Kumpulan soal:soal-soal akuntansi perusahaan dagang SOAL SIKLUS AKUNTANSI PERUSAHAAN DAGANG Perusahaan dagang “TaVi Sport” adalah perusahaan dagang yang bergerak dalam bidang penjualan. PENGERTIAN ORGANISASI NIRLABA (NON PROFIT ORIENTED). Demikianlah beberapa contoh soal dan pembahasan statistik. Semoga dari beberapa contoh soal tersebut dapat mewakili materi statistik yang harus teman-teman pelajari sehingga teman-teman dapat memahami materi statistik dengan baik. Semoga bermanfaat dan Selamat Belajar.
Presentation on theme: '1 Pertemuan 13 Regresi Linear dan Korelasi Matakuliah: I0262 – Statistik Probabilitas Tahun: 2007 Versi: Revisi.'— Presentation transcript:
1 1 Pertemuan 13 Regresi Linear dan Korelasi Matakuliah: I0262 – Statistik Probabilitas Tahun: 2007 Versi: Revisi
2 2 Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : Mahasiswa akan dapat memilih statistik uji untuk koefisien regresi dan korelasi.
3 3 Outline Materi Pengujian koefisien regresi dengan analisis varians Inferensia tentang koefisien korelasi
4 4 Testing for Significance To test for a significant regression relationship, we must conduct a hypothesis test to determine whether the value of 1 is zero. Two tests are commonly used –t Test –F Test Both tests require an estimate of 2, the variance of in the regression model.
5 5 Testing for Significance An Estimate of 2 The mean square error (MSE) provides the estimate of 2, and the notation s 2 is also used. s 2 = MSE = SSE/(n-2) where:
6 6 Testing for Significance An Estimate of –To estimate we take the square root of 2. –The resulting s is called the standard error of the estimate.
7 7 Hypotheses H 0 : 1 = 0 H a : 1 = 0 Test Statistic Rejection Rule Reject H 0 if t t where t is based on a t distribution with n - 2 degrees of freedom. Testing for Significance: t Test
Contoh Soal Statistika Bisnis
8 8 t Test –Hypotheses H 0 : 1 = 0 H a : 1 = 0 –Rejection Rule For =.05 and d.f. = 3, t.025 = 3.182 Reject H 0 if t > 3.182 –Test Statistics t = 5/1.08 = 4.63 –Conclusions Reject H 0 Contoh Soal: Reed Auto Sales
9 9 Confidence Interval for 1 We can use a 95% confidence interval for 1 to test the hypotheses just used in the t test. H 0 is rejected if the hypothesized value of 1 is not included in the confidence interval for 1.
10 10 Confidence Interval for 1 The form of a confidence interval for 1 is: where b 1 is the point estimate is the margin of error is the t value providing an area of /2 in the upper tail of a t distribution with n - 2 degrees of freedom
11 11 Contoh Soal: Reed Auto Sales Rejection Rule Reject H 0 if 0 is not included in the confidence interval for 1. 95% Confidence Interval for 1 = 5 +- 3.182(1.08) = 5 +- 3.44 /or 1.56 to 8.44/ Conclusion Reject H 0
12 12 Testing for Significance: F Test n Hypotheses H 0 : 1 = 0 H 0 : 1 = 0 H a : 1 = 0 H a : 1 = 0 n Test Statistic F = MSR/MSE n Rejection Rule Reject H 0 if F > F where F is based on an F distribution with 1 d.f. in the numerator and n - 2 d.f. in the denominator.
13 13 n F Test Hypotheses H 0 : 1 = 0 Hypotheses H 0 : 1 = 0 H a : 1 = 0 H a : 1 = 0 Rejection Rule Rejection Rule For =.05 and d.f. = 1, 3: F.05 = 10.13 For =.05 and d.f. = 1, 3: F.05 = 10.13 Reject H 0 if F > 10.13. Reject H 0 if F > 10.13. Test Statistic Test Statistic F = MSR/MSE = 100/4.667 = 21.43 Conclusion Conclusion We can reject H 0. Example: Reed Auto Sales
14 14 Some Cautions about the Interpretation of Significance Tests Rejecting H 0 : 1 = 0 and concluding that the relationship between x and y is significant does not enable us to conclude that a cause-and-effect relationship is present between x and y. Just because we are able to reject H 0 : 1 = 0 and demonstrate statistical significance does not enable us to conclude that there is a linear relationship between x and y.
15 15 n Confidence Interval Estimate of E ( y p ) n Prediction Interval Estimate of y p y p + t /2 s ind y p + t /2 s ind where the confidence coefficient is 1 - and t /2 is based on a t distribution with n - 2 d.f. Using the Estimated Regression Equation for Estimation and Prediction
16 16 Point Estimation If 3 TV ads are run prior to a sale, we expect the mean number of cars sold to be: y = 10 + 5(3) = 25 cars Confidence Interval for E(y p ) 95% confidence interval estimate of the mean number of cars sold when 3 TV ads are run is: 25 + 4.61 = 20.39 to 29.61 cars Prediction Interval for y p 95% prediction interval estimate of the number of cars sold in one particular week when 3 TV ads are run is: 25 + 8.28 = 16.72 to 33.28 cars ^ Contoh Soal: Reed Auto Sales
17 17 Residual for Observation i y i – y i Standardized Residual for Observation i where: Residual Analysis ^^^^
Contoh Soal Dan Pembahasan Statistika
18 18 Contoh Soal: Reed Auto Sales Residuals
19 19 Contoh Soal: Reed Auto Sales Residual Plot
Contoh Soal Statistik Parametrik
20 20 Residual Analysis Detecting Outliers – An outlier is an observation that is unusual in comparison with the other data. – Minitab classifies an observation as an outlier if its standardized residual value is +2. – This standardized residual rule sometimes fails to identify an unusually large observation as being an outlier. – This rule’s shortcoming can be circumvented by using studentized deleted residuals. – The i th studentized deleted residual will be larger than the i th standardized residual .
21 21 Selamat Belajar Semoga Sukses.