Unit 1
If a stemplot's key reads 7 l 0 represents 70 years, then what does 8 l 3 represent?
83 years
Is a strong positive correlation coefficient closer to 1 or 0?
1
By allowing participants to choose which group of the study they are in, you create a _____ variable in your study, making your results void.
confounding
What is the probability of rolling a 2 or 3 on a six-sided dice, assuming that each side has an equal chance of being rolled.
2/6, 1/3, .333
Is a smaller sample size likely to have a greater or smaller variability?
greater
How do you determine the IQR from a boxplot?
You look at the length of the box
Does this describe a positive or negative correlation?
As one variable increases, the other decreases.
negative
You observe that there is a strong correlation between hours of sleep and test scores through an observational study. Can you determine that sleeping more causes better test scores?
no.
How would you read P(A U B) out loud?
Probability of A or B
How do you calculate Standard Deviation of a sampling distribution for proportions?
sqrt[(p(1-p)/n]
What percent of the data is within the IQR?
50%
What measures the strength and direction of a linear relationship between two variables?
Correlation Coefficient
Assigning every individual in a population a random number, then choosing x numbers without replacement to sample is an example of ___
Simple Random Sampling (SRS)
How do you determine independence?
A sampling distribution can be assumed normal when _____
The sample is taken randomly
If a distribution is skewed left, then is the mean or median greater?
mean
The slope of a least squares regression line will ____ when a lower outlier is removed.
decrease
You decide you want to survey a school. You decide that instead of surveying the entire school, you will divide the population into what homeroom they are in. Then, you will survey three random students from each homeroom. This is an example of _____
stratified random sample
What is the probability of not rolling a prime number on a six-sided fair dice?
2/6, 1/3, .333
30
When is a histogram appropriate over a dotplot?
When the data set is large
If the correlation coefficient of a set of data is .7, then the proportion of the variation is __
.49
There is a correlation between ice cream sales and drowning. What is a possible confounding variable for this observation?
Its hot out so more people will want to swin and more people will want to eat icecream
What is the probability that on two fair six-sided dice, you roll a 2, then roll an even number?
.0833, 3/36
Which value of p will create the greatest Standard Deviation?
1/2