Samenvatting

BBS1003-Statistics-Syllabus summary, lectures, videos, Andy Field

3 keer verkocht

Instelling
Maastricht University (UM)

This summary scored me a 9.7 on the final exam! This document contains a summary of the statistics syllabus, notes from the lectures, notes on the video lectures and a summary of parts of Andy Field's statistics book.

[Meer zien]

Voorbeeld 4 van de 43 pagina's

Bekijk voorbeeld

Heel boek samengevat? Onbekend
Geupload op 5 februari 2019
Aantal pagina's 43
Geschreven in 2018/2019
Type Samenvatting

statistics

Volgen

Jody2711 Lid sinds 6 jaar 20 documenten verkocht

€5,99

In winkelwagen

Op verlanglijstje

100% tevredenheidsgarantie
Direct beschikbaar na je betaling
Lees online óf als PDF
Geen vaste maandelijkse kosten

Summary statsttis syllabus

Chapter 1
Variables
Various types:
 Qualitative  nominal and ordinal
o Also called categorical or discrete
 Quantitative  interval and ratio
o Also called continuous  variable can take any number

Frequentiy table
 To summarize e.g. scores of students
 Vertically  columns
 Horizontally  rows

Bar tihart
 Graph with frequency/count on vertical aais and scores on horizontal aais
 Blank between each bar  the bar can be assigned to e.g. any political party, so
there is a blank between each pair of bars and the distance between the bars has no
meaning
 Often used to summarize outcome of qualitatve variable

Histogram
 For summarizing quantitative variables
 No space between bars  scores are connecting as it should for interval and ratio
variables
o Each bar has surface eaactly equal to frequency of score represented by that
bar
 To ensure this for a bar width other than 1, the numbers on the y-aais
have to be divided by the class width
o Horizontal end points of each bar are chosen by user  determine width
 For very large sample sized, percentages can be presented instead of frequencies
Boundaries
 [..,..)
o [ = included in class interval
o ) = not included in class interval

Theoretti distributon
 When number of classes becomes very large 
obtain theoretic distribution

,Measures of tientral tendentiy
 Mode
o Score with highest
frequency
 Median
o Middle value
 Mean
o Average
Skewness
 Right skewed (+) 
average is the highest
because most sensitive to
eatreme values  right skew means there are more large values

Variantie
 How much subjects difer from each other with regard to their scores
 You can calculate how much measurements difer from the mean  but then -2 and
+2 would cancel each other out  you can solve this by calculating the average sum
of the quadratic diference of all values around the average  variantie

 8 = number of measurements

 If you do not divide by N (8 in this case)  statistic is called variation
o So variation = N a var(Xn)
 Population vs sample:
o Population  divide by N-1
o Sample  divide by N

Standard deviaton
 Square root of variance
 More usable  eapressed in same scale as value (so e.g. inches)
o Variance is not  square of value, so e.g. square of inches

Normal distributon
 Theoretic distribution
 Features:
o Symmetric  so average, mode and median will coincide

, o 68% of scores falls within 1 standard deviation
of average
 95% will fall within 2 standard deviations
 99.7% will fall within 3 standard deviations

Pearson tiorrelaton
Standardization
 Covariance needs to be converted to standard set of units to avoid dependency on
measurement scale  standardizaton
o Standard deviation typically used as unit
 By dividing the distance from the mean by the standard deviation, you
get the distance in standard deviations
 Standardized covariance is known as tiorrelaton tioeftiientt

o Sa is standard deviation of frst variable, Sy is of second variable
o Coefficient is known as Pearson product-moment correlation coefficient
o Can only be between -1 and +1
 -1 = perfectly negative correlation  values go in same direction
 +1 = perfectly positive correlation  values go in opposite direction
 Other formula for Pearson tiorrelatont



Chapter 2
Linear regression
 Determining the approaimately average Y value for a given Xn value
 When dependent variable is quantitative
Diference correlation and regression:
 Correlation is symmetric
o If Xn is correlated to Y, then Y is also correlated to Xn by the same amount
 Regression is asymmetric
o Determining average Y for given Xn is diferent than determining average Xn for
given Y
Independent and dependent variables
 Independent  variable is a cause, value does not depend on another variable
 Dependent  value of variable depends on cause
Designs
 Longitudinal  subject measured repeatedly

,  Cross-sectional  only measured once  no repeated measurements

Regression line
 Summarizes scatter plot by a straight line
 Straight line that minimizes sum of all squared
deviations of observations from regression line
 Useful for calculating e.g. predicted length for age
value
Residuals:
 Deviations of observation from the regression line
Equaton


Deviaton of predicted value from observed Y^ value of
child

Least squares method
 Straight line that minimizes sum of all squared deviations of observations from that
line minimizes sum of squared residuals
 Regression slope:

o
 Regression intercept

o

R-square
 Measure of how good data can be summarized by regression line
 Range is between 0 and 1
o R=1  all of total variation is eaplained by regression line
Total variaton to be explained/total variaton
 Variation


 Denoted as SS(Y) or SS(total)
 Fraction of total variation eaplained by regression line  R-square
Unexplained variaton


 Denoted as SS(residual) or SS(uneaplained)

Dit zijn jouw voordelen als je samenvattingen koopt bij Stuvia:

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

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

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 Jody2711. Stuvia faciliteert de betaling aan de verkoper.

Zit ik meteen vast aan een abonnement?

Nee, je koopt alleen deze samenvatting voor €5,99. 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

Samenvatting

BBS1003-Statistics-Syllabus summary, lectures, videos, Andy Field

Document informatie

Onderwerpen

Gekoppeld boek

Meer samenvattingen voor studieboek

Geschreven voor

Verkoper

Ontvangen beoordelingen

Voorbeeld van de inhoud