Mathematics and Research Methods

controls are important for comparing things

you can be your own control if tested before and after a treatment

using a ratio measurement or a baseline comparison helps control for differences in cell count, conditions, etc.

kills everything

you can autoclave a biohazard bag

mediating variable- explains the relationship between independent and dependent variable

confounding variable- influences both the independent and dependent variable

do an experiment with and without a certain variable to establish the strongest evidence for cause-effect

all other variables are kept the same

proactive treatment is better than reactive treatment

even better if its specific, targeted with no side effects

pick the answer that directly contradicts the data in the passage, no just that one that isn't supported

Ratio of the odds occurring in one group vs. the odds occuring in another group

mortality- deaths by disease during a time interval

morbidity- either incidence or prevalence

incidence- new cases of disease during a time interval

prevalence- how many total people have a disease

subjective bias- self-reported

social desirability bias- participants deal with sensitive/ethical subjects

selection bias- participants are usually self-selected

attrition bias- participants drop out of study over time

construct validity- whether a measurement actually measures the variable/construct being studied

criterion validity- whether a test correlates with other existing tests or measurements

external validity- generalizing results to other people and situations

internal validity- extent of causation proved

ecological validity- whether experiment replicates real-world conditions

Ability of a test to yield very similar results over repeated testings

A measure of the extent to which two factors vary together, and thus of how well either factor predicts the other

R = 0 means no relationship
R = 1 means perfect relationship
R = -1 means perfect inverse relationship

to calculate a variable, rearrange equation so all other variables are on the other side

always write units on your numbers, check the units in the question and the answers

for area and volume, conversion values are ^2 or ^3
1 m = 10^2 cm
1 m^3 = 10^6 cm^3

the process of turning an abstract variable into a measured or manipulated variable, even if cannot be quantified directly

need a control without the variable to prove causation

usually unethical in psychology and sociology experiments

eliminate influence of confounding variables, isolate the variable of interest

sampling biases
confounding variables

using subjects as their own control group by having half of them be experimental first and half of them be control first

controls for the order of tests presented
fatigue and boredom can affect test performance over time

supporting- discussing details and evidence to support a point

elaborating- explaining in more depth

participants must volunteer, can withdraw at any time

shocking people is ethical as long as you have consent

observing social interactions in real social settings

cross-sectional study- one point in time
cohort study- type of longitudinal study follows group over time

attempts to determine relationships between variables, but the researcher imposes no conditions as in an experiment

reduces influence of outliers when compared to the mean

pick sample that represents population you want to study

both internal and external validity are flaws - trade-off b/w them (more controlled = less generalizable)

is it generalizable

is it proving causation

independent variable needs to be measured before the dependent variable

are cheap and easy

study environmental influences of behavior

necessary- without it, no effect

sufficient- with it by itself, has effect

-/-
+/+ have both alleles (WT)

get a larger sample size

kg, kilogram

m, meter

sec, second

K, Kelvin

mol, mole

A, Ampere

Pa, Pascal

G, 1x10^9

M, 1x10^6

k, 1x10^3

d, 1x10^-1

c, 1x10^-2

m, 1x10^-3

μ, 1x10^-6

n, 1x10^-9

p, 1x10^-12

3600 seconds

1 cm^3 = 1 cc

1000 ml = 1 L

1000 L = 1 m^3

273 K

(K = C + 273)

1x10^-10 m

6.02x10^23 particles

4.18 J

C_H2O (specific heat) = 4.18 J/ g k

760 torr = 760 mmHg = 101.3 kPa

1 N/m^2 = 1 kg/m s^2

0.33 = 33%

0.2 = 20%

0.17 = 17%

0.14 = 14%

0.13 = 13%

0.11 = 11%

0.1 = 10%

0.09 = 9%

0.08 = 8%

0

0.5

0.7

0.9

1

0

1

0.9

0.7

0.5

0

-1

~1.7

~1.4

P = 2πr = πd

A = πr^2

A = 1/2 b (h)

A = 1/2 h (b_1 + b_2)

V = l x w x h

V = πr^2 h

V = 4/3 πr^3

x = move decimal to right depending on # of zeros (3.47 x 1000 = 3470)

/ = move decimal to left (470 / 100 = 4.7)

0.089 x 213

0.090 x 200

0.090 x 100 = 9

200 / 100 = 2

9 x 2 = 18

x = add exponents
(2x10^4)(4x10^2) = 8x10^6

/ = subtract exponents
(6x10^6) / (3x10^3) = 2x10^3

sqaure root x = x^1/2 if even number

(1x10^-6)^1/2
multiply exponents: (-6)1/2 =-3

= 1x10^-3

35/100 = ~ 1/3

since 33/100 = 1/3

7/33

33 = 1/3 out of 100

7/33 x 3/3 = 21/100 = 21%

-log(3.5x10^-5)

3.5/10 = 0.35

5 - 0.35 = ~ 4.65
(actual = 4.45)

-log(a x 10^-b)
b - (a/10) =


non neg. log:
-5 + 0.35 =
-b + (a/10) =