Cardinality and frequency estimation - CS 591 K1: Data Stream Processing and Analytics Spring 2020Processing and Analytics Vasiliki (Vasia) Kalavri vkalavri@bu.edu Spring 2020 4/23: Cardinality and frequency estimation ??? Vasiliki Kalavri | Boston University 2020 Counting distinct elements 2 University 2020 LogLog algorithm Input: stream S, array of m counters, hash fiction h Output: cardinality of S for j=0 to m-1 do: COUNT[j] = 0 for x in S do: i = h(x) j = getLeftBits(i, p) r = Boston University 2020 26 • Query approximation error • Error probability Guarantee: The estimation error for frequencies will not exceed with probability • A higher number of hash functions0 码力 | 69 页 | 630.01 KB | 1 年前3
pandas: powerful Python data analysis toolkit - 0.12Release 0.12.0 Example above is the same as previous except the plot is set to kernel density estimation. This shows how easy it is to have different plots for the same Trellis structure. In [12]: plt Python data analysis toolkit, Release 0.12.0 Above is a similar plot but with 2D kernel desnity estimation plot superimposed. In [24]: plt.figure()In [25]: plot relative weightings (viewing EWMA as a moving average) bias : boolean, default False Use a standard estimation bias correction Returns y : type of input argument 472 Chapter 25. API Reference pandas: powerful 0 码力 | 657 页 | 3.58 MB | 1 年前3
Lecture 4: Regularization and Bayesian Statisticssatisfied Feng Li (SDU) Regularization and Bayesian Statistics September 20, 2023 11 / 25 Parameter Estimation in Probabilistic Models Assume data are generated via probabilistic model d ∼ p(d; θ) p(d; θ): Regularization and Bayesian Statistics September 20, 2023 12 / 25 Maximum Likelihood Estimation (MLE) Maximum Likelihood Estimation (MLE): Choose the parameter θ that maximizes the probability of the data, given parameter estimation θMLE = arg max θ ℓ(θ) = arg max θ m � i=1 log p(d(i); θ) Feng Li (SDU) Regularization and Bayesian Statistics September 20, 2023 13 / 25 Maximum-a-Posteriori Estimation (MAP)0 码力 | 25 页 | 185.30 KB | 1 年前3
pandas: powerful Python data analysis toolkit - 0.14.0having absolute values which are greater than one, and/or a non-invertible covariance matrix. See Estimation of covariance matrices for more details. In [8]: frame = DataFrame(randn(1000, 5), columns=[’a’ Release 0.14.0 Example above is the same as previous except the plot is set to kernel density estimation. This shows how easy it is to have different plots for the same Trellis structure. In [12]: plt Python data analysis toolkit, Release 0.14.0 Above is a similar plot but with 2D kernel desnity estimation plot superimposed. In [24]: plt.figure() Out[24]:In 0 码力 | 1349 页 | 7.67 MB | 1 年前3
pandas: powerful Python data analysis toolkit - 0.13.1Release 0.13.1 Example above is the same as previous except the plot is set to kernel density estimation. This shows how easy it is to have different plots for the same Trellis structure. In [12]: plt Python data analysis toolkit, Release 0.13.1 Above is a similar plot but with 2D kernel desnity estimation plot superimposed. In [24]: plt.figure() Out[24]:In relative weightings (viewing EWMA as a moving average) bias : boolean, default False Use a standard estimation bias correction Returns y : type of input argument Notes Either center of mass or span must 0 码力 | 1219 页 | 4.81 MB | 1 年前3
pandas: powerful Python data analysis toolkit - 0.15having absolute values which are greater than one, and/or a non-invertible covariance matrix. See Estimation of covariance matrices for more details. In [8]: frame = DataFrame(randn(1000, 5), columns=[’a’ at 0xa42e05cc> Example above is the same as previous except the plot is set to kernel density estimation. This shows how easy it is to have different plots for the same Trellis structure. In [196]: plt Out[207]:Above is a similar plot but with 2D kernel density estimation plot superimposed. In [208]: plt.figure() Out[208]: 0 码力 | 1579 页 | 9.15 MB | 1 年前3
pandas: powerful Python data analysis toolkit - 0.15.1having absolute values which are greater than one, and/or a non-invertible covariance matrix. See Estimation of covariance matrices for more details. In [8]: frame = DataFrame(randn(1000, 5), columns=[’a’ at 0xa473c24c> Example above is the same as previous except the plot is set to kernel density estimation. This shows how easy it is to have different plots for the same Trellis structure. In [196]: plt Out[207]:Above is a similar plot but with 2D kernel density estimation plot superimposed. In [208]: plt.figure() Out[208]: 0 码力 | 1557 页 | 9.10 MB | 1 年前3
pandas: powerful Python data analysis toolkit - 1.0.0having absolute values which are greater than one, and/or a non-invertible covariance matrix. See Estimation of covariance matrices for more details. In [8]: frame = pd.DataFrame(np.random.randn(1000, 5) especially true for text data columns with relatively few unique values (commonly referred to as “low-cardinality” data). By using more efficient data types, you can store larger datasets in memory. In [6]: ts powerful Python data analysis toolkit, Release 1.0.0 • ‘box’ : boxplot • ‘kde’ : Kernel Density Estimation plot • ‘density’ : same as ‘kde’ • ‘area’ : area plot • ‘pie’ : pie plot • ‘scatter’ : scatter0 码力 | 3015 页 | 10.78 MB | 1 年前3
pandas: powerful Python data analysis toolkit - 1.0having absolute values which are greater than one, and/or a non-invertible covariance matrix. See Estimation of covariance matrices for more details. In [8]: frame = pd.DataFrame(np.random.randn(1000, 5) especially true for text data columns with relatively few unique values (commonly referred to as “low-cardinality” data). By using more efficient data types, you can store larger datasets in memory. In [6]: ts powerful Python data analysis toolkit, Release 1.0.5 • ‘box’ : boxplot • ‘kde’ : Kernel Density Estimation plot • ‘density’ : same as ‘kde’ • ‘area’ : area plot • ‘pie’ : pie plot • ‘scatter’ : scatter0 码力 | 3091 页 | 10.16 MB | 1 年前3
pandas: powerful Python data analysis toolkit - 1.0.4having absolute values which are greater than one, and/or a non-invertible covariance matrix. See Estimation of covariance matrices for more details. In [8]: frame = pd.DataFrame(np.random.randn(1000, 5) especially true for text data columns with relatively few unique values (commonly referred to as “low-cardinality” data). By using more efficient data types, you can store larger datasets in memory. In [6]: ts powerful Python data analysis toolkit, Release 1.0.4 • ‘box’ : boxplot • ‘kde’ : Kernel Density Estimation plot • ‘density’ : same as ‘kde’ • ‘area’ : area plot • ‘pie’ : pie plot • ‘scatter’ : scatter0 码力 | 3081 页 | 10.24 MB | 1 年前3
共 61 条
- 1
- 2
- 3
- 4
- 5
- 6
- 7













