name 2.
1 - How strong is the association? 2 - Is the association consistent? 3 - Does the explanatory variable precede the response variable? 4 - Do larger explanatory variables coincide with a larger effect? 5 - Is the alleged cause scientifically plausible?