40 lines
1.4 KiB
Kotlin
40 lines
1.4 KiB
Kotlin
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package com.baeldung.simplelinearregression
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import org.junit.Assert.assertEquals
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import org.junit.jupiter.api.Test
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class SimpleLinearRegressionUnitTest {
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@Test
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fun givenAProperDataSetWhenFedToASimpleLinearRegressionModelThenItPredictsCorrectly() {
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val xs = arrayListOf(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
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val ys = arrayListOf(25, 35, 49, 60, 75, 90, 115, 130, 150, 200)
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val model = SimpleLinearRegression(xs, ys)
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val predictionOne = model.predict(2.5)
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assertEquals(38.99, predictionOne, 0.01)
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val predictionTwo = model.predict(7.5)
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assertEquals(128.84, predictionTwo, 0.01)
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}
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@Test
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fun givenAPredictableDataSetWhenCalculatingTheLossFunctionThenTheModelIsConsideredReliable() {
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val xs = arrayListOf(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
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val ys = arrayListOf(25, 35, 49, 60, 75, 90, 115, 130, 150, 200)
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val model = SimpleLinearRegression(xs, ys)
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assertEquals(0.95, model.calculateRSquared(), 0.01)
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}
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@Test
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fun givenAnUnpredictableDataSetWhenCalculatingTheLossFunctionThenTheModelIsConsideredUnreliable() {
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val xs = arrayListOf(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
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val ys = arrayListOf(200, 0, 200, 0, 0, 0, -115, 1000, 0, 1)
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val model = SimpleLinearRegression(xs, ys)
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assertEquals(0.01, model.calculateRSquared(), 0.01)
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}
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}
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