scientific method

Question 1

environmental science

Answer 1

how earths environmental systems function in respect to the cycling of matter/energy

Question 2

scientific method

Answer 2

orderly approach for gathering/accumulating knowledge that is used to learn how natural systems work

Question 3

steps of scientific method

Answer 3

1) observation of something that cannot be immediately explained
2) research question
3) qualitative hypothesis
4) experimentation
5) statistical hypothesis
6) data collection and analysis (null hypothesis)

Question 4

scientific hypothesis

Answer 4

must make predictions that are specific and can be supported/refuted through experimentation or additional observation

Question 5

experiment

Answer 5

systematic approach to testing validity of a hypothesis

Question 6

why is there no such thing as “proof”

Answer 6

always opportunity for an alternative explanation

Question 7

scientific theory

Answer 7

integrated explanation for a set of related observations or events that is based on a series of hypotheses that have been verified multiple times by different groups

model developed from a commonly accepted scientific principle that describes the way a system works

continually evolving

Question 8

theories explain …. not just …..

Answer 8

how, why

Question 9

scientific law

Answer 9

always observed to be true. absolute scientific fact

Question 10

strong interference approach

Answer 10

emphasizes formulation of multiple competing hypotheses prior to experimentation

Question 11

statistical hypothesis

Answer 11

constructed using variables

can be null or alternative

tied to the experiment

Question 12

variables

Answer 12

conditions with a logical set of either categorical or continuous attributes that are measured, manipulated, or controlled

Question 13

categorical variable

Answer 13

attributes that can be grouped into discrete categories

Question 14

continuous variable

Answer 14

variable that can take on any value

Question 15

independent variable (explanatory)

Answer 15

goes on the x axis

explains and effects changes

Question 16

dependent variable (response)

Answer 16

goes on y axis
response to independent variable

Question 17

alternative hypothesis

Answer 17

expressed in terms of what pattern the scientist expects to detect from the experiment

Question 18

null hypothesis

Answer 18

pattern that would occur if the null hypothesis were not true

“no change in”

tested during experimentation

Question 19

you can reject a null hypothesis when

Answer 19

you have proved the alternative hypothesis is true

Question 20

mensurative study

Answer 20

observational

experimenter does not manipulate the system

data collected in its natural state

Question 21

manipulative study

Answer 21

study in which the researcher manipulates one or more variables of interest called treatments

Question 22

treatment groups/levels

Answer 22

unique attributes associated with categorical variable

Question 23

control

Answer 23

experiment treatment that experiences the same environmental treatment as all of the other treatments, but is not exposed to the manipulated variable

Question 24

experimental unit

Answer 24

replicate

individual physical entities that are observed or manipulated

Question 25

sample size

Answer 25

number of replicates

n

Question 26

3 principles of experimental design

Answer 26

1) treatments should be replicates
2) experimental units should be individual entities
3) treatments should be randomly applied to experimental units

Question 27

ANOVA

Answer 27

t test/variance

use with categorical (discrete) treatment levels

Question 28

use regressions with

(scatter/line plot)

Answer 28

experiments that have continuous variables

Question 29

p value

Answer 29

metric that ranges from 0-1 and describes probability of rejecting a null hypothesis when it is actually true (type 1 error)

Question 30

what p value is significant

Answer 30

less than 0.05

means that you can reject the null hypothesis

Question 31

hypothesis vs theory

Answer 31

hypothesis explains why, theory explains how

theories are a mechanistic model of how something occurs

ex) theory: natural selection. explains how we got here

Question 32

alternative hypothesis is a type of

Answer 32

statistical hypothesis

Question 33

quantitative hypothesis

Answer 33

must have numbers in the dependent variable

more descriptive than statistical

Question 34

bar graphs hide experimental units in favor of

Answer 34

an average

Question 35

a statistically significant number means

Answer 35

there is a relationship other than the null hypothesis

Question 36

what do you need to be able to accept the alternative hypothesis

Answer 36

1) plotted data that matches the relationship in the alternative hypothesis
2) a significant p-value