FW370 Exam Study Set

This is the study set for CSU's FW370 from Spring 2025 taught by Dr. Lise Aubry

Manipulative experiment

direct alteration of the predictor variables in a lab or field setting, can answer causative questions

Natural experiment

measurements or observations of biological systems in the absence of manipulations by the investigator, often answer descriptive questions

two-tailed t-test

What kind of model do you use to show the investigator if there is a difference between two population means, but not the direction of the difference?

One-tailed t-test

a statistical test that compares whether the mean of one population is more, or less, than that of the other population it is being compared to

inductive reasoning

This type of reasoning moves from Specific to general is its line of thought and draws conclusions from large bodies of observations BUT does not test hypotheses

deductive reasoning

This is the type of reasoning where you start with a general idea and work down to the more specific (less commonly utilized today)

Hypotherico-deductive

This type of reasoning gains support for a hypothesis by testing the predictions and by utilizing falsification and repeatability

Plausibility Generality Specificity Testability Feasibility

What are the five features of a good hypothesis

hypothesis predictions testing Strong support theory

What are the steps of the scientific methods simply put

methodical repeatable verifiable

What are the three main components of scientific research

Null hypothesis

What is the hypothesis of no change that is often abbreviated as H₀

Alternate hypothesis

What is the hypothesis that must be mutually exclusive and is abbreviated as H_a

the observed difference was so great it is unlikely to have been caused by chance alone

What does it mean when we reject an null hypothesis?

prediction

a statement about what you expect to find from your experiment

probability of commiting a type one error called alpha

Define level of signifigance

area under the standard deviation curve inside t critical representing probability of the sample statistic occurring if the null hypothesis is true

Define P-value

each sampling unit in the population has an equal chance of being selected

Define simple random sampling

divides the population into groups called strata and a sample is taken from each using other types of sampling

define stratified sampling

a spatial grid is used to generate equally sized sampling regions and sampled within each grid cell either randomly or aligned to the cells center

define systematic sampling

Primary sampling areas are located at random within an overall study area first then sampling units are located at random within each primary sampling area

define cluster sampling

observations within a single unit or treatment not independent of one another

What are pseudo replicates?

an aggregate of subjects which we wish to describe adn draw conclusions about

Define population

a collection of subjects selected within the study population representative of the target population

define sample

measurement unit

define sample unit/observation

qualitative or quantitative measured or recorded for each subject in the sample

define variable

a set of values for all variables of interest measured across all individuals in the study

define dataset

Variables can only be integers

define discrete data

any real number

define continuous data

unordered categories like eye color

define and give an example of nominal data

order categories like behavior

define ordinal data and give an example

mean median mode

What are measures of center

standard deviation, varience, quartiles

what are measures of dispersion

an estimate of a population parameter derived from a sample

define statistic

the difference between the sample and the population tha tis due solely to the incomplete enumeration of all elements of the population

define sampling error

tendency to favor the selection of units having particular characteristics

define sampling bias

how close is the measured value to the true value

define accuracy

how close are repeated measures to each other

define precision

accuracy precise

Sampling bias induces a lack of ______ even when the data is ____

precision

Sampling error induces a lack of _____ and decreases as sample size increases

resutls when most convinient units are chosen from a population

Define Convenience sample

obtained at the discretion of someone who is familiar with the relevant characteristics of a population

define judgement sample

all units within the population have a known or estimable probability of being choses

defien probability or random sample

straight-line segments laid out in the area to be sampled

What are transects?

measurements are taken from a set of points established throughout a target population

define points (point counts)

small geographic areas used to sample habitat characteristics or count animals

define plots( quadrats) sampling units

unbiased estimate of parameters, independence of samples, precise estimates of parameters, reliable inference of treatment effects

what are the 4 main important reasons for proper sampling

The result of a random experiment

Define probability outcome

the set of possible outcomes

define probability sample space

the long-run relative frequency of occurence of each possible event

define probability

the occurrence of a phenomenon of interest

define event in terms of probability

the number of events

Define Trial in terms of probability

P(A and B)= P(A)*P(B*A)

what is the equation for a dependent shared probability event between A and B

P(A and B)= P(A) *P(B)

what is the probability equation for an independent shared event

an event in relation to another event is the probability that the event happens given the other event has already happened

what is conditional probability

a discrete frequency distribution which gives the probability of a number of independent events occurring in a fixed time

what is a Poisson distribution

Bell-shaped and symmetrical asymptoting at the x axis described by mean and standard deviation

What is a normal distribution?

68

In a normal distribution one standard deviation from the mean in both directions yields what percentage of the distribution

describe patterns in population like means and standard deviations

What are descriptive statistics

Make inference about populations like t-tests ANOVA and regerssions

What are inferential statistics

the unpaired compares two pop means and the paired compares means from same sample two times

What is the difference between a two sample paired t-test and a two-sample unpaired t-test

bird abundance before and after a burn

what is an example of a two sample paired t test

the variation between populations

what does treatment effect refer to?

the natural variation within a population

what does error refer to in statistical testing

the difference is larger that what we would expect due to chance alone

How do you phrase an alternative hypothesis your believe to be greater than the null

what we are measuring

what is the response in ANOVA

the interaction of factors

If One-way ANOVA is an extension of the t-test to 3 or more samples than what is the two-way ANOVA

the value of one observation does not influence or affect the value or other observations

what is the independence of observation assumption of ANOVA

ANOVA tests

what is this a graph of

sums of squared normal random variables

What is Chi square random variables?

the ratio of two independent chi square random variables divided by their repective degrees of freedom

What is an F random variable

when the variation between groups is large compared to variation within groups

In terms of f test what tells us that the treatment effect is stong?

when the f statistic is less than the f critical

when is there no treatment effect in terms of the F test?

The minimum calculated amount of difference between groups for there to be an honest difference between groups

What is Honest significant difference

a variable of interest

What is a factor in terms of a two way anova

a particular value or state of a factor

what is a level in terms of a two way anova

ANOVAs with two or more outcome (dependent) variables, correlated, and in the same analysis

what is a MANOVA

any of the ANOVAs and also trying to control for an external influence to the dependetn variable

what is a ANCOVA

the analysis of covarience used to compare two or more regression lines

What is another definition for ANCOVA