Week 1 Lecture, why do we need stupid stats?

Question 1

Why do we need statistics ?(3 )

Answer 1

to answer interesting questions, generate new knowledge and tells us odds of being wrong

Question 2

What are the two types of data analysis and what do they test?(the two Q’s)

Answer 2

1) Quantitaive: testing theory’s using numbers
2) Qualitative: testing theory’s using language

Question 3

What are the 5 steps to the research process? (IGGCA)

Answer 3

Initial observation
Generate a theory
Generate hypothesis
Collect data to test theory
Analyze data

Question 4

What’s the difference between a theory and a hypothesis? geuss and ..

Answer 4

Hypothesis is a testable idea usually based on a theory (an assumption)

Theory is a principal or set of principals that explain known findings on a topic

Question 5

What are the two ways you can conduct research and how? Finding something or someone finding..

Answer 5

Initial observation- find something needing explaining

Follow research stream: research developed over time by many researchers

Question 6

What is a variable and it’s two types and what do they measure ?

Answer 6

anything that can be measured and can differ across entity’s in time

1) Independant Variable- what causes change
2) dependant Variable- what detects change (whats measured)

Question 7

What’s a construct and two examples(something we can’t see) and what type of construct do we use instead?

Answer 7

Variable we are measuring indirectly. Variable cannot be measured or observed thus needs other measures to validify like a psychological construct that can be measured and defined.
Example: Anxiety,Depression

Question 8

What is a research stream and how do you find it from an old study? literally like a stream

Answer 8

Stream of research is guided by a topic and like a stream bumps and ricks are in the way uncovering new questions. look backwards or forwards to see who identified it.

Question 9

What does it mean by operational?

Answer 9

any type of variable that is able to be measured or manipulated

Question 10

What’s falsification?

Answer 10

Disproving a theory/hypothesis

Question 11

How do you write out The null hypothesis, what do the variables represent and what are the two names for research hypothesis?

Answer 11

NULL: H0: u1=u2
H-Null U1- Mean of population U2- effected

Non directional
Directional

Question 12

What is a non directional research hypothesis and write it out

Answer 12

H1:x1 (bar)≠x2(bar)

Has no effect on variables

Question 13

What is a directional hypothesis and write it out?

Answer 13

H1: x1(bar) > x2(bar)

Has an impact on one of the variables

Question 14

Which of the two research hypothesis holds more power and why?

Answer 14

Directional hypothesis holds more power if you know the direction of change as the critical value shifts (value changes as one variable is being effected)

Question 15

What are the 3 Names each for IV’s (PPM) and Dv’s (POM)

Answer 15

IV- Proposed cause, predictor variable, manipulated variable

DV- Proposed effect, outcome variable, measured not manipulated variable

Question 16

Levels of measurement: NOIR + B What are they and one example for each

Answer 16

Nominal- no group is better than another: hair colour, gender
Ordinal- Set up by groups of hierarchy: Rate my professer (likerd scales), speed of cars
Interval-no set 0 point: Longitude and latitude, temperature
Ratio-has set 0 point: crime rate, age
Binary- In one group or another never both: morse code, dead or alive

Question 17

What’s measurement error? and an example

Answer 17

Discrepancy between the actual value we are trying to measure and the number we receive as a result.

You weigh 100 lbs the scale says 103, 3 lbs is the measurement error

Question 18

What are the 3 basic research designs? (CCE)

Answer 18

Correlational research
Cross sectional research
Experimental research

Question 19

What is correlational and cross sectional research? (real world and different representerz)

Answer 19

Correlational- observing relationship between 2 variable without interfering
Cross sectional: data comes from different age groups and different people representing each

Question 20

What is experimental research? (like partial correlation, what do we leave out 1,2…)

Answer 20

One or more variables systematically manipulated to see outcome on an outcome variable by itself or in combination

Question 21

What’s the three criteria in Cause and effect (Hume,1748) Goes in circle almost

Answer 21

1) cause and effect must occur close in time together
2) cause must occur before the effect
3) no effect without presence of cause

Question 22

What is another name for a confounding variable and what is it?

Answer 22

Tertium Quid

Variable we may not now or have measured, but still potentially has effect on outcome variable (DV)

Question 23

( Methods of data collection) What are the 5 names for Independent variable (IBBUU) and Dependent variable (DRWPC)

Answer 23

Independent measure
between subjects design
between group
unpaired
uncorrelative

Dependent measure
repeated measures
within subject
paired
correlative

Question 24

What are the three types of variation and what do they account for(1 example each)? (created by, created by, minimize)

Answer 24

1. Systematic variation- differences in performance created by specific identifiable source (bias)
2. Unsystematic variation- differences in performance created by unknown factors (age)
3. Randomization- minimizes unsystematic variation

Question 25

What is random selection? (defined) and random assignment? (groups) What is the difference between two?

Answer 25

Random selection: Choosing participant from defined population so you can state probability of individual being included

Random assignment : putting people in groups based off laws of random chance
-controls for variance we don’t know exists

Question 26

What are Frequency distributions and what’s another name for them?

Answer 26

Histograms, Graph plotting values of observations on X axis with a bar showing how many times each value occurred in data set

Question 27

What are the 2 property’s of Frequency distributions and explain what two kinds of things go into each property? (positive,negative tails and values) (who’s the short little blonde kid who worked at BB?) (platypus)

Answer 27

1) skew: symmetry of distribution

Positive skew: scores bunched at low values with tail pointing at high values

Negative skew: Scores bunched at high values with tails pointing to low values

2) Kurtosis -heaviness of tails
Platykurtic- Light tails (can be too flat)
Leptokurtic-heavy tails (can be too pointy)

Question 28

Why is random sampling so hard? And why does the mean, mean nothing?

Answer 28

Hard to define a population for random sampling.

Mean has no measure of spread so the values can be all over the place (sprawled) or unseen and you wouldn’t even know

Question 29

Why do we call stats rules assumptions and what happens if you break them?

Answer 29

Called assumptions as they are broken often and can cause a type 1 error (stating something untrue in experiment) When you do break an assumption do some research to see what to do next

Question 30

What are the 3 measures of central tendency and how many of … does each contain? (MBM)

Answer 30

Mode-most frequent score 1 mode
Bi modal-2 modes
Multi Modal-7 modes

Question 31

What is the normalicy assumption?

Answer 31

That most of our stats are based on a normal curve (bell curve), when we don’t use normal bell curve we violate normalicy.

Question 32

How do you find the median mean and range?(middle, sum of scores, subtract)

Answer 32

Median- find middle number with data set lined up smallest to largest
Mean- find sim of scores and divide by numbers in data set
Range- subtract smallest score from the biggest

Question 33

What’s the dispersion in Interquartile range and what of the median do they represent ? (3 quartiles)

Answer 33

1) second quartile- median
2) lower quartile -median of bottom half of data
3) upper quartile - median of upper half of data

Question 34

What does variability measure?

Answer 34

Tells us how well the measure of central tendency portrays entire data set

Question 35

What are two types of deviance and what does deviance do?

Answer 35

Deviance and total deviance

Calculates spread of scores by looking at how different each score is from the mean

Question 36

What does IQR represent along with range?

Answer 36

IQR is range of values in middle of the score set and asses variability where most (middle) scores lie

Range: is dispersety of scores in data set, shows highest and lowest number scores go to

Question 37

What does SEM and SD represent?

Answer 37

Sem- shows how well standard deviation could model real world

SD- show how dispersed data is in relation to the mean

Question 38

What do COI represent?

Answer 38

Represent the range that will theoretically capture the true mean 95/100

REPRESENTED BY ERROR BARS