100% tevredenheidsgarantie Direct beschikbaar na je betaling Lees online óf als PDF Geen vaste maandelijkse kosten
logo-home
Eerder door jou gezocht
Eerder door jou gezocht
logo
Management Research Methods 1: class notes €6,49
In winkelwagen
Snel navigeren naar
Voorbeeld
  2.  
  3. Universiteit Van Amsterdam (UvA)
  4.  
  5. Management Research Methods 1

College aantekeningen

Management Research Methods 1: class notes
 0 keer verkocht

This course reviews and explains the basic statistical concepts and techniques that are used in the area of Management and Business Administration and MSc theses, and emphasizes the practical application of the various techniques using SPSS software.

Voorbeeld 3 van de 24  pagina's

Document informatie

  • 4 juni 2019
  • 24
  • 2018/2019
  • College aantekeningen
  • Onbekend
  • Alle colleges

Onderwerpen

Geschreven voor

Alle documenten voor dit vak (4)

Verkoper

avatar-seller
fiona54

Ontvangen beoordelingen

Voorbeeld van de inhoud

MRM I NOTES


WEEK 1: DATA

What is “data”?
- Various properties (variables) measured from a set of things, people (units)
- Data has a fixed structure
o Each column = properties of the unit
o Each row = unit, the thing we’re studying

What is a “case” or “unit”?
- Experimental or observational entity being measured (students, cats etc.)
- Each case or unit has variables

Types of measurement
- Categorical measurements shown with distinct categories
o Binary variable
 Two categories (dead/alive, black/white).
 Offers the least amount of information
 Need minimum 300 units for good sample:
 The less information shown, the larger the sample needs to be
o Nominal variable
 Has several categories (omnivore, vegetarian or vegan)
o Ordinal variable
 Assesses value on a scale (bad, ok, good, great)

- Numerical measurements: shown with numbers
o Discrete data:
 Round number counts (nr of defects, delayed flights)
 Cannot be negative, must be count-able
o Continuous data:
 A numerical value (body temp, height, weight)
 Offers the most amount of information
 Need minimum 30 units for good sample

Information amounts:
- We can always downshift information amounts (from discrete to nominal, subtracting
amount of information)
- We cannot shift upwards: we cannot add information
- Downshifting information is non-reversible.
o Body length less than 160 cm we convert to category “small”
o Body length between 160 cm – 180 we convert to category “med”
o Body length greater than 180 cm we convert to category “tall”

The lower the amount of information, the larger the sample needs to be


Complementary research methods:
- Research involving numbers = quantitative methods
- Research analyzing language = qualitative methods

Research:
- Start with question you want to answer, based on observation, anecdotal, etc.
- Generate theory, generate hypothesis
- Identify variables
- Gather data, measure variables
- Analyze data, fit model to graph
- Theory is supported or not

,Falsification: proving a theory wrong

Variables: things that change based on circumstances
- Independent variable: the “causing” variable (predictor), shown as “x”
- Dependent variable: the “effect” variable (outcome)
- Categorical variable: things that belong to various categories
- Binary variables: things that fall into two categories
- Nominal variable: a variable with the same name but with more than two categories
(cat/brown, cat/black, cat/white, cat/orange); can use numbers
- Ordinal variable: categorical variables on a value scale (awful, bad, ok, good, great)
- Continuous variable: gives a score for each thing being measured, can take on any
value (negative, decimal, etc.)
- Interval variable: when points on a scale are equidistant to each other
- Ration variable: ratio of values along the scale have meaning: true “zero”, and that
“4” is twice as meaningful as “2”
- Discrete variable: round numbers only, no negative numbers

Parameters:
- Different from variables
- Constants believed to be fundamental truths
- The mean and median represent the center of the distribution

Level of measurement:
- That which is being measured and the numbers that represent what is being
measured

Validity: whether an instrument is measuring what it is supposed to measure
- Criterion validity: how well one measure predicts an outcome for another measure
(a high GRE score predicts how well someone does in school)
- Concurrent validity: data recorded simultaneously with new instrument against
existing criteria
- Predictive validity: data from a new instrument are used to predict observations at a
later point in time
- Content validity: the degree to which individual items represent the construct being
measured
- Test-retest validity: test the same group twice – a reliable instrument produces
similar results at various points in time

Reliability:
- Whether an instrument measures consistently across different situations

Correlational research:
- We observe what naturally goes on without directly interfering with it
- Cross-sectional research

Experimental research: we manipulate one variable to see its effect on another


Assessing data

Is the sample representative?
- Does the sample represent the total population?
- Can the sample findings be generalized to an entire population?
- Eg: only sampling students in Amsterdam for a country-wide study

Is the data valid?
- Does data reflect what it should reflect?
- Can it be used to answer the research question?
- “Face validity check”: checking data for obvious errors and mistakes

, - Were there other problems / irregularities during measurement?

Is there a measurement error?
- Discrepancy between the actual (real life) value we are trying to measure and the
number we use to represent that value
- Example: you (in reality) weigh 80 kg. According to your bathroom scale, you weigh
83 kg. The measurement error is 3 kg.
- Two types of measurement error:
o Systematic: problem with the system; the results are accurate but “off”:
measuring tool isn’t calibrated
o Random: problems unrelated to the system, results are all over the place;
measuring tool is non-functional, imprecise

Operational definition:
- Describe measuring procedure



Describing data: location

Median:
- The “middle score” when data is ordered
- In a lineup of 11 datapoints, nr 6 is the median
- For an even number of results, use the mean of the two central numbers
Mean:
- The sum of the data (sigma) divided by the number of datapoints (n)
- Symbolized by “x bar”




If the median is lower than the mean…
- You have major outliers in the high end of the distribution
- Eg. one Bill Gates among normal to measure personal net worth
- Graph is positively skewed

If the median is higher than mean …
- You have major outliers in the low end of the distribution
- Eg. one guy with gambling debt among normal to measure personal net worth
- Graph is negatively skewed.


Describing data: distribution

Range:
- The smallest value subtracted from the largest
- Highest value = 100, smallest = 20? Range = 80
- Very sensitive to outliers

Interquartile range:
- The middle 50% of the data
- Range between upper and lower quartiles
- Upper quartile: the median of the upper half of the data
- Lower quartile: the median of the lower half of the data

Dit zijn jouw voordelen als je samenvattingen koopt bij Stuvia:

Bewezen kwaliteit door reviews

Bewezen kwaliteit door reviews

Studenten hebben al meer dan 850.000 samenvattingen beoordeeld. Zo weet jij zeker dat je de beste keuze maakt!

In een paar klikken geregeld

In een paar klikken geregeld

Geen gedoe — betaal gewoon eenmalig met iDeal, creditcard of je Stuvia-tegoed en je bent klaar. Geen abonnement nodig.

Direct to-the-point

Direct to-the-point

Studenten maken samenvattingen voor studenten. Dat betekent: actuele inhoud waar jij écht wat aan hebt. Geen overbodige details!

Veelgestelde vragen

Wat krijg ik als ik dit document koop?

Je krijgt een PDF, die direct beschikbaar is na je aankoop. Het gekochte document is altijd, overal en oneindig toegankelijk via je profiel.

Tevredenheidsgarantie: hoe werkt dat?

Onze tevredenheidsgarantie zorgt ervoor dat je altijd een studiedocument vindt dat goed bij je past. Je vult een formulier in en onze klantenservice regelt de rest.

Van wie koop ik deze samenvatting?

Stuvia is een marktplaats, je koop dit document dus niet van ons, maar van verkoper fiona54. Stuvia faciliteert de betaling aan de verkoper.

Zit ik meteen vast aan een abonnement?

Nee, je koopt alleen deze samenvatting voor €6,49. Je zit daarna nergens aan vast.

Is Stuvia te vertrouwen?

4,6 sterren op Google & Trustpilot (+1000 reviews)

Afgelopen 30 dagen zijn er 69411 samenvattingen verkocht

Opgericht in 2010, al 15 jaar dé plek om samenvattingen te kopen

Begin nu gratis
€6,49
  • (0)
In winkelwagen
Toegevoegd