Summaries
Find the mode and range of this set:
{4, 7, 7, 7, 9, 9, 10, 11, 12}
Mode: 7
Range: 8
What percent of data in a standard normal curve falls within two standard deviations of the mean?
95%
What is the difference between an open-ended and a closed-ended question?
Open-ended: respondents create their own answer
Closed-ended: only certain answers are given as choices
What code is needed to create a graph of the gender variable in the cdc data set?
bargraph(~gender, data = cdc)
What was the treatment given to the experimental group in the Mythbusters episode we watched this year?
Yelling at/talking nicely to/playing music for plants
Find the median of this set:
{4, 7, 7, 7, 9, 9, 10, 11, 12}
9
How many standard deviations above or below the mean is a 65" tall person, if the mean of normally distributed heights is 66" with a standard deviation of 2"?
0.5 below
What is a feasibility constraint?
A reason one could not perform an experiment; cannot assign grouping
What does "set.seed()" do in R?
It takes the randomness out of a random process, making it replicable.
If 40% of marbles are red, how many red marbles are there in a bag of 500?
200
Find the mean of this set:
{4, 7, 7, 7, 9, 9, 10, 11, 12}
76/9 or 8.4444444444...
A machine puts bolts in a box. The mean number of bolts in any box is 110 with a standard deviation of 2 bolts. 16% of boxes have more than _____ bolts.
112
What does it mean if you are in the 35th percentile for height?
You are as tall or taller than 35 people in a group of 100.
What does "filter()" do in R?
It creates a new dataset by pulling observations from an existing set according to the filter criteria
Name at least 4 of the 5 classwide campaigns that we did this year.
food habits
personality color
stress and chill
time perception
time use
Find the IQR of this set:
{4, 7, 7, 7, 9, 9, 10, 11, 12}
3.5
A group of normally distributed test averages has a standard deviation of 5. If Ana's test average of 76 has a z-score of 1.2, what is the mean?
70
What does it mean if the correlation coefficient between two variables is close to -1?
There is a very strong negative linear relationship between the variables.
What does "sample()" do in R?
It lets us take a random sample of values of a variable.
How many labs did we do this year?
18 (1A-H, 2A-F, 3A-D)
Find the standard deviation of this set. (Answers within 10% of actual value are accepted.)
{4, 7, 7, 7, 9, 9, 10, 11, 12}
2.455. (range of accepted answers: 2.2095 - 2.7005)
In a standard normal distribution with mean of 60 and standard deviation of 6, what percent of the data falls between 54 and 72?
81.5%
What is the difference between causation and association?
Causation: cause and effect
Association: two things are statistically linked, but one does not cause the other
What does "mutate()" do in R?
It mutates a data set, perhaps by creating a new variable/column.
Say the following without any mistakes: Peter Piper picked a peck of pickled peppers. If Peter Piper picked a peck of pickled peppers, how many pickled peppers did Peter Piper pick?
What word describes repeated consonant sounds at the beginning of words?
Alliteration