IT 403 Statistics and Data Analysis Final Review Guide

Transcription

1 IT 403 Statistics and Data Analysis Final Review Guide Exam Schedule and Format Date: 11/15 (Wed) for Section 702 (Loop); between 11/15 (Wed) and 11/18 (Sat) for Section 711 (Online). Location: CDM 224 for Section 702; individually arranged location for Section 711. Time: 2.5 hours -- 5:45 8:15 pm for Section 702; proctored 2.5-hour exam for Section 711. Format: Pencil-and-paper. You write answers on the exam paper. No computer is allowed. But ONE letter-size sheet of note is allowed (written on both sides). A calculator is allowed. Phones are allowed ONLY IF they are used as a calculator. Any other uses of phones are strictly prohibited. The Standard Normal table, the t-table and a sheet of basic formulas (the next page) will be separately provided (as appendices to the exam paper). You prepare any other formulas on your sheet. Formats of Questions Multiple choice (with or without showing work, in addition to the choice) Short answer (numeric calculation or comments/description typically as a follow-up question) Full problems (e.g. hypothesis tests) Topics Comprehensive, from the begiing till 8.2 (Comparing Two Proportions). Below are relevant textbook sections: o Ch , 1.2, 1.3, 1.4 o Ch , 2.2 (exclude log transformation on), 2.3, 2.4, 2.5, 2.7 o Ch , 3.2 (exclude block designs on), 3.3 (exclude stratified random samples on) o Ch , 4.2, 4.3, 4.4 o Ch , 5.2 (exclude Weibull distributions on), 5.3 (exclude Continuity correction and Poisson distributions on) o Ch , 6.2 o Ch , 7.2 (exclude inference for small samples, software approximation for the df ; but include pooled two-sample t-procedures ) o Ch (exclude Plus Four CI and choosing a sample size for a CI on), 8.2 (exclude choosing a sample size for two sample proportions on)

2 Symbols µ population mean σσ 2 population variance σ population standard deviation xx sample mean s sample standard deviation (divided by n-1) pp sample proportion Q0 minimum in a sample Q1 1 st quartile = 25 th percentile Q2 2 nd quartile = 50 th percentile = median Q3 3 rd quartile = 75 th percentile Q4 maximum in a sample Formulas Interquartile Range: IQR = Q3 - Q1 1.5 x IQR rule for outliers: Q1-1.5 IQR; Q IQR Sample standard deviation: ss = 1 1 (xx ii xx ) 2 z-score for individual observations: zz = xx ii xx Correlation coefficient: rr = 1 1 xx ii xx ss xx ss yy yy ss yy Least-square linear regression equation: yy = bb 0 + bb 1 xx where bb 1 = rr ss yy ss xx and bb 0 = yy bb 1 xx Mean and standard deviation of a discrete random variable: μμ XX = xx ii pp ii, σσ XX = (xx ii μμ XX ) 2 pp ii Probability: For a sample space S, PP(SS) = 1 Probability - Addition rule: if A and B are disjoint events, PP(AA BB) = PP(AA) + PP(BB) Probability - Multiplication rule: if A and B are independent events, PP(AA BB) = PP(AA) PP(BB) Binomial probability: PP(XX = kk) =! kk! ( kk)! ppkk (1 pp) kk, for binomial distribution B(n, p) Confidence interval: (estimate) ± (critical value) (standard error) Sample mean (xx ) - Mean: μμ xx = μμ Sample mean (xx ) Standard deviation: σσ xx = σσ when σσ is known or n is large Sample mean (xx ) Standard error: SSSS xx = ss Test statistic (z-score or t-score) for xx : zz = (xx μμ), tt = (xx μμ) when σσ is not known or n is small Sample proportion (pp ): pp = XX, where X is the count of successes in n trials SSSS xx Sample proportion (pp ) Standard error: SSSS pp = pp (1 pp ) Test statistic (z-score) for pp : zz = pp pp 0 pp 0 (1 pp0) SSSS xx, where p 0 is the value assumed in the null hypothesis

3 T-2 Probability Table entry for z is the area under the standard normal curve to the left of z. z TABLE A Standard normal probabilities z

4 T-3 Probability Table entry for z is the area under the standard normal curve to the left of z. z TABLE A Standard normal probabilities (continued) z

5 T-11 Table entry for p and C is the critical value t with probability p lying to its right and probability C lying between t and t. TABLE D t distribution critical values t* Probability p Upper-tail probability p df z % 60% 70% 80% 90% 95% 96% 98% 99% 99.5% 99.8% 99.9% Confidence level C