03.5 - statistics and data science

Question 1

data definition

Answer 1

facts, quantities, or items of information about a person or object

Question 2

data can be _ or _

Answer 2

quantitative (numerical) or qualitative (categorical)

Question 3

how do we collect data in the sciences?

Answer 3

by conducting experiments

Question 4

data helps us understand out

Answer 4

study system

Question 5

ways to get/use data

Answer 5

measure, observe, generate

Question 6

how to test hypothesis//expected outcomes of experiment

Answer 6

use statistics with collected data

Question 7

when do scientists use stats

Answer 7

To design studies and select sample sizes
To support or negate hypotheses
To understand error, uncertainty, and outliers in data
To interpret and summarize data
To make money??

Question 8

4 top skills of data science

Answer 8

data processing
statistics
data visualization
presentation

Question 9

summary statistics

Answer 9

presentation of data in an easy to understand and easy to digest snippets
better than using long lists of numbers - not informative or easily interpretable

Question 10

mean

Answer 10

average of data

Question 11

how to calculate mean

Answer 11

add variables together and divide by sample size

Question 12

median

Answer 12

middle number of data set

Question 13

how to find median

Answer 13

place numbers in order and find. middle value

Question 14

range

Answer 14

how spread out the data is

Question 15

how to find range

Answer 15

largest - smallest value

Question 16

best way to visualize data

Answer 16

use a box plot

Question 17

box plots show

Answer 17

minimum
first quartile
median
mean
third quartile
maximum
outliers

Question 18

first step after asking a research question

Answer 18

generate null and alternate hypothesis

Question 19

how to decide which hypothesis to reject

Answer 19

use more complex statistical analysis (like p-values)

Question 20

p value definition

Answer 20

the probability that any differences seen between datasets are due to natural variation

Question 21

p represents

Answer 21

probability

Question 22

p value will always be between

Answer 22

0-1 (0%-100%)

Question 23

higher p value means

Answer 23

differences in data are more likely to be due to natural variation

Question 24

which hypothesis is more likely with a higher p value

Answer 24

null

Question 25

which hypothesis is more likely with a lower p value

Answer 25

alternate

Question 26

lower p value means

Answer 26

differences in data are less likely to be due to natural variation

Question 27

p=0.68 means

Answer 27

there is a 68% chance that differences in the data are due to natural variation

Question 28

how sure must you be that statistical differences are due to random variation?

Answer 28

less than 5% chance

Question 29

when p>0.05

Answer 29

there is more than a 5% chance that differences between dataset are due to random chance insignificant amount of difference accept null hypothesis

Question 30

when p<0.05

Answer 30

there is less than a 5% chance that differences between dataset are due to random chance significant amount of difference accept alternate hypothesis

Question 31

F test statistic

Answer 31

X^2 statistic tells the amount of difference between groups

Question 32

higher value of F test statistic means

Answer 32

more variation within the data

Question 33

degrees of freedom tells

Answer 33

how many individual points or groups are within the data

Question 34

higher degrees of freedom =

Answer 34

more significant results

Question 35

degrees of freedom between groups =

Answer 35

number of groups -1

Question 36

degrees of freedom within groups

Answer 36

number of samples - number of groups

Question 37

post-hoc tests are used when

Answer 37

there are differences (p<0.05) to see where the differences are

Question 38

tukey's HSD compares

Answer 38

each treatment pairwise to tell us where differences are

Question 39

interpretation of results in tukey's hsd

Answer 39

If p < 0.05 then there is a difference between the two groups If p > 0.05 then there is no difference between the two groups