机器算法验证 - 保留每周平均值的流感数据插值 - 吾爱随笔录

保留每周平均值的流感数据插值

机器算法验证 r 时间序列插值

2022-01-25 11:05:40

编辑

我找到了一篇论文，准确地描述了我需要的程序。唯一的区别是本文将月平均数据插入到每日数据，同时保留了月平均数据。我很难在R. 任何提示表示赞赏。

原来的

对于每周，我有以下计数数据（每周一个值）：

就诊次数
流感病例数

我的目标是通过插值获得每日数据（我想到了线性或截断样条）。重要的是我想保留每周平均值，即每日插值数据的平均值应该等于本周的记录值。此外，插值应该是平滑的。可能出现的一个问题是某一周的天数少于 7 天（例如，在一年的开始或结束时）。

我将不胜感激有关此问题的建议。

非常感谢。

这是 1995 年的示例数据集（更新）：

structure(list(daily.ts = structure(c(9131, 9132, 9133, 9134, 
9135, 9136, 9137, 9138, 9139, 9140, 9141, 9142, 9143, 9144, 9145, 
9146, 9147, 9148, 9149, 9150, 9151, 9152, 9153, 9154, 9155, 9156, 
9157, 9158, 9159, 9160, 9161, 9162, 9163, 9164, 9165, 9166, 9167, 
9168, 9169, 9170, 9171, 9172, 9173, 9174, 9175, 9176, 9177, 9178, 
9179, 9180, 9181, 9182, 9183, 9184, 9185, 9186, 9187, 9188, 9189, 
9190, 9191, 9192, 9193, 9194, 9195, 9196, 9197, 9198, 9199, 9200, 
9201, 9202, 9203, 9204, 9205, 9206, 9207, 9208, 9209, 9210, 9211, 
9212, 9213, 9214, 9215, 9216, 9217, 9218, 9219, 9220, 9221, 9222, 
9223, 9224, 9225, 9226, 9227, 9228, 9229, 9230, 9231, 9232, 9233, 
9234, 9235, 9236, 9237, 9238, 9239, 9240, 9241, 9242, 9243, 9244, 
9245, 9246, 9247, 9248, 9249, 9250, 9251, 9252, 9253, 9254, 9255, 
9256, 9257, 9258, 9259, 9260, 9261, 9262, 9263, 9264, 9265, 9266, 
9267, 9268, 9269, 9270, 9271, 9272, 9273, 9274, 9275, 9276, 9277, 
9278, 9279, 9280, 9281, 9282, 9283, 9284, 9285, 9286, 9287, 9288, 
9289, 9290, 9291, 9292, 9293, 9294, 9295, 9296, 9297, 9298, 9299, 
9300, 9301, 9302, 9303, 9304, 9305, 9306, 9307, 9308, 9309, 9310, 
9311, 9312, 9313, 9314, 9315, 9316, 9317, 9318, 9319, 9320, 9321, 
9322, 9323, 9324, 9325, 9326, 9327, 9328, 9329, 9330, 9331, 9332, 
9333, 9334, 9335, 9336, 9337, 9338, 9339, 9340, 9341, 9342, 9343, 
9344, 9345, 9346, 9347, 9348, 9349, 9350, 9351, 9352, 9353, 9354, 
9355, 9356, 9357, 9358, 9359, 9360, 9361, 9362, 9363, 9364, 9365, 
9366, 9367, 9368, 9369, 9370, 9371, 9372, 9373, 9374, 9375, 9376, 
9377, 9378, 9379, 9380, 9381, 9382, 9383, 9384, 9385, 9386, 9387, 
9388, 9389, 9390, 9391, 9392, 9393, 9394, 9395, 9396, 9397, 9398, 
9399, 9400, 9401, 9402, 9403, 9404, 9405, 9406, 9407, 9408, 9409, 
9410, 9411, 9412, 9413, 9414, 9415, 9416, 9417, 9418, 9419, 9420, 
9421, 9422, 9423, 9424, 9425, 9426, 9427, 9428, 9429, 9430, 9431, 
9432, 9433, 9434, 9435, 9436, 9437, 9438, 9439, 9440, 9441, 9442, 
9443, 9444, 9445, 9446, 9447, 9448, 9449, 9450, 9451, 9452, 9453, 
9454, 9455, 9456, 9457, 9458, 9459, 9460, 9461, 9462, 9463, 9464, 
9465, 9466, 9467, 9468, 9469, 9470, 9471, 9472, 9473, 9474, 9475, 
9476, 9477, 9478, 9479, 9480, 9481, 9482, 9483, 9484, 9485, 9486, 
9487, 9488, 9489, 9490, 9491, 9492, 9493, 9494, 9495), class = "Date"), 
    wdayno = c(0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 
    5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 
    6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 
    0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 
    1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 
    2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 
    3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 
    4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 
    5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 
    6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 
    0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 
    1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 
    2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 
    3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 
    4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 
    5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 
    6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 
    0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 
    1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 
    2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 
    3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 
    4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 
    5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 
    6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L, 1L, 2L, 3L, 4L, 5L, 6L, 
    0L, 1L, 2L, 3L, 4L, 5L, 6L, 0L), month = c(1, 1, 1, 1, 1, 
    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
    1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 
    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 
    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 
    3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 
    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 
    4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 
    5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 
    6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 
    6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
    7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 
    8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 
    8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 
    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 
    9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 
    10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 
    10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 
    11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 
    11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 
    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 
    12, 12, 12, 12), year = c(1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 
    1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995, 1995), yearday = 0:364, 
    no.influ.cases = c(NA, NA, NA, 168L, NA, NA, NA, NA, NA, 
    NA, 199L, NA, NA, NA, NA, NA, NA, 214L, NA, NA, NA, NA, NA, 
    NA, 230L, NA, NA, NA, NA, NA, NA, 267L, NA, NA, NA, NA, NA, 
    NA, 373L, NA, NA, NA, NA, NA, NA, 387L, NA, NA, NA, NA, NA, 
    NA, 443L, NA, NA, NA, NA, NA, NA, 579L, NA, NA, NA, NA, NA, 
    NA, 821L, NA, NA, NA, NA, NA, NA, 1229L, NA, NA, NA, NA, 
    NA, NA, 1014L, NA, NA, NA, NA, NA, NA, 831L, NA, NA, NA, 
    NA, NA, NA, 648L, NA, NA, NA, NA, NA, NA, 257L, NA, NA, NA, 
    NA, NA, NA, 203L, NA, NA, NA, NA, NA, NA, 137L, NA, NA, NA, 
    NA, NA, NA, 78L, NA, NA, NA, NA, NA, NA, 82L, NA, NA, NA, 
    NA, NA, NA, 69L, NA, NA, NA, NA, NA, NA, 45L, NA, NA, NA, 
    NA, NA, NA, 51L, NA, NA, NA, NA, NA, NA, 45L, NA, NA, NA, 
    NA, NA, NA, 63L, NA, NA, NA, NA, NA, NA, 55L, NA, NA, NA, 
    NA, NA, NA, 54L, NA, NA, NA, NA, NA, NA, 52L, NA, NA, NA, 
    NA, NA, NA, 27L, NA, NA, NA, NA, NA, NA, 24L, NA, NA, NA, 
    NA, NA, NA, 12L, NA, NA, NA, NA, NA, NA, 10L, NA, NA, NA, 
    NA, NA, NA, 22L, NA, NA, NA, NA, NA, NA, 42L, NA, NA, NA, 
    NA, NA, NA, 32L, NA, NA, NA, NA, NA, NA, 52L, NA, NA, NA, 
    NA, NA, NA, 82L, NA, NA, NA, NA, NA, NA, 95L, NA, NA, NA, 
    NA, NA, NA, 91L, NA, NA, NA, NA, NA, NA, 104L, NA, NA, NA, 
    NA, NA, NA, 143L, NA, NA, NA, NA, NA, NA, 114L, NA, NA, NA, 
    NA, NA, NA, 100L, NA, NA, NA, NA, NA, NA, 83L, NA, NA, NA, 
    NA, NA, NA, 113L, NA, NA, NA, NA, NA, NA, 145L, NA, NA, NA, 
    NA, NA, NA, 175L, NA, NA, NA, NA, NA, NA, 222L, NA, NA, NA, 
    NA, NA, NA, 258L, NA, NA, NA, NA, NA, NA, 384L, NA, NA, NA, 
    NA, NA, NA, 755L, NA, NA, NA, NA, NA, NA, 976L, NA, NA, NA, 
    NA, NA, NA, 879L, NA, NA, NA, NA), no.consultations = c(NA, 
    NA, NA, 15093L, NA, NA, NA, NA, NA, NA, 20336L, NA, NA, NA, 
    NA, NA, NA, 20777L, NA, NA, NA, NA, NA, NA, 21108L, NA, NA, 
    NA, NA, NA, NA, 20967L, NA, NA, NA, NA, NA, NA, 20753L, NA, 
    NA, NA, NA, NA, NA, 18782L, NA, NA, NA, NA, NA, NA, 19778L, 
    NA, NA, NA, NA, NA, NA, 19223L, NA, NA, NA, NA, NA, NA, 21188L, 
    NA, NA, NA, NA, NA, NA, 22172L, NA, NA, NA, NA, NA, NA, 21965L, 
    NA, NA, NA, NA, NA, NA, 21768L, NA, NA, NA, NA, NA, NA, 21277L, 
    NA, NA, NA, NA, NA, NA, 16383L, NA, NA, NA, NA, NA, NA, 15337L, 
    NA, NA, NA, NA, NA, NA, 19179L, NA, NA, NA, NA, NA, NA, 18705L, 
    NA, NA, NA, NA, NA, NA, 19623L, NA, NA, NA, NA, NA, NA, 19363L, 
    NA, NA, NA, NA, NA, NA, 16257L, NA, NA, NA, NA, NA, NA, 19219L, 
    NA, NA, NA, NA, NA, NA, 17048L, NA, NA, NA, NA, NA, NA, 19231L, 
    NA, NA, NA, NA, NA, NA, 20023L, NA, NA, NA, NA, NA, NA, 19331L, 
    NA, NA, NA, NA, NA, NA, 18995L, NA, NA, NA, NA, NA, NA, 16571L, 
    NA, NA, NA, NA, NA, NA, 15010L, NA, NA, NA, NA, NA, NA, 13714L, 
    NA, NA, NA, NA, NA, NA, 10451L, NA, NA, NA, NA, NA, NA, 14216L, 
    NA, NA, NA, NA, NA, NA, 16800L, NA, NA, NA, NA, NA, NA, 18305L, 
    NA, NA, NA, NA, NA, NA, 18911L, NA, NA, NA, NA, NA, NA, 17812L, 
    NA, NA, NA, NA, NA, NA, 18665L, NA, NA, NA, NA, NA, NA, 18977L, 
    NA, NA, NA, NA, NA, NA, 19512L, NA, NA, NA, NA, NA, NA, 17424L, 
    NA, NA, NA, NA, NA, NA, 14464L, NA, NA, NA, NA, NA, NA, 16383L, 
    NA, NA, NA, NA, NA, NA, 19916L, NA, NA, NA, NA, NA, NA, 18255L, 
    NA, NA, NA, NA, NA, NA, 20113L, NA, NA, NA, NA, NA, NA, 20084L, 
    NA, NA, NA, NA, NA, NA, 20196L, NA, NA, NA, NA, NA, NA, 20184L, 
    NA, NA, NA, NA, NA, NA, 20261L, NA, NA, NA, NA, NA, NA, 22246L, 
    NA, NA, NA, NA, NA, NA, 23030L, NA, NA, NA, NA, NA, NA, 10487L, 
    NA, NA, NA, NA)), .Names = c("daily.ts", "wdayno", "month", 
"year", "yearday", "no.influ.cases", "no.consultations"), row.names = c(NA, 
-365L), class = "data.frame")

4个回答

我设法创建了一个R函数，它可以线性地和样条线插值均匀间隔的点，同时保留平均值（例如每周、每月等）。它使用包中的函数na.approx和迭代计算具有所需属性的样条线。该算法在本文中进行了描述。na.splinezoo

这是代码：

interpol.consmean <- function(y, period=7, max.iter=100, tol=1e-4, plot=FALSE) {

  require(zoo)

  if( plot == TRUE ) {
    require(ggplot2)
  }

  y.temp.linear <- matrix(NA, ncol=length(y), nrow=max.iter+1)
  y.temp.linear[1, ] <- y

  y.temp.spline <- y.temp.linear

  y.temp.pred.spline <- matrix(NA, ncol=length(y), nrow=max.iter)
  y.temp.pred.linear <- matrix(NA, ncol=length(y), nrow=max.iter)

  ind.actual <- which(!is.na(y))

  if ( !all(diff(ind.actual)[1]== diff(ind.actual)) ) {
    stop("\"y\" must contain an evenly spaced time series")
  }

  partial <- ifelse((length(y) - ind.actual[length(ind.actual)]) < period/2,
                    TRUE, FALSE)

  for(k in 1:max.iter) {

    y.temp.pred.linear[k,] <- na.approx(y.temp.linear[k, ], na.rm=FALSE, rule=2)
    y.temp.pred.spline[k,] <- na.spline(y.temp.spline[k, ], method="fmm")

    interpol.means.linear <- rollapply(y.temp.pred.linear[k,], width=period, mean,
                                       by=period, align="left", partial=partial) 
    interpol.means.splines <- rollapply(y.temp.pred.spline[k,], width=period, mean,
                                        by=period, align="left", partial=partial) 

    resid.linear <- y.temp.linear[k, ][ ind.actual ] - interpol.means.linear
    resid.spline <- y.temp.spline[k, ][ ind.actual ] - interpol.means.splines

    if ( max(resid.linear, na.rm=TRUE) < tol & max(resid.spline, na.rm=TRUE) < tol ){
      cat("Converged after", k, "iterations with tolerance of", tol, sep=" ")
      break
    }

    y.temp.linear[k+1, ][!is.na(y.temp.linear[k, ])] <-  resid.linear
    y.temp.spline[k+1, ][!is.na(y.temp.spline[k, ])] <-  resid.spline

  }  

  interpol.linear.final <- colSums(y.temp.pred.linear, na.rm=TRUE)
  interpol.spline.final <- colSums(y.temp.pred.spline, na.rm=TRUE)

  if ( plot == TRUE ) {

    plot.frame <- data.frame(
      y=rep(y,2)/7,
      x=rep(1:length(y),2),
      inter.values=c(interpol.linear.final, interpol.spline.final)/7,
      method=c(rep("Linear", length(y)), rep("Spline", length(y)))
    )

    p <- ggplot(data=plot.frame, aes(x=x)) +
      geom_point(aes(y=y, x=x), size=4) +
      geom_line(aes(y=inter.values, color=method), size=1) +
      ylab("y") +
      xlab("x") +
      theme(axis.title.y =element_text(vjust=0.4, size=20, angle=90)) +
      theme(axis.title.x =element_text(vjust=0, size=20, angle=0)) +
      theme(axis.text.x =element_text(size=15, colour = "black")) +
      theme(axis.text.y =element_text(size=17, colour = "black")) +
      theme(panel.background =  element_rect(fill = "grey85", colour = NA),
            panel.grid.major =  element_line(colour = "white"),
            panel.grid.minor =  element_line(colour = "grey90", size = 0.25))+
      scale_color_manual(values=c("#377EB8", "#E41A1C"), 
                         name="Interpolation method",
                         breaks=c("Linear", "Spline"),
                         labels=c("Linear", "Spline")) +
      theme(legend.position="none") +
      theme(strip.text.x = element_text(size=16)) +
      facet_wrap(~ method)

    suppressWarnings(print(p))

  }
  list(linear=interpol.linear.final, spline=interpol.spline.final)
}

让我们将该函数应用于问题中给出的示例数据集：

interpolations <- interpol.consmean(y=dat.frame$no.influ.cases, period=7,
                                    max.iter = 100, tol=1e-6, plot=TRUE)

线性和样条插值看起来都很好。让我们检查是否保留了每周平均值（截断输出）：

cbind(dat.frame$no.influ.cases[!is.na(dat.frame$no.influ.cases)],
      rollapply(interpolations$linear, 7, mean, by=7, align="left", partial=F))

      [,1] [,2]
 [1,]  168  168
 [2,]  199  199
 [3,]  214  214
 [4,]  230  230
 [5,]  267  267
 [6,]  373  373
 [7,]  387  387
 [8,]  443  443
 [9,]  579  579
[10,]  821  821
[11,] 1229 1229

在范围中点通过平均值的任何直线都将产生具有所需平均值的每日值。尼克考克斯关于“将每周计数除以天数”的最后评论是梯度 = 0 的特例。

所以我们可以调整它并选择渐变以使事情变得更平滑一些。这是执行类似操作的三个 R 函数：

interpwk <- function(x,y,delta){
  offset=-3:3
  yout=y+delta*offset
  xout=x+offset
  cbind(xout,yout)
}

get_delta <- function(x,y,pos){
  (y[pos+1]-y[pos-1])/(x[pos+1]-x[pos-1])
}

#' get slope from neighbours
interpall <- function(x,y,delta1,f=1){
  for(i in 2:(length(x)-1)){
    delta=get_delta(x,y,i)
    xyout=interpwk(x[i],y[i],delta/f)
    points(xyout)
  }
}

为您的数据添加一个日期度量，然后绘制，然后绘制插值器：

> data$day=data$week*7
> plot(data$day,data$no.influ.cases,type="l")
> interpall(data$day,data$no.influ.cases,f=1)

线性均值保持插值器

另一种可能性是在周末限制连续性，但这为您提供了一个只有一个自由度的系统 - 即它完全由第一部分的斜率定义（因为所有其他部分都必须连接起来）。我没有对此进行编码 - 你可以试试！

[Apols 用于略显破旧的 R 代码，它应该真正返回点而不是绘制它们]

我认为，由于您正在处理计数，您可以将每日计数建模为多项式， $n$ 是一周的总数；可以在 GLM 中进行样条平滑。

（如果数据是测量值而不是计数，我倾向于通过 Dirichlet 模型对比例进行建模，但这稍微复杂一些。）

天数并不总是相同的事实不应该是一个特别的问题，只要您知道它是什么 - 只要您使用偏移量将事物置于相同的“水平”。

我会将一些额外的评论捆绑在一起作为另一个答案。

这个项目的结构需要一段时间才能变得更加清晰。鉴于流感现在被揭示为几个协变量中的一个，那么你所做的一切似乎并不那么重要，或者至少不值得我在之前的一些评论中表达的怀疑态度。由于其他所有事情都是每天进行的，因此将其他所有事情减少到几周会丢掉太多细节。

问题的最初焦点仍然是保留每周平均值的插值，其中一个（极端）答案是每周平均值保留每周平均值。不出所料，这似乎没有吸引力或不切实际，其他插值方法似乎更有吸引力和/或由@Spacedman 提出的插补方法。（我不清楚这是否会是具有时间风味的插值或具有附加随机风味的插值。）

两个更具体的想法：

取每周值（除以天数），然后用加权平均值进行平滑处理，在实践中可能会将平均值保持在一个很好的近似值。
由于流感病例是计数，因此平滑根或对数计数然后进行反向转换可能比仅平滑计数更好。

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