\documentclass[10pt,a4paper]{article} % Packages \usepackage{fancyhdr} % For header and footer \usepackage{multicol} % Allows multicols in tables \usepackage{tabularx} % Intelligent column widths \usepackage{tabulary} % Used in header and footer \usepackage{hhline} % Border under tables \usepackage{graphicx} % For images \usepackage{xcolor} % For hex colours %\usepackage[utf8x]{inputenc} % For unicode character support \usepackage[T1]{fontenc} % Without this we get weird character replacements \usepackage{colortbl} % For coloured tables \usepackage{setspace} % For line height \usepackage{lastpage} % Needed for total page number \usepackage{seqsplit} % Splits long words. %\usepackage{opensans} % Can't make this work so far. Shame. Would be lovely. \usepackage[normalem]{ulem} % For underlining links % Most of the following are not required for the majority % of cheat sheets but are needed for some symbol support. \usepackage{amsmath} % Symbols \usepackage{MnSymbol} % Symbols \usepackage{wasysym} % Symbols %\usepackage[english,german,french,spanish,italian]{babel} % Languages % Document Info \author{clarekirk} \pdfinfo{ /Title (soci-271.pdf) /Creator (Cheatography) /Author (clarekirk) /Subject (SOCI 271 Cheat Sheet) } % Lengths and widths \addtolength{\textwidth}{6cm} \addtolength{\textheight}{-1cm} \addtolength{\hoffset}{-3cm} \addtolength{\voffset}{-2cm} \setlength{\tabcolsep}{0.2cm} % Space between columns \setlength{\headsep}{-12pt} % Reduce space between header and content \setlength{\headheight}{85pt} % If less, LaTeX automatically increases it \renewcommand{\footrulewidth}{0pt} % Remove footer line \renewcommand{\headrulewidth}{0pt} % Remove header line \renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit % This two commands together give roughly % the right line height in the tables \renewcommand{\arraystretch}{1.3} \onehalfspacing % Commands \newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour \newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols \newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns \newcommand{\tn}{\tabularnewline} % Required as custom column type in use % Font and Colours \definecolor{HeadBackground}{HTML}{333333} \definecolor{FootBackground}{HTML}{666666} \definecolor{TextColor}{HTML}{333333} \definecolor{DarkBackground}{HTML}{82A397} \definecolor{LightBackground}{HTML}{F7F9F8} \renewcommand{\familydefault}{\sfdefault} \color{TextColor} % Header and Footer \pagestyle{fancy} \fancyhead{} % Set header to blank \fancyfoot{} % Set footer to blank \fancyhead[L]{ \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{C} \SetRowColor{DarkBackground} \vspace{-7pt} {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}} } \end{tabulary} \columnbreak \begin{tabulary}{11cm}{L} \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{SOCI 271 Cheat Sheet}}}} \\ \normalsize{by \textcolor{DarkBackground}{clarekirk} via \textcolor{DarkBackground}{\uline{cheatography.com/144494/cs/31026/}}} \end{tabulary} \end{multicols}} \fancyfoot[L]{ \footnotesize \noindent \begin{multicols}{3} \begin{tabulary}{5.8cm}{LL} \SetRowColor{FootBackground} \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}} \\ \vspace{-2pt}clarekirk \\ \uline{cheatography.com/clarekirk} \\ \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}} \\ \vspace{-2pt}Published 10th March, 2022.\\ Updated 13th March, 2022.\\ Page {\thepage} of \pageref{LastPage}. \end{tabulary} \vfill \columnbreak \begin{tabulary}{5.8cm}{L} \SetRowColor{FootBackground} \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}} \\ \SetRowColor{white} \vspace{-5pt} %\includegraphics[width=48px,height=48px]{dave.jpeg} Measure your website readability!\\ www.readability-score.com \end{tabulary} \end{multicols}} \begin{document} \raggedright \raggedcolumns % Set font size to small. Switch to any value % from this page to resize cheat sheet text: % www.emerson.emory.edu/services/latex/latex_169.html \footnotesize % Small font. \begin{multicols*}{3} \begin{tabularx}{5.377cm}{x{1.34379 cm} x{3.63321 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Probability and Inferential Statistics}} \tn % Row 0 \SetRowColor{LightBackground} {\bf{Parameter }} & A number you derive from a population \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} {\bf{Statistic}} & A number you derive from a sample \tn % Row Count 4 (+ 2) % Row 2 \SetRowColor{LightBackground} {\bf{Census}} & A survey of the whole population \tn % Row Count 6 (+ 2) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Symbols}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646424894_GetImage.png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.9908 cm} x{2.9862 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Probability \& Non-Probability Samples}} \tn % Row 0 \SetRowColor{LightBackground} {\bf{Probability Samples}} & Every case in the population has the same chance of being selected \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} {\bf{Non-Probability Samples}} & A specific group is being used as your sample. {\emph{Surveying students enrolled in a class}} \tn % Row Count 7 (+ 4) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Example}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{We want to know what \% of students work during the semester. \newline % Row Count 2 (+ 2) We draw a sample of 500 from a list of all students at the university \newline % Row Count 4 (+ 2) N = 20,000 (all students at university) \newline % Row Count 5 (+ 1) P = 500/20,000 \newline % Row Count 6 (+ 1) Use a table of random numbers to selected 500 ID numbers with 6 digits \newline % Row Count 8 (+ 2) 6 digits will be chosen 500 times until they match up with student numbers \newline % Row Count 10 (+ 2) After questioning each of these 500 students, we find that 368 (74\%) work during the semester. \newline % Row Count 12 (+ 2) {\bf{Population}} – 20,000 \newline % Row Count 13 (+ 1) {\bf{Sample}} – 500 \newline % Row Count 14 (+ 1) {\bf{Statistic}} – 74\% \newline % Row Count 15 (+ 1) {\bf{Parameter}} – Doesn't directly appear (it's implicit) \newline % Row Count 17 (+ 2) ({\emph{\% of all students in the population who held a job}})% Row Count 19 (+ 2) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.84149 cm} x{3.13551 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Sampling Variation}} \tn % Row 0 \SetRowColor{LightBackground} {\bf{Sample Statistics}} & Variables (e.g., sample mean, sample proportion) \tn % Row Count 2 (+ 2) % Row 1 \SetRowColor{white} {\bf{Sampling Error}} & The sample will differ from the population purely by chance \tn % Row Count 5 (+ 3) % Row 2 \SetRowColor{LightBackground} Positive Sampling Error & Making the statistic exceed the population \tn % Row Count 7 (+ 2) % Row 3 \SetRowColor{white} Negative Sampling Error & Making the statistic less than the population parameter \tn % Row Count 10 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}--} \SetRowColor{LightBackground} \mymulticolumn{2}{x{5.377cm}}{{\emph{Sample statistic = population parameter + sampling error }} \newline \newline {\bf{Sampling Distribution}} \newline The theoretical, probabilistic distribution of a statistic for all possible samples of a given size (n).} \tn \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Construction of a Sampling Distribution}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646943789_Screen Shot 2022-03-10 at 12.22.54 PM.png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\bf{Statistic}} is used to estimate a parameter. \newline Not all statistics will have the same value. \newline {\emph{What is the distribution of the values that we can get for the statistic?}} \newline \newline {\bf{Standard Error}} = population standard error / square root of the population size} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Sampling Distribution}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646944466_Screen Shot 2022-03-10 at 12.34.08 PM.png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Practice Question}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The average age for a population of doctors in a hospital is 51.6 years, What does this mean value represent? \newline % Row Count 3 (+ 3) {\bf{A parameter}} \newline % Row Count 4 (+ 1) What does it mean for a sample to be representative \newline % Row Count 6 (+ 2) {\bf{The sample reproduces the important characteristics of the population}} \newline % Row Count 8 (+ 2) Which set of symbols represents the standard deviation of the sampling distribution? \newline % Row Count 10 (+ 2) Which of these terms is synonymous with the standard error of the mean? \newline % Row Count 12 (+ 2) {\bf{The standard deviation of a sampling distribution}}% Row Count 14 (+ 2) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{1.64241 cm} x{3.33459 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Two Estimation Procedures}} \tn % Row 0 \SetRowColor{LightBackground} Point Estimate & A sample statistic used to estimate a population parameter \tn % Row Count 3 (+ 3) % Row 1 \SetRowColor{white} Confidence Intervals & Consist of a range of values instead of a single point \tn % Row Count 6 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}--} \SetRowColor{LightBackground} \mymulticolumn{2}{x{5.377cm}}{Example of point estimate: \newline 50\% of Canadians drive less because of gas. \newline \newline Example of confidence: \newline Between 47\% and 53\% of Canadian drivers drive less due to high gas prices. \newline \newline {\bf{Confidence Intervals}} \newline - Point estimate is in the middle \newline - Lower and upper bound of C.I: 47\% and 53\% \newline - Margin of Error: radius or spread of the confidence interval (3\%)} \tn \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{x{0.9954 cm} x{3.9816 cm} } \SetRowColor{DarkBackground} \mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Criteria for Choosing Estimators}} \tn % Row 0 \SetRowColor{LightBackground} Bias & An estimator is unbiased if the mean of its sampling distribution is equal to the population value of interest \tn % Row Count 4 (+ 4) % Row 1 \SetRowColor{white} \seqsplit{Efficiency} & The extent to which the sampling distribution is clustered around its mean \tn % Row Count 7 (+ 3) \hhline{>{\arrayrulecolor{DarkBackground}}--} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Bias}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646946013_GetImage (1).png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{If n is large, we know that the sample mean/proportion is equal to the population parameter and: (image) \newline \newline {\bf{Very good}} (68 out of 100 chances) that our sample outcome is within +/- 1 standard deviation of the true population parameter \newline \newline {\bf{Excellent}} (95 out of 100) that it is within +/- 3 standard deviations \newline \newline In less than 1\% of cases, a sample outcome will lie further away than +/- 3 standard deviations} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Efficiency}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646946093_GetImage (2).png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Getting back to the matter of dispersion: standard error σx̄ (standard deviation of the sampling distribution) = σ/(√n) \newline \newline Standard error is an inverse function of n: as sample size increases, σx̄ will decrease \newline \newline The smaller the standard deviation of a sampling distribution, the greater the clustering and the higher the efficiency.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Constructing Confidence Intervals}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{1. Set the alpha, {\emph{a}} \newline % Row Count 1 (+ 1) 2. Find the Z score (or critical value) associated with alpha \newline % Row Count 3 (+ 2) 3. Construct the confidence interval (we will substitute values into the appropriate formulas for confidence interval)% Row Count 6 (+ 3) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Constructing Confidence Intervals - Set the Alpha}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{1. Alpha = the probability that the interval will be wrong, I.e., it doesn't include the population parameter. \newline % Row Count 3 (+ 3) The commonly used alpha level 0.05 corresponds to a 95\% confidence level. \newline % Row Count 5 (+ 2) If an infinite number of intervals were constructed at the 0.50 alpha level (all other things being equal). 95\% of them would contain the population value; 5\% would not.% Row Count 9 (+ 4) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Constructing Confidence Intervals - Find Z Score}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646948925_GetImage (4).png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{For an interval estimate based on +/-1.96 Z's: \newline \newline The probabilities are that 95\% of all such interval will include or overlap the population value \newline \newline We can be 85\% confident that the interval around our one sample outcome contains the population value} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Confidence Interval}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Point Estimate +/- Margin of Error \newline % Row Count 1 (+ 1) Point Estimate +/- (Critical Value * Standard Error)% Row Count 3 (+ 2) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{The margin of error depends on: \newline (1) the standard error for statistic AND \newline (2) a "critical value/Z score" based on the confidence level} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Constructing Confidence Intervals for Proportions}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646949199_GetImage (5).png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{Point Estimate +/- (Critical Value/Score) x Standard Error) \newline \newline {\emph{for large samples (interval estimation for proportions based on small samples) (n\textless{}100) not covered)}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Example}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646949714_GetImage (6).png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{What proportion of students at your university missed at least one day of classes because of illness last semester? \newline \newline Out of a random sample of 200, 60 reported having missed classes: Ps = 60/200 = .30} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Confidence Intervals for Means}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1646949817_GetImage (7).png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{formula for large samples (n≥100)} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Example}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1647022990_GetImage (9).png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{You want to estimate the average IQ of a community using a random sample of 200 residents \newline - with a sample mean IQ of 105 \newline - assuming a population standard deviation for IQ scores of 15 \newline Alpha set at .05 (i.e. we are willing to run a 5\% chance of being wrong). \newline \newline What is the corresponding Z score ? \newline What is the formula?} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Conf}} \tn \SetRowColor{LightBackground} \mymulticolumn{1}{p{5.377cm}}{\vspace{1px}\centerline{\includegraphics[width=5.1cm]{/web/www.cheatography.com/public/uploads/clarekirk_1647023135_Screen Shot 2022-03-11 at 10.24.37 AM.png}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{{\emph{Three differences to Formula 6.1:}} \newline - σ is replaced by s \newline - n is replaced by n–1 to correct for the fact that s is a biased estimator of σ \newline \newline To construct confidence intervals from sample means when s is unknown, we must use a different theoretical distribution, called the {\bf{Student's t distribution.}}} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{T Distribution}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{The shape of the t distribution varies as a function of sample size. \newline % Row Count 2 (+ 2) - Distribution is a family of curves, each curve is defined by its degrees of freedom – a value indicating the number of scores in a sample that are "free to vary" when calculating statistics. \newline % Row Count 7 (+ 5) - {\bf{Degrees of freedom (df = n–1).}} \newline % Row Count 8 (+ 1) - As n increases, s becomes a more and more reliable estimator of the population standard deviation (σ) \newline % Row Count 11 (+ 3) {\emph{t distribution becomes more and more like the Z distribution.}}% Row Count 13 (+ 2) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \SetRowColor{LightBackground} \mymulticolumn{1}{x{5.377cm}}{\{\{ac\}\} Smaller samples: t distribution is flatter and has heavier tails than Z distribution. \newline \newline The Z and t distribution are essentially identical when the sample size is greater than 100.} \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} \begin{tabularx}{5.377cm}{X} \SetRowColor{DarkBackground} \mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{T-Table Practice}} \tn \SetRowColor{white} \mymulticolumn{1}{x{5.377cm}}{Find t score for alpha = 0.05 for n=30 \newline % Row Count 1 (+ 1) Answers: \newline % Row Count 2 (+ 1) Degrees of freedom (df = n-1): 30 – 1 = 29 \newline % Row Count 3 (+ 1) t score: ±2.045% Row Count 4 (+ 1) } \tn \hhline{>{\arrayrulecolor{DarkBackground}}-} \end{tabularx} \par\addvspace{1.3em} % That's all folks \end{multicols*} \end{document}